United States
Environmental Protection Agency
EPA-AA-RSPD-IM-96-2
July 1996
Air
Acceleration Simulation Mode Test
Procedures, Emission Standards, Quality
Control Requirements, and Equipment
Specifications
Technical Guidance
-------
Table of Contents
Page
§85.1 Test Standards and Calculations 1
(a) Emissions Standards 1
(b) Test Score Calculation 7
§85.2 Test Procedures 9
(a) General Requirements. 9
(b) Vehicle Pre-inspection and Preparation. 9
(c) Equipment Preparation and Settings. 10
(d) Test Procedure. 12
(e) Second Chance Tests. 15
§85.3 Test Equipment Specifications 16
(a) Dynamometer Specifications. 16
(b) Emission Sampling System. 19
(c) Analytical Instruments. 21
(d) Automated Test Process Software and Displays. 24
§85.4 Quality Control Requirements 26
(a) General Requirements 26
(b) Dynamometer 26
(c) Emission Sampling System. 30
(d) Analytic Instruments. 31
§85.5 Test Record Information 38
(a) General Information. 38
(b) Ambient Test Conditions. 38
(c) ASM Mode or Modes. 38
(d) Diagnostic/Quality Assurance Information. 38
-------
§85.1 §85.1
§85.1 Test Standards and Calculations
(a) Emissions Standards
(1) Start-up ASM Standards. Start-up standards should be used during the first cycle of
the program. The exhaust emissions standards for the following model years and
vehicle types are cross-referenced by the number in the column in §85.1(a)(3), as
noted in the column headings:
(i)
Light Duty Vehicles.
Model Years
Hydrocarbons
Table §85.1 (a)(3)(i)
Carbon Monoxide
Table §85.1 (a)(3)(ii)
Oxides of Nitrogen
Table §85.1 (a)(3)(iii)
1 994+ Tier 1
1991-1995
1983-1990
1981-1982
1980
1977-1979
1975-1976
1973-1974
1968-1972
1
2
4
4
4
11
11
13
13
21
22
23
26
26
30
30
34
34
41
42
43
43
48
48
50
50
51
(ii) High-Altitude Light Duty Vehicles.
Model Years
1983-1984
1982
Hydrocarbons
Table §85.1 (a)(3)(i)
4
4
Carbon Monoxide
Table §85.1 (a)(3)(ii)
26
29
Oxides of Nitrogen
Table §85.1 (a)(3)(iii)
43
43
(iii) Light Duty Trucks 1 (less than 6000 pounds GVWRY
Model Years
Hydrocarbons
Table §85.1 (a)(3)(i)
Carbon Monoxide
Table §85.1 (a)(3)(ii)
Oxides of Nitrogen
Table §85.1 (a)(3)(iii)
1994+ Tier 1 <3750 LVW
1994+ Tier 1>3750LVW
1991-1995
1988-1990
1984-1987
1979-1983
1975-1978
1973-1974
1968-1972
1
2
5
7
7
11
12
13
13
21
22
26
29
29
31
32
34
34
41
42
43
44
49
49
50
50
51
(iv) High-Altitude Light Duty Trucks 1 (less than 6000 pounds GVWRY
Model Years
Hydrocarbons
Table §85.1 (a)(3)(i)
Carbon Monoxide
Table §85.1 (a)(3)(ii)
Oxides of Nitrogen
Table §85.1 (a)(3)(iii)
Page 1
7/2/96
Test Standards and Calculations
-------
§85.1
§85.1
1991 +
1988-1990
1984-1987
1982-1983
6
9
9
12
28
30
30
43
44
49
49
(v) Light Duty Trucks 2 (greater than 6000 pounds GVWRY
Model Years Hydrocarbons Carbon Monoxide Oxides of Nitrogen
Table §85.1 (a)(3)(i) Table §85.1 (a)(3)(ii) Table §85.1 (a)(3)(iii)
1994+Tier 1<5750LVW 2
1994+ Tier 1 >5750 LVW 5
1991-1995 5
1988-1990 7
1984-1987 7
1979-1983 11
1975-1978 12
1973-1974 13
1968-1972 13
22
26
26
29
29
31
32
34
34
42
45
46
47
49
49
50
50
51
(vi) High-Altitude Light Duty Trucks 2 (greater than 6000 pounds GVWRY
Model Years
1991 +
1988-1990
1984-1987
1982-1983
Hydrocarbons
Table §85.1 (a)(3)(i)
9
9
12
Carbon Monoxide Oxides of Nitrogen
Table §85.1 (a)(3)(ii) Table §85.1 (a)(3)(iii)
28
30
30
33
46
47
49
49
(2) Final ASM Standards. The following exhaust emissions standards are designed to
achieve the emission reduction credits issued by EPA. They should only be used
after at least one cycle of operation using the start-up standards in §85. l(a)(l). The
exhaust emissions standards for the following model years and vehicle types are
cross-referenced by the number in the column in §85.1(a)(3), as noted in the column
headings:
(i) Light Duty Vehicles.
Model Years
1994+Tier 1
1983-1995
1981-1982
1980
1977-1979
1975-1976
1973-1974
1968-1972
Hydrocarbons
Table §85.1 (a)(3)(i)
1
1
1
1
6
6
10
10
Carbon Monoxide
Table §85.1 (a)(3)(ii)
21
21
23
23
27
27
32
32
Oxides of Nitrogen
Table §85.1 (a)(3)(iii)
41
41
41
45
45
48
48
49
Page 2
7/2/96
Test Standards and Calculations
-------
§85.1 §85.1
(ii) High-Altitude Light Duty Vehicles.
Model Years Hydrocarbons Carbon Monoxide Oxides of Nitrogen
Table §85.1 (a)(3)(i) Table §85.1 (a)(3)(ii) Table §85.1 (a)(3)(iii)
1983-1984 2 23 41
1982 2 23 41
(iii) Light Duty Trucks 1 (less than 6000 pounds GVWRY
Model Years Hydrocarbons Carbon Monoxide Oxides of Nitrogen
Table §85.1 (a)(3)(i) Table §85.1 (a)(3)(ii) Table §85.1 (a)(3)(iii)
1994+Tier 1 1 21 41
1988-1995 3 24 42
1984-1987 3 24 46
1979-1983 8 28 46
1975-1978 9 29 48
1973-1974 10 32 48
1968-1972 10 32 49
(iv) High-Altitude Light Duty Trucks 1 (less than 6000 pounds GVWRY
Model Years Hydrocarbons Carbon Monoxide Oxides of Nitrogen
Table §85.1 (a)(3)(i) Table §85.1 (a)(3)(ii) Table §85.1 (a)(3)(iii)
1988+ 4 26 42
1984-1987 4 26 46
1982-1983 9 30 46
(v) Light Duty Trucks 2 (greater than 6000 pounds GVWRY
Model Years Hydrocarbons Carbon Monoxide Oxides of Nitrogen
Table §85.1 (a)(3)(i) Table §85.1 (a)(3)(ii) Table §85.1 (a)(3)(iii)
1994+Tier 1 1 21 41
1988-1995 3 24 44
1984-1987 3 24 46
1979-1983 8 28 46
1975-1978 9 29 48
1973-1974 10 32 48
1968-1972 10 32 49
(vi) High-Altitude Light Duty Trucks 2 (greater than 6000 pounds GVWRY
Model Years Hydrocarbons Carbon Monoxide Oxides of Nitrogen
Table §85.1 (a)(3)(i) Table §85.1 (a)(3)(ii) Table §85.1 (a)(3)(iii)
1988+ 4 26 44
1984-1987 4 26 46
1982-1983 9 30 46
Page 3 7/2/96 Test Standards and Calculations
-------
§85.1
§85.1
(3) ASM 2525 and 5015 Concentration Tables
(i) ASM2525 and ASM5015 Hydrocarbon (ppm C6) Table
Column #
ETW
1750
1875
2000
2125
2250
2375
2500
2625
2750
2875
3000
3125
3250
3375
3500
3625
3750
3875
4000
4125
4250
4375
4500
4625
4750
4875
5000
5125
5250
5375
5500
5625
5750
5875
6000
6125
6250
6375
6500
6625
6750
6875
7000
7125
7250
7375
7500
i
5015
142
134
127
121
115
109
105
100
96
92
89
86
83
81
78
76
74
72
71
69
67
66
65
63
62
61
60
58
57
56
55
54
53
52
51
50
50
49
48
48
47
47
47
47
47
47
47
1
2525
136
129
123
116
111
106
101
97
93
89
86
83
80
78
76
74
72
70
68
67
65
64
63
61
60
59
58
57
56
55
54
53
52
51
50
49
48
48
47
46
46
46
46
46
46
46
46
2
5015
224
212
201
191
182
173
166
159
152
146
141
136
132
128
124
120
117
114
112
109
107
104
102
100
98
96
94
93
91
89
87
86
84
83
81
80
79
77
76
76
75
75
74
74
74
74
74
2
2525
216
205
194
184
175
167
160
153
147
141
136
132
127
123
120
117
114
111
108
106
103
101
99
97
95
93
92
90
88
86
85
83
82
80
79
78
76
75
74
74
73
73
72
72
72
72
72
3
5015
257
243
230
219
208
198
189
181
173
167
160
155
149
145
140
136
133
129
126
123
120
118
115
113
110
108
106
104
102
100
98
96
94
92
90
89
87
86
85
84
83
83
83
82
82
82
82
3
2525
249
236
223
212
201
192
183
175
168
161
155
150
145
140
136
132
129
125
122
119
117
114
112
109
107
105
103
101
99
97
95
93
91
90
88
86
85
84
83
82
81
81
80
80
80
80
80
4
5015
291
275
260
246
234
223
212
203
194
187
180
173
167
162
157
152
148
144
140
137
134
131
128
125
122
120
117
115
112
110
108
106
104
102
100
98
96
95
93
92
91
91
91
90
90
90
90
4
2525
282
266
252
239
227
216
206
197
189
181
174
168
162
157
152
148
144
140
137
133
130
127
124
122
119
117
114
112
110
107
105
103
101
99
97
95
94
92
91
90
89
89
88
88
88
88
88
5
5015
324
306
289
274
260
247
236
225
216
207
199
191
185
179
173
168
163
159
155
151
147
144
141
137
134
132
129
126
123
121
118
116
113
111
109
107
105
103
102
101
100
99
99
98
98
98
98
5
2525
315
297
281
267
253
241
230
219
210
201
194
186
180
174
169
164
159
155
151
147
143
140
137
134
131
128
126
123
120
118
115
113
111
108
106
104
102
101
99
98
97
97
96
96
96
96
96
6
5015
374
353
333
316
299
284
271
259
247
237
228
219
211
204
198
192
186
181
176
172
167
164
160
156
153
149
146
143
140
137
134
131
128
125
123
120
118
116
114
113
112
111
111
111
111
111
111
6
2525
364
344
325
308
292
277
264
252
241
231
222
214
206
199
193
187
182
177
172
168
164
160
156
152
149
146
143
139
136
133
130
128
125
122
120
118
115
113
112
110
109
109
108
108
108
108
108
7
5015
390
368
348
329
312
297
283
270
258
247
237
228
220
213
206
200
194
188
183
179
174
170
166
162
159
155
152
148
145
142
139
136
133
130
127
125
123
120
119
117
116
115
115
115
115
115
115
7
2525
381
359
339
321
305
290
276
263
252
241
232
223
215
208
201
195
189
184
179
175
170
166
162
159
155
152
148
145
142
139
136
133
130
127
124
122
120
118
116
114
113
113
112
112
112
112
112
8
5015
407
384
363
343
325
309
294
281
269
257
247
238
229
221
214
207
201
196
191
186
181
177
172
169
165
161
157
154
150
147
144
141
138
135
132
129
127
125
123
121
120
119
119
119
119
119
119
8
2525
397
375
354
335
318
302
288
274
262
251
241
232
224
216
209
203
197
191
186
181
177
173
169
165
161
157
154
150
147
144
141
138
135
132
129
126
124
122
120
119
117
117
116
116
116
116
116
9
5015
457
431
407
385
365
346
329
314
300
287
276
265
256
247
239
231
224
218
212
206
201
196
192
187
183
179
175
171
167
163
159
156
152
149
146
143
140
138
136
134
132
132
131
131
131
131
131
9
2525
447
421
398
376
357
339
322
307
294
281
270
260
250
241
234
226
220
213
208
202
197
192
188
183
179
175
171
167
163
159
156
152
149
146
143
140
137
135
133
131
129
129
128
128
128
128
128
10
5015
706
665
627
592
560
531
505
481
459
439
420
404
388
374
362
350
339
329
320
311
303
295
287
280
273
267
260
254
248
242
236
231
225
220
215
210
206
202
199
196
194
193
192
192
192
192
192
10
2525
694
653
616
582
551
522
496
472
451
431
413
397
382
368
355
344
333
323
314
305
297
290
282
275
269
262
256
250
244
238
232
226
221
216
211
206
202
198
195
192
190
189
188
188
188
188
188
11
5015
774
729
688
650
615
583
554
528
503
481
461
443
426
411
397
384
372
361
351
341
332
323
315
308
300
293
286
279
272
266
259
253
247
241
236
231
226
222
218
215
213
211
211
211
211
211
211
11
2525
761
717
676
638
604
573
544
518
495
473
453
435
419
404
390
377
365
355
345
335
326
318
310
302
295
288
281
274
267
261
255
248
243
237
232
227
222
218
214
211
209
207
207
206
206
206
206
12
5015
843
794
749
707
669
635
603
574
548
524
502
482
464
447
432
418
405
393
382
371
361
352
343
335
327
319
311
304
296
289
282
276
269
263
257
251
246
242
238
234
232
230
229
229
229
229
229
12
2525
828
780
736
695
658
624
593
564
539
515
493
474
456
440
424
411
398
386
375
365
355
346
337
329
321
313
305
298
291
284
277
271
264
258
252
247
242
237
233
230
227
225
225
225
225
225
225
13
5015
1118
1052
992
938
887
841
800
761
726
695
666
639
615
593
573
554
537
521
506
492
479
467
455
444
433
423
412
402
393
383
374
365
357
348
341
333
326
320
315
310
307
305
304
304
304
304
304
13
2525
1098
1034
975
921
872
827
786
748
714
683
654
628
604
583
563
544
527
512
497
484
471
459
447
436
425
415
405
395
386
376
367
359
350
342
334
327
320
314
309
304
301
299
298
298
298
298
298
Page 4
7/2/96
Test Standards and Calculations
-------
§85.1
§85.1
(ii) ASM2525 and ASM5015 Carbon Monoxide (%CO) Table
Column #
ETW
1750
1875
2000
2125
2250
2375
2500
2625
2750
2875
3000
3125
3250
3375
3500
3625
3750
3875
4000
4125
/lo ^n
4zjU
4375
4500
4625
4750
4875
5000
5125
5250
5375
5500
5625
5750
5875
6000
6125
6250
6375
6500
6625
6750
6875
7000
7125
7250
7375
7500
21
5015
0.80
0.75
0.71
0.68
0.64
0.61
0.59
0.56
0.54
0.52
0.50
0.48
0.46
0.45
0.44
0.42
0.41
0.40
0.39
0.38
0.37
0.36
0.36
0.35
0.34
0.34
0.33
0.32
0.32
0.31
0.30
0.30
0.29
0.29
0.28
0.28
0.27
0.27
0.26
0.26
0.26
0.26
0.25
0.25
0.25
0.25
0.25
21
2525
0.77
0.73
0.69
0.66
0.62
0.59
0.57
0.54
0.52
0.50
0.48
0.46
0.45
0.43
0.42
0.41
0.40
0.39
0.38
0.37
0.36
0.35
0.35
0.34
0.33
0.33
0.32
0.31
0.31
0.30
0.30
0.29
0.29
0.28
0.28
0.27
0.27
0.26
0.26
0.26
0.26
0.25
0.25
0.25
0.25
0.25
0.25
22
5015
1.26
1.19
1.13
1.07
1.02
0.97
0.93
0.89
0.85
0.82
0.79
0.76
0.73
0.71
0.69
0.67
0.65
0.63
0.62
0.60
0.59
0.58
0.57
0.55
0.54
0.53
0.52
0.51
0.50
0.49
0.48
0.47
0.46
0.45
0.44
0.44
0.43
0.42
0.42
0.41
0.41
0.40
0.40
0.40
0.40
0.40
0.40
22
2525
1.22
1.16
1.09
1.04
0.99
0.94
0.90
0.86
0.82
0.79
0.76
0.73
0.71
0.69
0.67
0.65
0.63
0.61
0.60
0.58
0.57
0.56
0.55
0.54
0.53
0.52
0.51
0.50
0.49
0.48
0.47
0.46
0.45
0.44
0.44
0.43
0.42
0.42
0.41
0.41
0.41
0.40
0.40
0.40
0.40
0.40
0.40
23
5015
1.64
1.55
1.47
1.39
1.32
1.26
1.20
1.15
1.10
1.05
1.01
0.98
0.94
0.91
0.88
0.86
0.83
0.81
0.79
0.77
0.75
0.74
0.72
0.70
0.69
0.67
0.66
0.65
0.63
0.62
0.61
0.59
0.58
0.57
0.56
0.55
0.54
0.53
0.52
0.52
0.51
0.51
0.51
0.51
0.50
0.50
0.50
23
2525
1.83
1.72
1.63
1.54
1.47
1.39
1.33
1.27
1.21
1.16
1.12
1.08
1.04
1.00
0.97
0.94
0.92
0.89
0.87
0.85
0.83
0.81
0.79
0.77
0.76
0.74
0.73
0.71
0.70
0.68
0.67
0.65
0.64
0.63
0.62
0.61
0.60
0.59
0.58
0.57
0.57
0.56
0.56
0.56
0.56
0.56
0.56
24
5015
2.02
1.91
1.81
1.71
1.62
1.54
1.47
1.41
1.34
1.29
1.24
1.19
1.15
1.11
1.08
1.05
1.02
0.99
0.96
0.94
0.92
0.89
0.87
0.85
0.84
0.82
0.80
0.78
0.77
0.75
0.73
0.72
0.70
0.69
0.67
0.66
0.65
0.64
0.63
0.62
0.61
0.61
0.61
0.61
0.61
0.61
0.61
24
2525
2.43
2.29
2.17
2.05
1.94
1.85
1.76
1.68
1.60
1.54
1.48
1.42
1.37
1.32
1.28
1.24
1.20
1.17
1.14
1.11
1.08
1.06
1.03
1.01
0.99
0.97
0.95
0.92
0.90
0.89
0.87
0.85
0.83
0.81
0.80
0.78
0.77
0.76
0.74
0.73
0.73
0.72
0.72
0.72
0.72
0.72
0.72
25
5015
2.21
2.09
1.97
1.87
1.77
1.69
1.61
1.53
1.47
1.41
1.35
1.30
1.26
1.21
1.17
1.14
1.11
1.08
1.05
1.02
1.00
0.97
0.95
0.93
0.91
0.89
0.87
0.85
0.83
0.81
0.80
0.78
0.76
0.75
0.73
0.72
0.71
0.69
0.68
0.67
0.67
0.66
0.66
0.66
0.66
0.66
0.66
25
2525
2.73
2.58
2.43
2.30
2.18
2.07
1.97
1.88
1.80
1.72
1.66
1.59
1.53
1.48
1.43
1.39
1.35
1.31
1.28
1.24
1.21
1.18
1.16
1.13
1.10
1.08
1.05
1.03
1.01
0.99
0.97
0.94
0.92
0.91
0.89
0.87
0.85
0.84
0.83
0.82
0.81
0.80
0.80
0.80
0.80
0.80
0.80
26
5015
2.78
2.63
2.48
2.35
2.23
2.12
2.02
1.92
1.84
1.76
1.69
1.63
1.57
1.52
1.47
1.42
1.38
1.34
1.31
1.27
1.24
1.21
1.18
1.15
1.13
1.10
1.08
1.05
1.03
1.01
0.99
0.97
0.94
0.92
0.91
0.89
0.87
0.86
0.84
0.83
0.82
0.82
0.82
0.81
0.81
0.81
0.81
26
2525
3.64
3.43
3.24
3.06
2.90
2.76
2.62
2.50
2.39
2.29
2.19
2.11
2.03
1.96
1.89
1.84
1.78
1.73
1.68
1.64
1.60
1.56
1.52
1.48
1.45
1.42
1.38
1.35
1.32
1.29
1.26
1.24
1.21
1.18
1.16
1.13
1.11
1.09
1.08
1.06
1.05
1.04
1.04
1.04
1.04
1.04
1.04
27
5015
2.97
2.81
2.65
2.51
2.38
2.26
2.15
2.05
1.96
1.88
1.80
1.74
1.67
1.62
1.56
1.52
1.47
1.43
1.39
1.36
1.32
1.29
1.26
1.23
1.20
1.17
1.15
1.12
1.10
1.07
1.05
1.03
1.01
0.98
0.96
0.94
0.93
0.91
0.90
0.88
0.88
0.87
0.87
0.87
0.86
0.86
0.86
27
2525
3.94
3.71
3.51
3.32
3.14
2.98
2.84
2.70
2.58
2.47
2.37
2.28
2.20
2.12
2.05
1.98
1.92
1.87
1.82
1.77
1.72
1.68
1.64
1.60
1.57
1.53
1.49
1.46
1.43
1.39
1.36
1.33
1.30
1.27
1.25
1.22
1.20
1.18
1.16
1.14
1.13
1.12
1.12
1.12
1.12
1.12
1.12
28
5015
3.16
2.98
2.82
2.67
2.53
2.40
2.29
2.18
2.09
2.00
1.92
1.84
1.78
1.72
1.66
1.61
1.56
1.52
1.48
1.44
1.40
1.37
1.34
1.30
1.28
1.25
1.22
1.19
1.16
1.14
1.11
1.09
1.07
1.04
1.02
1.00
0.98
0.96
0.95
0.94
0.93
0.92
0.92
0.92
0.92
0.92
0.92
28
2525
4.24
4.00
3.77
3.57
3.38
3.21
3.05
2.91
2.78
2.66
2.55
2.45
2.36
2.28
2.20
2.13
2.07
2.01
1.95
1.90
1.85
1.81
1.76
1.72
1.68
1.64
1.60
1.57
1.53
1.50
1.46
1.43
1.40
1.37
1.34
1.31
1.28
1.26
1.24
1.23
1.21
1.20
1.20
1.20
1.20
1.20
1.20
29
5015
3.54
3.34
3.16
2.99
2.83
2.69
2.56
2.44
2.33
2.23
2.14
2.06
1.99
1.92
1.86
1.80
1.74
1.69
1.65
1.61
1.56
1.53
1.49
1.46
1.42
1.39
1.36
1.33
1.30
1.27
1.24
1.21
1.19
1.16
1.14
1.11
1.09
1.07
1.06
1.04
1.03
1.02
1.02
1.02
1.02
1.02
1.02
29
2525
4.85
4.57
4.31
4.08
3.86
3.66
3.48
3.32
3.17
3.03
2.91
2.79
2.69
2.60
2.51
2.43
2.36
2.29
2.22
2.16
2.11
2.06
2.01
1.96
1.91
1.87
1.82
1.78
1.74
1.70
1.66
1.62
1.59
1.55
1.52
1.49
1.46
1.43
1.41
1.39
1.37
1.36
1.36
1.36
1.36
1.36
1.36
30
5015
3.92
3.70
3.49
3.31
3.13
2.98
2.83
2.70
2.58
2.47
2.37
2.28
2.20
2.12
2.05
1.99
1.93
1.87
1.82
1.77
1.73
1.68
1.64
1.61
1.57
1.53
1.50
1.46
1.43
1.40
1.37
1.34
1.31
1.28
1.25
1.23
1.20
1.18
1.16
1.15
1.14
1.13
1.12
1.12
1.12
1.12
1.12
30
2525
5.45
5.14
4.85
4.58
4.34
4.12
3.91
3.73
3.56
3.41
3.27
3.14
3.02
2.91
2.82
2.73
2.64
2.57
2.49
2.43
2.36
2.31
2.25
2.19
2.14
2.09
2.04
2.00
1.95
1.90
1.86
1.82
1.78
1.74
1.70
1.66
1.63
1.60
1.57
1.55
1.54
1.52
1.52
1.52
1.52
1.52
1.52
31
5015
4.31
4.06
3.83
3.63
3.44
3.26
3.10
2.96
2.83
2.71
2.60
2.50
2.40
2.32
2.24
2.17
2.11
2.05
1.99
1.94
1.89
1.84
1.80
1.76
1.72
1.68
1.64
1.60
1.56
1.53
1.49
1.46
1.43
1.40
1.37
1.34
1.31
1.29
1.27
1.25
1.24
1.23
1.23
1.22
1.22
1.22
1.22
31
2525
6.06
5.70
5.38
5.09
4.82
4.57
4.35
4.14
3.95
3.78
3.62
3.48
3.35
3.23
3.12
3.02
2.93
2.85
2.77
2.69
2.55
2.49
2.43
2.37
2.32
2.26
2.21
2.16
2.11
2.06
2.01
1.96
1.92
1.88
1.84
1.80
1.77
1.74
1.72
1.70
1.68
1.68
1.68
1.68
1.68
1.68
32
5015
5.07
4.78
4.51
4.26
4.04
3.83
3.65
3.48
3.32
3.18
3.05
2.93
2.82
2.72
2.63
2.55
2.47
2.40
2.33
2.27
2.16
2.11
2.06
2.01
1.96
1.92
1.87
1.83
1.79
1.75
1.71
1.67
1.63
1.60
1.57
1.54
1.51
1.48
1.46
1.45
1.44
1.43
1.43
1.43
1.43
1.43
32
2525
7.26
6.84
6.45
6.10
5.78
5.48
5.21
4.96
4.73
4.53
4.34
4.17
4.01
3.87
3.74
3.62
3.51
3.40
3.31
3.22
3.05
2.98
2.90
2.83
2.77
2.70
2.64
2.58
2.51
2.46
2.40
2.34
2.29
2.24
2.19
2.15
2.11
2.07
2.04
2.02
2.00
2.00
2.00
2.00
2.00
2.00
33
5015
5.26
4.96
4.68
4.43
4.20
3.98
3.79
3.61
3.45
3.30
3.17
3.04
2.93
2.83
2.73
2.65
2.57
2.49
2.43
2.36
2.24
2.19
2.14
2.09
2.04
1.99
1.95
1.90
1.86
1.82
1.77
1.74
1.70
1.66
1.63
1.60
1.57
1.54
1.52
1.50
1.49
1.49
1.49
1.49
1.49
1.49
33
2525
7.44
7.05
6.68
6.34
6.00
5.69
5.41
5.15
4.92
4.70
4.51
4.33
4.17
4.02
3.88
3.76
3.64
3.54
3.44
3.34
3.17
3.09
3.02
2.95
2.87
2.81
2.74
2.68
2.61
2.55
2.49
2.43
2.38
2.33
2.28
2.23
2.19
2.15
2.12
2.10
2.08
2.08
2.08
2.08
2.08
2.08
34
5015
8.02
7.56
7.14
6.75
6.40
6.07
5.78
5.51
5.26
5.03
4.83
4.64
4.47
4.31
4.17
4.04
3.91
3.80
3.70
3.60
3.51
3.42
3.34
3.26
3.18
3.11
3.03
2.97
2.90
2.83
2.77
2.70
2.64
2.59
2.53
2.48
2.43
2.39
2.35
2.32
2.29
2.28
2.27
2.27
2.27
2.27
2.27
34
2525
9.90
9.90
9.90
9.66
9.14
8.67
8.25
7.85
7.50
7.17
6.87
6.60
6.35
6.13
5.92
5.73
5.55
5.39
5.24
5.09
4.96
4.83
4.71
4.60
4.49
4.38
4.28
4.18
4.08
3.98
3.89
3.80
3.71
3.62
3.54
3.47
3.40
3.34
3.28
3.23
3.20
3.17
3.17
3.17
3.17
3.17
3.17
Page 5
7/2/96
Test Standards and Calculations
-------
§85.1
§85.1
(iii) ASM2525 and ASM5015 Nitric Oxide (% NO) Table
Column #
ETW
1750
1875
2000
2125
2250
2375
2500
2625
2750
2875
3000
3125
3250
3375
3500
3625
3750
3875
4000
4125
4250
4375
4500
4625
4750
4875
5000
5125
5250
5375
5500
5625
5750
5875
6000
6125
6250
6375
6500
6625
6750
6875
7000
7125
7250
7375
7500
41
5015
1212
1142
1077
1018
964
915
869
828
791
756
725
696
670
647
625
605
586
569
553
538
524
510
498
486
474
463
452
441
431
420
410
401
391
383
374
366
359
352
346
341
338
335
335
335
335
335
335
41
2525
1095
1031
973
920
871
827
786
749
715
684
656
630
607
585
566
547
531
515
501
487
475
463
451
440
430
420
410
400
391
382
373
364
356
348
340
333
326
320
315
311
307
305
305
305
305
305
305
42
5015
1819
1713
1616
1527
1446
1372
1304
1242
1186
1134
1088
1045
1006
970
937
907
879
853
829
807
786
766
747
728
711
694
677
661
646
631
616
601
587
574
561
549
538
528
519
512
507
503
502
502
502
502
502
42
2525
1642
1547
1460
1380
1307
1240
1179
1123
1072
1026
984
945
910
878
848
821
796
773
751
731
712
694
677
661
645
630
615
600
586
573
559
546
534
522
510
499
489
480
473
466
461
458
457
457
457
457
457
43
5015
2272
2181
2058
1944
1839
1744
1657
1577
1504
1438
1378
1323
1273
1227
1184
1146
1110
1077
1046
1017
990
964
939
916
893
872
850
830
810
790
771
752
734
717
701
685
671
658
647
638
631
626
624
625
625
625
625
43
2525
2114
1991
1877
1774
1678
1592
1512
1440
1374
1313
1258
1208
1163
1121
1082
1047
1014
984
956
930
905
882
859
838
818
798
778
760
741
723
706
689
673
657
642
628
615
604
593
585
578
574
573
573
573
573
573
44
5015
2725
2649
2499
2360
2232
2115
2009
1912
1823
1742
1668
1601
1539
1483
1432
1384
1340
1300
1262
1227
1194
1162
1132
1104
1076
1049
1023
998
974
950
926
904
882
860
840
822
804
788
775
763
755
749
747
747
747
747
747
44
2525
2587
2435
2295
2167
2050
1943
1845
1756
1675
1601
1533
1471
1415
1363
1316
1273
1233
1195
1161
1128
1098
1069
1042
1015
990
966
942
919
896
874
853
832
812
793
774
757
741
727
714
704
696
691
689
689
689
689
689
45
5015
3178
3117
2941
2776
2625
2487
2361
2246
2142
2046
1959
1879
1806
1740
1679
1623
1571
1523
1479
1437
1398
1360
1325
1291
1259
1227
1196
1167
1138
1109
1082
1055
1029
1004
980
958
937
919
902
889
879
872
870
870
870
870
870
45
2525
3060
2879
2713
2561
2422
2295
2179
2073
1976
1888
1808
1734
1667
1606
1550
1498
1451
1407
1365
1327
1291
1257
1224
1193
1163
1134
1106
1078
1051
1025
1000
975
951
928
906
886
867
850
835
823
813
807
805
805
805
805
805
46
5015
3631
3586
3383
3192
3018
2859
2714
2581
2460
2350
2249
2157
2073
1997
1926
1862
1802
1747
1695
1647
1602
1559
1518
1479
1441
1405
1369
1335
1301
1269
1237
1206
1176
1147
1120
1094
1070
1049
1030
1014
1003
995
992
992
992
992
992
46
2525
3532
3323
3131
2955
2794
2646
2512
2389
2277
2175
2082
1997
1920
1849
1784
1724
1669
1618
1570
1526
1484
1444
1406
1370
1336
1302
1269
1237
1206
1176
1147
1118
1090
1064
1039
1015
993
973
956
941
931
924
921
921
921
921
921
47
5015
4084
4054
3824
3609
3411
3231
3066
2916
2779
2654
2539
2435
2340
2253
2174
2100
2033
1970
1912
1857
1806
1757
1711
1666
1624
1583
1542
1503
1465
1428
1392
1357
1323
1290
1259
1230
1203
1179
1158
1140
1127
1118
1115
1115
1115
1115
1115
47
2525
4005
3767
3548
3348
3165
2998
2845
2706
2579
2463
2357
2260
2172
2092
2018
1950
1887
1829
1775
1724
1677
1632
1589
1548
1508
1470
1433
1397
1362
1327
1294
1261
1230
1199
1171
1144
1119
1096
1077
1060
1048
1040
1037
1037
1037
1037
1037
48
5015
4990
4990
4707
4441
4197
3974
3771
3585
3416
3261
3120
2992
2874
2767
2668
2578
2494
2417
2345
2277
2214
2154
2096
2042
1989
1938
1889
1840
1793
1747
1703
1659
1617
1577
1539
1503
1469
1439
1413
1391
1374
1364
1360
1360
1360
1360
1360
48
2525
4950
4655
4384
4136
3909
3701
3512
3339
3181
3037
2906
2787
2677
2577
2486
2401
2323
2251
2184
2122
2063
2007
1953
1903
1854
1806
1760
1715
1672
1629
1587
1547
1508
1471
1435
1401
1371
1343
1318
1298
1283
1273
1269
1269
1269
1269
1269
49
5015
4990
4990
4778
4578
4395
4228
4076
3936
3809
3669
3510
3366
3234
3113
3002
2900
2806
2719
2638
2562
2490
2423
2359
2297
2238
2180
2125
2070
2017
1966
1916
1867
1820
1774
1731
1690
1653
1619
1590
1565
1546
1534
1530
1531
1531
1531
1531
49
2525
4960
4738
4535
4349
4179
4024
3881
3752
3579
3417
3270
3135
3012
2899
2796
2701
2614
2533
2457
2387
2320
2258
2198
2140
2085
2032
1980
1930
1881
1833
1786
1740
1697
1654
1614
1577
1542
1510
1483
1460
1443
1432
1428
1428
1428
1428
1428
50
5015
4990
4990
4919
4853
4792
4736
4685
4639
4596
4484
4290
4114
3952
3804
3669
3544
3429
3323
3224
3131
3044
2961
2883
2807
2735
2665
2597
2530
2466
2403
2341
2282
2224
2168
2116
2066
2020
1979
1943
1913
1890
1875
1870
1874
1874
1874
1874
50
2525
4980
4906
4838
4776
4720
4668
4620
4577
4374
4176
3996
3832
3681
3544
3418
3302
3195
3096
3003
2917
2836
2759
2686
2616
2549
2483
2420
2359
2298
2240
2183
2127
2074
2022
1973
1927
1884
1846
1813
1785
1764
1750
1745
1745
1745
1745
1745
51
5015
4990
4990
4990
4990
4990
4990
4990
4990
4990
4892
4680
4488
4311
4150
4002
3867
3741
3625
3517
3416
3321
3230
3145
3063
2983
2907
2833
2760
2690
2621
2554
2489
2426
2366
2308
2254
2204
2159
2119
2087
2062
2046
2040
2045
2045
2045
2045
51
2525
4990
4990
4990
4990
4990
4990
4990
4990
4772
4556
4359
4180
4016
3866
3728
3602
3485
3377
3276
3182
3094
3010
2930
2854
2780
2709
2640
2573
2507
2443
2381
2321
2262
2206
2152
2102
2056
2014
1977
1947
1924
1909
1904
1904
1904
1904
1904
Page 6
7/2/96
Test Standards and Calculations
-------
§85.1 §85.1
(b) Test Score Calculation
(1) Exhaust Gas Measurement Calculation.
(i) Measurement Start. The analysis and recording of exhaust gas concentrations
shall begin 15 seconds after the applicable test mode begins, or sooner if the
system response time (to 100%) is less than 15 seconds. The analysis and
recording of exhaust gas concentrations shall not begin sooner than the time
period equivalent to the response time of the slowest transducer.
(ii) Sample Rate. Exhaust gas concentrations shall be analyzed at a minimum
rate of once per second.
(iii) Emission Measurement Calculations. Partial stream (concentration)
emissions shall be calculated based on a running 10 second average. The
values used for HC(j), CO(j), and NO(j) are the raw (uncorrected) tailpipe
concentrations.
JHCG)*DCFG)
(A) AvgHC = ^ - ^ -
JCOG)*DCFG)
(B) AvgCO = ^ - jo -
JNOG)*DCFG)
(C) AvgNO = ^ - ^ -
(iv) Dilution Correction Factor. The analyzer software shall multiply the raw
emissions values by the Dilution Correction Factor (DCF) during any valid
ASM emissions test. The DCF accounts for exhaust sample dilution (either
intentional or unintentional) during an emissions test. The analyzer software
shall calculate the DCF using the following procedure, and shall select the
appropriate vehicle fuel formula. If the calculated DCF exceeds 3.0 then a
default value of 3.0 shall be used.
__ [CO2]measured _
[CO2]measured + [CO]measured
Where [CO2]measured and [CO]measured are the instantaneous
ASM emissions test readings.
(B) Calculate [CO2]adjusted using the following formulas.
(1) For Gasoline:
Page 7 7/2/96 Test Standards and Calculations
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§85.1 §85.1
(2) For Methanol or Ethanol:
[C02]adjusted = [4.73*.88x] *100
(3) For Compressed Natural Gas (CNG):
(4) For Liquid Propane Gas (LPG):
[C02]adjusted = [5.39*.88x] *100
(C) Calculate the DCF using the following formula:
[CO2]adjusted
[CO2]measured
(v) NO Humidity Correction Factor. The NO measurement shall be adjusted
based on relative humidity using a correction factor Kh, calculated as follows:
(A) Kh= 1 - 0.0047(H-75)
(B) H = Absolute humidity in grains of water per pound of dry air.
(43.478)Ra*Pd
PB-(Pd*Ra/100)
(C) Ra = Relative humidity of the ambient air, percent.
(D) Pd = Saturated vapor pressure, mm Hg at the ambient dry bulb
temperature. If the temperature is above 86_F, then it
shall be used in lieu of the higher temperature, until EPA
supplies final correction factors.
(E) PB = Barometric pressure, mm Hg.
(2) Pass/Fail Determination. A pass or fail determination shall be made for each
applicable test mode based on a comparison of the applicable test standards and the
measured value for HC, CO, and NO as described in §85.1(b)(l)(iii). A vehicle shall
pass the test mode if the emission values for HC, CO, and NO are simultaneously
below or equal to the applicable short test standards for all three pollutants. A
vehicle shall fail the test mode if the values for HC, CO, or NO, or any combination
of the three, are above the applicable standards at the expiration of the test time.
Page 8 7/2/96 Test Standards and Calculations
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§85.2 §85.2
§85.2 Test Procedures
(a) General Requirements.
(1) Vehicle Characterization. The following information shall be determined for the
vehicle being tested and used to automatically select the dynamometer power
absorption settings:
(i) Vehicle type: LDGV, LDGT1, LDGT2, HDGT, and others as needed
(ii) Chassis model year
(iii) Make
(iv) Model
(v) Number of cylinders
(vi) Cubic inch or liters displacement of the engine
(vii) Transmission type
(viii) Equivalent Test Weight.
(2) Ambient Conditions. The ambient temperature, absolute humidity, and barometric
pressure shall be recorded continuously during the test cycle or as a single set of
readings up to 4 minutes before the start of the driving cycle.
(3) Restart. If shut off, the vehicle shall be restarted as soon as possible before the test
and shall be running for at least 30 seconds prior to the start of the ASM driving
cycle.
(4) Void Test Conditions. The test shall immediately end and any exhaust gas
measurements shall be voided if the instantaneous measured concentration of CO
plus CO2 falls below six percent or the vehicle's engine stalls at any time during the
test sequence.
(5) Vehicle Brakes. The vehicle's brakes shall not be applied during the test modes. If
the vehicles brakes are applied during testing the mode timer shall be reset to zero (tt
= 0).
(6) Test Termination. The test shall be aborted or terminated upon reaching the overall
maximum test time.
(b) Vehicle Pre-inspection and Preparation.
(1) Accessories. All accessories (air conditioning, heat, defogger, radio, automatic
traction control if switchable, etc.) shall be turned off (if necessary, by the inspector).
(2) Exhaust Leaks. The vehicle shall be inspected for exhaust leaks. Audio assessment
while blocking exhaust flow, or gas measurement of carbon dioxide or other gases
shall be acceptable. Vehicles with leaking exhaust systems shall be rejected from
testing.
Page 9 7/2/96 Test Procedures
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§85.2 §85.2
(3) Fluid Leaks. The vehicle shall be inspected for fluid leaks. Vehicles with leaking
engine oil, transmission fluid, or coolant shall be rejected from testing.
(4) Mechanical Condition. Vehicles with obvious mechanical problems (engine,
transmission, brakes, or exhaust) that either create a safety hazard or could bias test
results shall be rejected from testing.
(5) Operating Temperature. The vehicle shall be at normal operating temperature prior
to the start of the test. The vehicle temperature gauge, if equipped and operating,
shall be checked to assess temperature. Vehicles in overheated condition shall be
rejected from testing.
(6) Tire Condition. Vehicles shall be rejected from testing if tread indicators, tire cords,
bubbles, cuts, or other damage are visible. Vehicles shall be rejected from testing if
they have space-saver spare tires or if they do not have reasonably sized tires on the
drive axle or axles. Vehicles may be rejected if they have different sized tires on the
drive axle or axles. In test-and-repair facilities, drive wheel tires shall be checked
with a gauge for adequate tire pressure. In test-only facilities, drive wheel tires shall
be visually checked for adequate pressure level. Drive wheel tires that appear low
shall be inflated to approximately 30 psi, or to tire side wall pressure, or vehicle
manufacturer's recommendation. Alternatively, vehicles with apparent low tire
pressure may be rejected from testing.
(7) Gear Selection. The vehicle shall be operated during each mode of the test with the
gear selector in drive for automatic transmissions and in second (or third if more
appropriate) for manual transmissions for the loaded modes.
(8) Roll Rotation. The vehicle shall be maneuvered onto the dynamometer with the
drive wheels positioned on the dynamometer rolls. Prior to test initiation, the rolls
shall be rotated until the vehicle laterally stabilizes on the dynamometer. Vehicles
that cannot be stabilized on the dynamometer shall be rejected from testing. Drive
wheel tires shall be dried if necessary to prevent slippage.
(9) Vehicle Restraint. Testing shall not begin until the vehicle is restrained. Any
restraint system shall meet the requirements of §85.3(a)(5)(ii). In addition, the
parking brake shall be set for front wheel drive vehicles prior to the start of the test,
unless parking brake functions on front axle or if is automatically disengaged when
in gear.
(10) Vehicle Conditioning.
(i) Queuing Time. When a vehicle waits in a queue more than 20 minutes or
when a vehicle is shut-off for more than 5 minutes prior to the test, vehicle
conditioning shall be performed for 60 seconds, as specified in
§85.2(b)(10)(ii)(C). Emissions may be monitiored during this cycle and if
passing readings are obtained, as specified for the ASM cycle in §85.2(d),
then the cycle may be terminated and the respective ASM mode skipped.
Page 10 7/2/96 Test Procedures
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§85.2 §85.2
(ii) Discretionary Preconditioning. At the program's discretion, any vehicle may
be preconditioned using any of the following methods:
(A) Non-loaded Preconditioning. Increase engine speed to approximately
2500 rpm, for up to 4 minutes, with or without a tachometer.
(B) Loaded Preconditioning. Drive the vehicle on the dynamometer at 30
miles per hour for up to 240 seconds at road-load.
(C) ASM Preconditioning. Drive the vehicle on the dynamometer using
either mode of the ASM test as specified in §85.2(d).
(D) Transient Preconditioning. After maneuvering the vehicle onto the
dynamometer, drive a transient cycle consisting of speed, time,
acceleration, and load relationships such as the IM240.
(c) Equipment Preparation and Settings.
(1) Analyzer Warm-Up. Emission testing shall be locked out until the analyzer is
warmed-up and stable. The analyzer shall reach stability within 30 minutes from
startup. If an analyzer does not achieve stability within the allotted time frame, it
shall remain locked out from testing. The instrument shall be considered "warmed-
up" when the zero and span readings for HC, CO, NO, and CO2 have stabilized
within the accuracy values specified in §85.3(c)(3) for five minutes without
adjustment (this does not require span gas verification of warm-up, but provides the
quality assurance method for checking).
(2) Emission Sample System Purge. While a lane is in operation, the sample system
shall be continuously purged after each test for at least 15 minutes if not taking
measurements.
(3) Probe Insertion. The sample probe shall be inserted into the vehicle's tailpipe to a
minimum depth of 10 inches. If the vehicle's exhaust system prevents insertion to
this depth, a tailpipe extension shall be used.
(4) Multiple exhaust pipes. Exhaust gas concentrations from vehicle engines equipped
with functionally independent multiple exhaust pipes shall be sampled
simultaneously.
(5) Analyzer Preparation. The analyzer shall perform an automatic zero, an ambient air
reading, and an HC hang-up check prior to each test. This process shall occur within
two minutes of the start of the test.
(i) Automatic Gas Zero. The analyzer shall conduct automatic zero adjustments
using the zero gas specified in §85.4(d)(2)(iii). The zero adjustment shall
include the HC, CO, CO2, and NO channels. Bottled or generated zero air
may be used.
Page 11 7/2/96 Test Procedures
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§85.2 §85.2
(ii) Ambient Air Reading. Filtered ambient air shall be introduced to the
analyzer before the sample pump, but after the sample probe, hose, and
filter/water trap. The analyzer shall record the concentrations of the four
measured gases, but shall make no adjustments.
(iii) HC Hang-up Determination. The analyzer shall sample ambient air through
the probe to determine background pollution levels and HC hang-up. The
analyzer shall be locked out from testing until (1) the sample through probe
has less than 15 ppm HC, 0.02% CO, and 25 ppm NO; and, (2) the residual
HC in the sampling system (probe sample - ambient air reading) is less than 7
ppm.
(6) Cooling System. When ambient temperatures exceed 72°F, testing shall not begin
until the cooling system blower is positioned and activated. The cooling system
blower shall be positioned to direct air to the vehicle cooling system, but shall not be
directed at the catalytic converter.
(7) Dynamometer Warm-Up. The dynamometer shall be automatically warmed-up prior
to official testing and shall be locked out until it is warmed-up. Dynamometers
resting (not operated for at least 30 seconds and at least 15 mph) for more than 30
minutes shall pass the coast-down check specified in §85.4(b)(l) prior to use in
testing. As specified in §85.4(a)(2), control charts may be used to demonstrate
allowing a longer duration of inactivity before a required warm-up.
(8) Load Setting. Prior to each mode, the system shall automatically select the load
setting of the dynamometer from a look-up table supplied by EPA or the state.
(9) Engine Speed. Engine speed measurement equipment shall be attached on all 1996
and newer light duty vehicles and trucks, and in test-and-repair programs, engine
speed shall also be monitored on all pre-1996 vehicles. Starting in 1998, the SAE-
standardized OBD plug shall be used on 1996 and newer vehicles. Engine speed
measurement equipment shall meet the requirements of §85.3(c)(5).
(d) Test Procedures.
The test sequence shall consist of either a single ASM mode or both ASM modes described
in §85.2(d)(l) and (2), and may be performed in either order (with appropriate chnage in
transition requirements in §85.2(d)(l)(iv)). Vehicles that fail the first-chance test described
in §85.2(d) shall receive a second-chance test if the conditions in §85.2(e) apply. The test
timer shall start (tt=0) when the conditions specified in §85.2(c)(2) and §85.2(c)(3) are met
and the mode timer initiates as specified in §85.2(d)(l) or §85.2(d)(2). The test sequence
shall have an overall maximum test time of 290 seconds (tt=290). The test shall be
immediately terminated or aborted upon reaching the overall maximum test time.
(1) ASM5015Mode.
(i) The mode timer shall start (mt=0) when the dynamometer speed (and
corresponding power) is maintained within 15±1.0 miles per hour for 5
continuous seconds. If the inertia simulation error exceeds the tolerance
specified in §85.3(a)(4)(ii)(A) (or §85.3(a)(4)(ii)(B) if used) for more than 3
consecutive seconds after the mode timer is started, the test mode timer shall
Page 12 7/2/96 Test Procedures
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§85.2
§85.2
be set to mt=0. Should this happen a second time, the test shall be aborted.
The dynamometer shall apply the correct torque for 15.0 mph for the torque
at any testing speed within the tolerance of 15±1.0 miles per hour (i.e.,
constant torque load over speed range). The torque tolerance shall be ± 5%
of the correct torque at 15 mph.
(ii) The dynamometer power shall be automatically selected from an EPA-
supplied or EPA-approved look-up table, based upon the vehicle
identification information described in §85.2(a)(l). Vehicles not listed in the
look-up table and for which ETW is not available shall be tested using the
following default settings:
Default ASM5015 Actual Horsepower Settings
For 8.6" Dynamometers HP5015g
^Vehicle Type
^^umbe£_of_CyJiride
Sedans
Station Wagons
Mini-vans
Pickup Trucks
Sport/Utility
Full Vans
rs — ^ 3
7.9
8.1
10.2
9.6
10.1
10.3
4
11.4
11.7
14.1
13.1
13.4
13.9
5&6
13.8
13.8
15.8
16.4
15.5
17.7
8
16.4
16.1
17.9
19.2
19.4
19.6
>8
16.0
16.1
18.2
21.1
21.1
20.5
Default ASM5015 Actual Horsepower Settings
For 20" Dynamometers HP501520
^Vehicle Type
Number of Cylinders^-
Sedans
Station Wagons
Mini-vans
Pickup Trucks
Sport/Utility
Full Vans
3
8.1
8.3
10.4
9.8
10.5
10.8
4
11.8
12.1
14.5
13.4
13.8
14.4
5&6
14.3
14.2
16.3
16.8
15.9
18.2
8
16.9
16.6
18.5
19.8
19.9
20.2
>8
16.6
16.6
18.7
21.7
21.7
21.1
If the dynamometer speed or torque falls outside the speed or torque tolerance
for more than 2 consecutive seconds, or for more than 5 seconds total, the
mode timer shall reset to zero and resume timing. The minimum mode length
shall be determined as described in §85.2(d)(iii). The maximum mode length
shall be 90 seconds elapsed time (mt=90).
During the 10 second period used for the pass decision, the dynamometer
speed shall not fall more than 0.5 mph (absolute drop, not cumulative). If the
speed at the end of the 10 second period is more than 0.5 mph less than the
speed at the start of the 10 second period, testing shall continue until the
speed stabilizes enough to meet this criterion.
Page 13
7/2/96
Test Procedures
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§85.2 §85.2
The ten second emissions window shall be matched to the corresponding
vehicle speed trace time window. This shall be performed by subtracting the
nominal response time for the analyzers from the mode time to determine the
time for the corresponding vehicle speed.
(iii) The pass/fail analysis shall begin after an elapsed time of 25 seconds
(mt=25). A pass or fail determination shall be made for the vehicle and the
mode shall be terminated as follows:
(A) The vehicle shall pass the ASM5015 mode and the mode shall be
immediately terminated if, at any point between an elapsed time of 25
seconds (mt=25) and 90 seconds (mt=90), the 10 second running
average measured values for each pollutant are simultaneously less than
or equal to the applicable test standards described in §85.1 (a).
(B) The vehicle shall fail the ASM5015 mode and the mode shall be
terminated if the requirements of §85.2(d)(l)(iii)(A) are not satisfied by
an elapsed time of 90 seconds (mt=90).
(iv) Upon termination of the ASM5015 mode, the vehicle shall immediately
begin accelerating to the speed required for the ASM2525 mode. The
dynamometer torque shall smoothly transition during the acceleration period
and shall automatically reset to the load required for the ASM2525 mode as
specified in §85.2(d)(2)(i) once the roll speed specified in §85.2(d)(2)(i) is
achieved.
(2) ASM2525 Mode.
(i) The mode timer shall start (mt=0) when the dynamometer speed (and
corresponding power) are maintained within 25±1.0 miles per hour for 5
continuous seconds. If the inertia simulation error exceeds the tolerance
specified in §85.3(a)(4)(ii)(A) (or §85.3(a)(4)(ii)(B) if used) for more than 3
consecutive seconds after the mode timer is started, the test mode timer shall
be set to mt=0. Should this happen a second time, the test shall be aborted.
The dynamometer shall apply the correct torque for 25.0 mph for the torque
at any testing speed within the tolerance of 25±1.0 miles per hour (i.e.,
constant torque load over speed range). The torque tolerance shall be ± 5%
of the correct torque at 25 mph.
(ii) The dynamometer power shall be automatically selected from an EPA-
supplied or EPA-approved look-up table, based upon the vehicle
identification information described in §85.2(a)(l). Vehicles not listed in the
look-up table and for which ETW is not available shall be tested using the
following default settings:
Page 14 7/2/96 Test Procedures
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§85.2
§85.2
(iii)
Default ASM2525 Actual Horsepower Settings
For 8.6" Dynamometers HP25258
^Vehicle Type
Number of Cylinders^ 3 4 5&6 8 >8
Sedans 6.7 9.5 11.5 13.7 13.3
Station Wagons
Mini-vans
Pickup Trucks
Sport/Utility
Full Vans
6.8
8.8
8.0
8.8
9.0
9.7
11.7
10.9
11.2
11.6
11.5
13.2
13.6
12.9
14.7
13.4
14.9
16.0
16.1
16.3
13.3
15.3
17.8
17.8
17.2
Default ASM2525 Actual Horsepower Settings
For 20" Dynamometers HP252520
^Vehicle Type
^^umb^rj)f_CyJiride_
Sedans
Station Wagons
Mini-vans
Pickup Trucks
Sport/Utility
Full Vans
•c ^ J
6.9
7.0
8.9
8.1
8.9
9.1
4
10.1
10.4
12.5
11.4
11.8
12.5
5&6
12.3
12.2
14.0
14.4
13.6
15.5
8
14.5
14.2
15.9
16.9
17.1
17.3
>8
14.3
14.4
16.3
18.8
18.8
18.3
If the dynamometer speed or torque falls outside the speed or torque tolerance
for more than two consecutive seconds, or for more than 5 seconds total, the
mode timer shall reset to zero and resume timing. The minimum mode length
shall be determined as described in §85.2(d)(2)(iii). The maximum mode
length shall be 90 seconds elapsed time (mt=90).
During the 10 second period used for the pass decision, the dynamometer
speed shall not fall more than 0.5 mph (absolute drop, not cumulative). If the
speed at the end of the 10 second period is more than 0.5 mph less than the
speed at the start of the 10 second period, testing shall continue until the
speed stabilizes enough to meet this criterion.
The pass/fail analysis shall begin after an elapsed time of 25 seconds
(mt=25). A pass or fail determination shall be made for the vehicle and the
mode shall be terminated as follows:
(A) The vehicle shall pass the ASM2525 mode if, at any point between an
elapsed time of 25 seconds (mt=25) and 90 seconds (mt=90), the 10-
second running average measured values for each pollutant are
simultaneously less than or equal to the applicable test standards
described in §85.1 (a). If the vehicle passed the ASM5015 mode, as
described in §85.2(d)(l)(iii), the ASM2525 mode shall be terminated
upon obtaining passing scores for all three pollutants. If the vehicle
Page 15
7/2/96
Test Procedures
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§85.2 §85.2
failed the ASM5015 mode, the ASM2525 mode shall continue for an
elapsed time of 90 seconds (mt=90).
(B) The vehicle shall fail the ASM2525 mode and the mode shall be
terminated if the requirements of §85.2(d)(2)(iii)(A) are not satisfied by
an elapsed time of 90 seconds (mt=90).
(e) Second Chance Tests.
(1) If the vehicle fails the first-chance test, the test timer shall reset to zero (tt=0) and a
second-chance test shall be performed, except as noted below. The second-chance
test shall have an overall maximum test time of 145 seconds (tt=145) if one mode is
repeated, an overall maximum time of 290 seconds (tt=290) if two modes are
repeated.
(2) Repetition or extension of failed modes for two mode ASM tests. Except in the case
of vehicles subject to preconditioning specified in §85.2(b)(10(i), if at least 90
seconds of loaded preconditioning is performed, as specified in §85.2(b)(10)(ii), then
the second-chance test may be omitted.
(i) If the vehicle failed only the first mode (ASM5015) of the first chance test,
then that mode shall be repeated upon completion of the second mode
(ASM2525). The repeated mode shall be performed as described in
§85.2(d)(l) except that the provisions of §85.2(d)(l)(iv) shall be omitted.
The test will terminate when the mode ends or when the vehicle passes,
whichever occurs first.
(ii) If the vehicle is failing only the second mode (ASM2525) of the first chance
test, then the second mode shall not end at 90 seconds but shall continue for
up to 180 seconds. Mode and test timers shall not reset but rather continue
up to 180 seconds. The provisions of §85.2(d)(2) shall continue to apply
throughout the 180 second test period.
(iii) If the vehicle failed both modes (ASM5015 and ASM2525) of the first
chance test, then the vehicle shall receive a second-chance test for the
ASM5015. If the vehicle fails the second-chance ASM5015, then the vehicle
shall fail the test. Otherwise, the vehicle shall also receive a second-chance
ASM2525.
(3) Repetition of failed modes for single mode ASM tests.
(ii) If the vehicle is failing at the end of the mode then the test mode shall not end
at 90 seconds but shall continue for up to 180 seconds. Mode and test timers
shall not reset but rather continue up to 180 seconds. The provisions of
§85.2(d)(l) or §85.2(d)(2) shall continue to apply throughout the 180 second
test period.
Page 16 7/2/96 Test Procedures
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§85.3 §85.3
§85.3 Test Equipment Specifications
(a) Dynamometer Specifications.
(1) General Requirements
(i) Only one diameter of dynamometer shall be used in a program.
(ii) The dynamometer structure (e.g., bearings, rollers, pit plates, etc.) shall
accommodate all light-duty vehicles and light-duty trucks up to 8500 pounds
GVWR.
(iii) Dynamometer ASM load horsepower (HP5015 or HP2525) shall be
automatically selected based on the vehicle parameters in the test record.
(iv) All dynamometers shall have an identification plate permanently affixed
showing at a minimum, the dynamometer manufacturers name, the system
provider's name, production date, model number, serial number,
dynamometer type, maximum axle weight, maximum HP absorbed, roll
diameter, roll width, base inertia weight, and electrical requirements.
(v) Alternative dynamometer specifications or designs may be allowed if
proposed by a state and upon a determination by the Administrator that, for
the purpose of properly conducting an approved short test, the evidence
supporting such deviations show that proper vehicle loading will be applied.
(2) Power Absorption.
(i) Vehicle Loading. The vehicle loading used during the ASM driving cycles
shall follow the equation in §85.3(a)(2)(ii) at 15 and 25 mph. Unless
otherwise noted, any horsepower displayed during testing shall be expressed
as HP.
(ii) IHP = THP - PLHP - GTRL
HP = IHP + PLHP
Where:
HP = The actual Horsepower value contained in the look-up table for a
vehicle being tested (using the ASM5015 or 2525) on a
dynamometer with the specified diameter rollers. The actual
horsepower is the sum of the indicated horsepower and the
parasitic losses (PLHP)
IHP = Indicated Horsepower value set on the dynamometer.
THP = Total Horsepower for an ASM test includes indicated, tire losses,
and parasitics. This value is independent of roll size.
GTRL = Generic Tire/Roll Interface Losses at the specified speed (15 or
25 mph) on a dynamometer with the specified diameter rollers.
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§85.3 §85.3
PLHP = Parasitic Losses Horsepower due to internal dynamometer
friction. A value is specific to each individual dynamometer and
speed.
(iii) Range of Power Absorber. The range of the power absorber shall be
sufficient to simulate the load required to perform an ASM5015 and an
ASM2525 on all light-duty vehicles and light-duty trucks up to 8500 pounds
GVWR. The power absorber shall absorb, at 14 mph and above, a minimum
of 25 horsepower continuously for a steady-state test of at least 5 minutes,
with 3 minutes between each test.
(iv) Parasitic Losses. The parasitic losses (PLHP) in each dynamometer system
(including but not limited to windage, bearing friction, and system drive
friction) shall be characterized at 15 and 25 mph upon initial acceptance, and
during each dynamometer calibration. The parasitic power losses shall be
determined as indicated in §85.4(b)(2).
(v) Power Absorber. Only electric power absorbers shall be used unless
alternatives are proposed by the state and approved by the Administrator.
The power absorber shall be adjustable in 0.1 hp increments at both 15 MPH
and 25 MPH. The accuracy of the power absorber (PAU + parasitic losses)
shall be ±0.25 horsepower or ±2% of required power, whichever is greater, in
either direction of rotation. For field auditing the accuracy shall be ±0.5
horsepower.
(vii) Accuracy Over the Operating Range. The dynamometer's accuracy when
warm shall not deviate more than ±0.5 horsepower over the full ambient
operating range of 35°F to 110°F. This may be accomplished by intrinsic
design or by software correction techniques. At any constant temperature,
the dynamometer shall have an accuracy of ±0.5 horsepower within 15
seconds of the start of the test, and shall have an accuracy of ±0.25
horsepower within 30 seconds of the start of the test. For temperatures
outside the specified range, the dynamometer shall provide correction or
proceed with a manufacturer warm-up sequence until full warm condition has
been reached.
(3) Rolls.
(i) Size and Type. The dynamometer shall be equipped with twin rolls. The
rolls shall be electrically or mechanically coupled side-to-side and front-to-
rear. The dynamometer roll diameter shall be between 8.5 and 21.0 inches.
The spacing between the roll centers shall comply with the equation in
§85.3(a)(3)(ii) to within 0.5 inches and -0.25 inches of the calculated value.
Fixed dynamometer rolls shall have an inside track width of no more than 30
inches and outside track width of at least 100 inches. Rolls moveable from
side-to-side may be used if adequate measures are taken to prevent tire
damage from lateral vehicle movement and the dynamometer sufficiently
accommodates track widths of the full range of vehicles to be tested on the
dynamometer. Alternative track widths, roll sizes, and number of rolls may
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§85.3 §85.3
be used if approved by the state and the Administrator and if adequate
measures are taken to prevent tire damage from lateral vehicle movement and
the dynamometer sufficiently accommodates track widths of the full range of
vehicles to be tested on the dynamometer.
(ii) Roll Spacing = (24.375+D) * Sin 31.5153
D = dynamometer roll diameter.
Roll spacing and roll diameter are expressed in inches.
(iii) Design. The roll size, surface finish, and hardness shall be such that tire
slippage is minimized under all weather conditions; that water removal is
maximized; that the specified accuracy of the distance and speed
measurements are maintained; and that tire wear and noise are minimized.
(4) Inertia.
(i) Base Inertia. The dynamometer shall be equipped with mechanical
flywheel(s) or with full inertia simulation providing a total base inertia weight
of 2000 pounds ±40 pounds. Any deviation from the 2000 pound base inertia
shall be quantified and the coast-down time shall be corrected accordingly.
Any deviation from the stated inertia shall be quantified and the inertia
simulation shall be corrected accordingly. The actual inertia weight shall be
marked on the ID plate required in §85.3(a)(l)(iv).
(ii) Inertia/Inertia Simulation. The dynamometer shall be capable of conducting,
at a minimum, diagnostic level transient inertia simulations with an
acceleration rate between 0 and 3.3 miles per hour per second with a
minimum load (power) of 25 horsepower at 14 mph over the inertia weight
range of 2000 pounds to 6000 pounds. For the diagnostic level inertia
simulation, the 25 horsepower criterion is a requirement on acceleration only,
while for the full inertia simulation option, the requirement is for both
acceleration and deceleration. Mechanical inertia simulation shall be
provided in 500 pound increments; electric inertia simulation shall be
provided in 1 pound increments. Any deviation from the stated inertia shall
be quantified and the inertia simulation shall be corrected accordingly.
Mechanical or electrical inertia simulation, or a combination of both, may be
used, subject to review and approval by the state.
(A) Diagnostic Level Simulation.
1. System Response. The torque response to a step change shall be
at least 90% of the requested change within 300 milliseconds.
2. Simulation Error. An inertia simulation error (ISE) shall be
continuously calculated any time the actual dynamometer speed is
between 10 MPH and 60 MPH. The ISE shall be calculated by the
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§85.3 §85.3
equation in §85.3(a)(4)(ii)(C), and shall not exceed 3% of the
inertia weight selected (IWs) for the vehicle under test.
(B) Full Inertia Simulation. (Recommended Option)
1. System Response. The torque response to a step change shall be
at least 90% of the requested change within 100 milliseconds after
a step change is commanded by the dynamometer control system,
and shall be within 2% of the commanded torque by 300
milliseconds after the command is issued. Any overshoot of the
commanded torque value shall not exceed 25% of the torque
value.
2. Simulation Error. An inertia simulation error (ISE) shall be
continuously calculated any time the actual dynamometer speed is
between 10 MPH and 60 MPH. The ISE shall be calculated by the
equation in §85.3(a)(4)(ii)(C), and shall not exceed 1% of the
inertia weight selected (IWS) for the vehicle under test.
(C) Inertia Simulation Error Calculation.
ISE = [(IWS - It) / (IWS)] * 100
It = Im + (^) p (Fm-Frl)dt
Where:
ISE = Inertia Simulation Error
IWS = Inertia Weight Selected
It = Total inertia being simulated by the dynamometer
(kg)
It (lb force) = It (kg) * 2.2046
Im = Base (mechanical inertia of the dynamometer (kg)
V = Measured roll speed (m/s)
Fm = Force measured by the load cell (translated to the roll
surface) (N)
Fri = Road load force (N) required by IHP at the measure
roll speed (V)
t = Time (sec)
(5) Other Requirements.
(i) Vehicle Speed. The measurement of roll speed shall be accurate within 0.1
mph over the full operating range. The dynamometer shall accommodate
vehicle speeds of up to 60 mph.
(ii) Vehicle Restraint. The vehicle shall be restrained during the driving cycle.
The restraint system shall be designed to insure that vertical and horizontal
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§85.3 §85.3
force on the drive wheels does not significantly affect emission levels. The
restraint system shall allow unobstructed vehicle ingress and egress and shall
be capable of safely restraining the vehicle under all reasonable operating
conditions without damaging the suspension system.
(iii) Vehicle Cooling. The test system shall provide for a method to prevent
overheating of the vehicle. The test shall be conducted with the hood open
and the cooling system activated when ambient temperature exceeds 72°F.
The cooling method used shall direct air to the test vehicle's cooling system.
The cooling system capacity shall be at least 3000 SCFM within 12 inches of
the intake to the vehicle's cooling system. The cooling system shall avoid
improper cooling of the catalytic converter.
(iv) Four-Wheel Drive. If used, four-wheel drive dynamometers shall insure the
application of correct vehicle loading as defined in §85.3(a)(2), shall not
damage the four wheel drive system of the vehicle, and shall accomodate
vehicles equipped with anti-lock brakes and/or traction control. Front and
rear wheel rolls shall maintain speed synchronization within 0.2 mph.
(v) Installation. Either in-floor or above ground installations of the dynamometer
are acceptable. In all cases, installation must be performed so that the test
vehicle is approximately level (±5°) while on the dynamometer during
testing.
(vi) Augmented Braking. Dynamometers shall apply augmented braking on
major decelerations during transient drive cycles, if such cycles are used in
the program. The dynamometer software shall provide a signal output to
inform the operator when augmented braking is activated.
(b) Emission Sampling System.
(1) The sampling system shall be designed to insure durable, leak free operation and be
easily maintained. Materials that are in contact with the gases sampled shall not
contaminate or change the character of the gases to be analyzed, including gases
from vehicles not fueled by gasoline (except diesels). The system shall be designed
to be corrosion-resistant and be able to withstand typical vehicle exhaust
temperatures when the vehicle is driven through the ASM test cycle for 290 seconds.
(2) The sampling system shall draw exhaust gas from the vehicle, shall remove
particulate matter and aerosols from the sampled gas, shall drain condensed water
from the sample if necessary, and shall deliver the resultant gas sample to the
analyzers/sensors for analysis and then deliver the analyzed sample directly outside
the building. The sampling system shall, at a minimum, consist of a tailpipe probe,
flexible sample line, water removal system, a particulate trap, sample pump, and
flow control components.
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§85.3 §85.3
(3) Sample Probe.
(i) Insertion. The sample probe shall allow at least a 16 inch insertion depth of
the sample point into the vehicle's exhaust. In addition, the probe shall be
inserted at least 10 inches into the vehicle's exhaust. Use of a tailpipe
extension is permitted as long as the extension does not change the exhaust
back pressure by more than ±1.0 inch of water pressure.
(ii) Retention. The probe shall incorporate a positive means of retention to
prevent it from slipping out of the tailpipe during use. High through-put test
systems may use alternative means to insure probe retention.
(iii) Flexibility. The probe shall be designed so that the tip extends 16 inches into
the tailpipe. The probe tip shall be shielded so that debris is not scooped up
by the probe when it is inserted into the tailpipe. High through-put test
systems may use alternative means to insure adequate probe insertion.
(iv) Probe Tip. Probe tips shall be designed and constructed to prevent sample
dilution.
(v) Materials. All materials in contact with exhaust gas prior to and throughout
the measurement portion of the system shall be unaffected by and shall not
affect the sample (i.e., the materials shall not react with the sample, and they
shall not taint the sample). Acceptable materials include stainless steel,
Teflon, silicon rubber, and Tedlar. Dissimilar metals with thermal expansion
factors of more than 5% shall not be used in either the construction of probes
or connectors. The sample probe shall be constructed of stainless steel or
other non-corrosive, non-reactive material which can withstand exhaust gas
temperatures at the probe tip of up to 1,100_F for 10 minutes.
(vi) System Hoses and Connections. Hoses and all other sample handling
components must be constructed of, or plated with a non-reactive, non-
corrosive, high temperature material which will not affect, or be affected by,
the exhaust constituents and tracer gases.
(vii) Dual Exhaust. The sample system shall provide for the testing of dual
exhaust equipped vehicles. When testing a vehicle with functional dual
exhaust pipes, a dual sample probe of a design certified by the analyzer
manufacturer to provide equal flow in each leg shall be used. The equal flow
requirement is considered to be met if the flow rate in each leg of the probe
has been measured under two sample pump flow rates (the normal rate and a
rate equal to the onset of low flow), and if the flow rates in each of the legs
are found to be equal to each other (within 15% of the flow rate in the leg
having lower flow).
(4) Particulate Filter. The particulate filter shall be capable of trapping 97% of all
particulate and aerosols 5 microns or larger. The filter element shall not absorb or
adsorb hydrocarbons. The filter housing shall be transparent or translucent to allow
the operator to observe the filter element's condition without removing the housing.
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§85.3 §85.3
The filter element shall be easily replaceable and shall provide for reliable sealing
after filter element changes.
(5) Water Trap. The water trap shall be sized to remove exhaust sample water from
vehicles fueled with gasoline, propane, compressed natural gas, reformulated
gasoline, alcohol blends or neat, and oxygenated fuels. The filter element, bowl and
housing shall be inert to these fuels as well as to the exhaust gases from vehicles
burning these fuels. The condensed water shall be drained from the water trap's
bowl either continuously or automatically on a periodic basis such that the following
performance requirement is maintained. Sufficient water shall be trapped, regardless
of fuel, to prevent condensation in the sample system or in the optical bench's
sample cell.
(6) Low Flow Indication. The analyzer shall lock out official testing when the sample
flow is below the acceptable level. The sampling system shall be equipped with a
flow meter (or equivalent) that shall indicate sample flow degradation when
measurement error exceeds 3% of the gas value used for checking, or causes the
system response time to exceed 13 seconds to 90 percent of a step change in input
(excluding NO), whichever is less.
(7) Exhaust Ventilation System. The high quantities of vehicle emissions generated
during loaded mode testing shall be properly vented to prevent buildup of hazardous
concentrations of HC, CO, CO2 and NOx. Sufficient ventilation shall be provided in
the station to maintain HC, CO, CO2 and NO levels below OSHA standards.
(i) The ventilation system shall discharge the vehicle exhaust outside the
building.
(ii) The flow of the exhaust collection system shall not cause dilution of the
exhaust at the sample point in the probe.
(iii) The flow of the exhaust collection system shall not cause a change of more
than ±1.0 inches of water pressure in the vehicle's exhaust system at the
exhaust system outlet.
(c) Analytical Instruments.
(1) General Requirements.
(i) Measured Gases. The analyzer system shall consist of analyzers for HC, CO,
NO, and CO2, (O2 optional) and digital displays for exhaust concentrations
of HC, CO, NO, and CO2, and for vehicle speed.
(ii) Emission Accuracy. The system shall ensure that the analytical system
provides an accurate accounting of the actual exhaust emissions produced
during the test, taking into consideration the individual channel accuracies,
repeatabilities, interference effects, sample transport times, and analyzer
response times.
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§85.3 §85.3
(iii) Sample Rate. The analyzer shall be capable of measuring exhaust
concentrations of the gases specified in §85.3(c)(l)(i) at a minimum rate of
once per second.
(iv) Alternative Equipment. Alternative analytic equipment specification,
materials, designs, or detection methods may be allowed if proposed by a
state and upon a determination by the Administrator, that for the purpose of
properly conducting a test, the evidence supporting such deviations will not
significantly affect the proper measurement of emissions.
(2) Performance Requirements.
(i) Temperature Operating Range. The analyzer system and all associated
hardware shall operate within the performance specifications described in
§85.3(c)(3) at ambient air temperatures ranging from 35_F to 110_F.
Analyzers shall be designed so that adequate air flow is provided around
critical components to prevent overheating (and automatic shutdown) and to
prevent the condensation of water vapor which could reduce the reliability
and durability of the analyzer. The analyzer system shall otherwise include
necessary features to keep the sampling system within the specified range.
(ii) Humidity Operating Range. The analyzer system and all associated hardware
shall operate within the performance specifications described in §85.3(c)(3)
at a minimum of 85% relative humidity throughout the required temperature
range.
(iii) Interference Effects. The interference effects for non-interest gases shall not
exceed ±4 ppm for hydrocarbons, ±0.02% for carbon monoxide, ±0.20% for
carbon dioxide, and ±20 ppm for nitric oxide when using the procedure
specified in §85.4(d)(5)(iv). Corrections for collision-broadening effects of
combined high CO and CO2 concentrations shall be taken into account in
developing the factory calibration curves, and are included in the accuracy
specifications.
(iv) Barometric Pressure Compensation. Barometric pressure compensation shall
be provided. Compensation shall be made for elevations up to 6000 feet
(above mean sea level). At any given altitude and ambient conditions
specified in §85.3(c)(2)(i) and (ii), errors due to barometric pressure changes
of ±2 inches of mercury shall not exceed the accuracy limits specified in
§85.3(c)(3).
(v) System Lockout During Warm-up. Functional operation of the gas sampling
unit shall remain disabled through a system lockout until the instrument
meets stability and warm-up requirements. The instrument shall be
considered "warm" when the zero and span readings for HC, CO, NO, and
CO2 have stabilized, within the accuracy values specified in §85.3(c)(3) for
five minutes without adjustment.
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§85.3 §85.3
(vi) Zero Drift Lockout. If zero or span drift cause the optical bench signal levels
to move beyond the adjustment range of the analyzer, the system shall be
locked out from testing.
(vii) Electromagnetic Isolation and Interference. Electromagnetic signals found in
an automotive service environment shall not cause malfunctions or changes
in the accuracy in the electronics of the analyzer system. The instrument
design shall ensure that readings do not vary as a result of electromagnetic
radiation and induction devices normally found in the automotive service
environment, including high energy vehicle ignition systems, radio frequency
transmission radiation sources, and building electrical systems.
(viii) Vibration and Shock Protection. System operation shall be unaffected by the
vibration and shock encountered under the normal operating conditions
encountered in an automotive service environment.
(ix) Propane Equivalency Factor. The nominal PEF range shall be between 0.490
and 0.540. For each audit/calibration point, the nominal PEF shall be
conveniently displayed for the quality assurance inspector and other
authorized personnel. If an optical bench must be replaced in the field, any
external labels shall be changed to correspond to the nominal PEF of the new
bench. The analyzer shall incorporate an algorithm relating PEF to HC
concentration. Corrections shall be made automatically. The corrected PEF
value may cover the range of 0.470 to 0.560.
(x) System Response Requirements. The response time from the probe to the
display for HC, CO, and CO2 analyzers shall not exceed 8 seconds for 90%
of a step change in input, nor shall it exceed 12 seconds to 95% of a step
change in input. The response time for a step change in O2 from 20.9% O2
to 0.1% O2 shall be no longer than 40 seconds. For NO analyzers, the
response time shall not exceed 12 seconds for 90% of a step change in input.
The response time for a step change in NO from a stabilized reading to 10%
of that reading shall be no longer than 12 seconds.
(3) Detection Methods. Instrument Ranges. Accuracy, and Repeatability.
(i) Hydrocarbon Analysis. Hydrocarbon analysis shall be determined by non-
dispersive infrared (NDIR) analyzer. The analyzer shall cover at least the
range of 0 ppm HC to 9999 ppm HC, where ppm HC is parts per million of
hydrocarbon volume as hexane. The accuracy of the instrument from 0-2000
ppm HC shall be ±3% of point or 4 ppm C6, whichever is greater. The
accuracy of the instrument between 2001 ppm HC and 5000 ppm HC shall be
at least ±5% of point. The accuracy of the instrument between 5001 ppm HC
and 9999 ppm HC shall be at least ±10% of point. The instrument shall
comply with the quality control specifications in §85.4(d).
(ii) Carbon Monoxide Analysis. Carbon monoxide analysis shall be determined
by non-dispersive infrared (NDIR) analyzer. The analyzer shall cover at least
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§85.3 §85.3
the range of 0.00 % CO to 14.00% CO, where % CO is % volume CO. The
accuracy of the instrument between 0.01% and 10.00% CO shall be ±3% of
point or 0.02% CO, whichever is greater. The accuracy of the instrument
between 10.01% and 14.00% shall be at least ±5% of point. The instrument
shall comply with the quality control specifications in §85.4(d).
(iii) Carbon Dioxide Analysis. Carbon dioxide analysis shall be determined by
non-dispersive infrared (NDIR) analyzer. The analyzer shall cover at least
the range of 0.0 % CO2 to 18.0% CO2. The accuracy of the instrument
between 0.01% and 16.00% CO2 shall be ±3% of point or 0.3% CO2,
whichever is greater. The accuracy of the instrument between 16.01% and
18.00% shall be at least ±5% of point. The instrument shall comply with the
quality control specifications in §85.4(d).
(iv) Nitric Oxide Analysis. The analyzer shall cover at least the range of 0 ppm
NO to 5000 ppm NO, where ppm NO is parts per million nitric oxide. The
accuracy of the instrument between 0 and 4000 ppm shall be at least ±4% of
point or 25 ppm NO, whichever is greater. The accuracy of the instrument
between 4001 and 5000 ppm shall be at least ±8% of point. The instrument
shall comply with the quality control specifications in §85.4(d).
(v) Oxygen Analysis, (optional) If an oxygen analyzer is included, the analyzer
shall cover at least the range of 0.0% 02 to 25.0% 02. The accuracy of the
instrument over this range shall be at least 5% of point or ±0.1% O2,
whichever is greater. The instrument shall comply with the quality control
specifications in §85.4(d).
(vi) Repeatability. The repeatability for the HC analyzer in the range of 0-1400
ppm HC shall be 2% of point or 3 ppm HC absolute, whichever is greater. In
the range of 1400-2000 ppm HC, the repeatability shall be 3% of point. The
repeatability for the CO analyzer in the range of 0-7.00% CO shall be 2% of
point or 0.02% CO absolute, whichever is greater. In the range of 7.00% to
10.00% CO, the repeatability shall be 3% of point. The repeatability for the
CO2 analyzer in the range of 0-10.0% CO2 shall be 2% of point or 0.1% CO2
absolute, whichever is greater. In the range of 10.0% to 16.0% CO2, the
repeatability shall be 3% of point. The repeatability of the NO analyzer shall
be 3% of point or 20 ppm NO, whichever is greater. The repeatability of the
O2 analyzer shall be 3% of point or 0.1% O2, whichever is greater.
(vii) Rounding Rule. Rounding beyond the decimal places shown in §85.3(c)(3)
shall follow the standard mathematical practice of going to the next higher
number for any numerical value of five or more. This shall also hold true for
pass/fail decisions. For example, if 2.00% CO passes and 2.01% CO fails,
and the reading is 2.0049%, the value shall be rounded down and the decision
shall be a pass. If the reading is 2.0050, the value shall be rounded up and
the decision shall be a fail. The value displayed and printed on the test report
shall be consistent with the value used for the pass/fail decision.
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(4) Ambient Conditions. The current relative humidity, dry-bulb temperature, and
barometric pressure shall be measured and recorded prior to the start of every
inspection in order to calculate Kh (nitric oxide correction factor §85.1(b)(l)(v)).
(i) Relative Humidity. The relative humidity measurement device shall cover
the range from 5% to 95% RH, between 35_F - 110_F, with a minimum
accuracy of ±3% RH. Wet bulb thermometers shall not be used.
(ii) Dry-bulb Temperature. The dry-bulb temperature device shall cover the
range from 0_F - 140_F with a minimum accuracy of 3_F.
(iii) Barometric Pressure. The barometric pressure measurement device shall
cover the range from 610 mm Hg - 810 mm Hg absolute (24-32 inches), and
35_F - 110_F, with a minimum accuracy of ±3% of point or better.
(5) Engine Speed Detection. The analyzer shall utilize a tachometer capable of
detecting engine speed in revolutions per minute (rpm) with a 0.5 second response
time and an accuracy of ±3% of the true rpm. Starting in 1998, on vehicles equipped
with onboard diagnostic (OBD) systems, the engine speed shall be taken by
connecting to the SAE standardized OBD link on 1996 and newer vehicles. RPM
readings shall be recorded on a second-by-second basis for the 10 second period
upon which the pass/fail basis is based.
(6) OBD Fault Code Retrieval. Starting in 1998, the system shall include the hardware
and software necessary to access the onboard computer systems on 1996 and newer
vehicles, determine OBD readiness, and recover stored fault codes using the SAE
standardized link.
(d) Automated Test Process Software and Displays.
(1) Software. The testing process, data collection, and quality control features of the
analyzer system shall be automated to the greatest degree possible. The software
shall automatically select the emission standards and set the vehicle load based on an
EPA-provided or approved look-up table. Vehicle identification information shall be
derived from a database accessed over a real-time data system to a host computer
system. Entry of license plate and all or part of the VIN shall be sufficient to access
the vehicle record. Provision shall be made for manual entry of data for vehicles not
in the host computer system.
(2) Test and mode timers. The analyzer shall be capable of simultaneously determining
the amount of time elapsed in a test (overall test time), and in a mode within that test
(mode time).
(3) Clocks and Timers. The clock used to check the coast-down time shall be accurate
to within 0.1% of reading between 0.5 and 100 seconds, with a resolution of 0.001
seconds. The test mode timers used shall be accurate to within 0.1% of reading
between 10 and 1000 seconds with a resolution of 0.1 seconds.
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§85.3 §85.3
(4) Driver's Aid. The system shall be equipped with a driver's aid that shall be clearly
visible to the driver as the test is performed. The aid shall continuously display the
required speed, the number of seconds into the test mode, the driver's actual
speed/time performance (a display showing the deviation between set-point and
actual driving trace), engine RPM, the use of augmented braking, and necessary
prompts and alerts. The driver's aid shall also be capable of displaying test and
equipment status and other messages as required. Dynamic information being
displayed shall be refreshed at a minimum rate of twice per second. Emissions
values shall not be displayed during official testing.
(5) Minimum Analyzer Display Resolution. The analyzer electronics shall have
sufficient resolution to achieve the following:
HC 1
NO 1
CO 0.01
CO2 0.1
O2 0.1
RPM 10
Speed 0.1
Load 0.1
Relative Humidity 1
Dry Bulb Temperature 1
Barometric Pressure 1
ppm HC as hexane
ppmNO
%CO
% CO2
% O2 (optional)
RPM
mph
hp
%RH
_F
mm HG
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§85.4 §85.4
§85.4 Quality Control Requirements
(a) General Requirements
(1) Minimums. The frequency and standards for quality control specified here are
minimum requirements, unless modified as specified in §85.4(a)(2). Greater
frequency or tighter standards may be used as needed.
(2) Statistical Process Control. Reducing the frequency of the quality control checks,
modifying the procedure or specification, or eliminating the quality control checks
altogether may be allowed if the state demonstrates and the Administrator
determines, for the purpose of properly conducting an approved short test, that
sufficient Statistical Process Control (SPC) data exist to make a determination, that
the SPC data support such action, and that taking such action will not significantly
reduce the quality of the emissions measurements. Should emission measurement
performance or quality deteriorate as a result of allowing such actions, the approval
shall be suspended and the frequencies, procedures specifications, or checks
specified here or otherwise approved shall be reinstated, pending further
determination by the Administrator.
(b) Dynamometer
(1) Coast Down Check.
(i) The calibration of each dynamometer shall be automatically checked every
72 hours in low volume stations (less than 4000 tests per year) and daily in
high volume stations by a dynamometer coast-down procedure equivalent to
§86.118-78 (for reference see National Vehicle and Fuel Emission
Laboratory's Testing Services Division test procedure TP-302A and TP-202)
between the speeds of 30-20 mph if the ASM2525 is used and 20-10 mph if
the ASM5015 is used. All rotating dynamometer components shall be
included in the coast-down check. Speed windows smaller than ± 5 mph may
be used provided that they show the same calibration capabilities.
(ii) The base dynamometer inertia (2000 pounds) shall be checked at two
random horsepower settings for each speed range. The two random
horsepower settings shall be between 8.0 and 18.0 horsepower. A shunt
resistor for a load cell performance check shall not be used.
(iii) The coast-down procedure shall use a vehicle off-dynamometer type method
or equivalent. Using a vehicle to bring the dynamometer up to speed and
removing the vehicle before the coast-down shall not be permitted. If either
the measured 30-20 mph coast-down time or 20-10 mph coast-down time is
outside the window bounded by the Calculated Coast-Down Time (CCDT)
(seconds) ±7% then it shall be locked out for official testing purposes until
recalibration allows a passing value.
(A) Randomly select an IHP2525 value that is between 8.0 hp and 18.0 hp
and set dynamometer PAU to this value.
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§85.4
§85.4
(B)
Coast-down dynamometer from 30-20 mph.
CCDT
•0.5JHDIW
32.2
' V20 >
25 mph = 550 * (IHP2525 + PLHP25)
Where:
DIW
V
30
V20
IHP2525
PLHP25
= Dynamometer Inertia Weight. Total "inertia"
weight of all rotating components in dynamometer.
= Velocity in feet/sec at 30 mph.
= Velocity in feet/sec at 20 mph.
= Randomly selected ASM2525 indicated
horsepower.
= Parasitic Horsepower for specific dynamometer at
25 mph.
Randomly select an IHP5Q15 value that is between 8.0 hp and 18.0 hp
and set dynamometer PAU to this value.
Coast-down dynamometer from 20-10 mph.
CCDT
•0.5JHDIW
32.2
2,
10 >
15 mph = 550 * (IHP5Q15 +
Where:
DIW
V,
20
V
10
IHP5015
PLHPis
(2) Parasitic Value Calculations.
= Dynamometer Inertia Weight. Total "inertia"
weight of all rotating components in dynamometer.
= Velocity in feet/sec at 20 mph.
= Velocity in feet/sec at 10 mph.
= Randomly selected ASM5015 indicated
horsepower.
= Parasitic Horsepower for specific dynamometer at
15 mph.
(i) Parasitic losses shall be calculated using the following equations at 25 and 15
mph whenever a coast-down check is performed. The indicated horsepower
(IHP) shall be set to zero for these tests. This is only necessary if the coast-
down values do not verify in §85.4(b)(l)(iii) above.
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§85.4
§85.4
(ii) Parasitic losses at 25 mph for a dynamometer with specified diameter rollers.
PLHP25
32.2
' V
20
550 * (ACDT)
Where:
DIW = Dynamometer Inertia Weight. Total "inertia"
weight of all rotating components in dynamometer.
V^Q = Velocity in feet/sec at 30 mph.
V2Q = Velocity in feet/sec at 20 mph.
ACDT = Actual coast-down time required for dynamometer to
coast from 30 to 20 mph.
(iii) Parasitic losses at 15 mph for a dynamometer with specified diameter rollers.
PLHPis
32.2
' V
10
550 * (ACDT)
Where:
DIW = Dynamometer Inertia Weight. Total "inertia"
weight of all rotating components in dynamometer.
V2Q = Velocity in feet/sec at 20 mph.
Vi Q = Velocity in feet/sec at 10 mph.
ACDT = Actual coast-down time required for dynamometer to
coast from 20 to 10 mph.
(3) Roll Speed. Roll speed and roll counts shall be checked at least once per week by an
independent means (e.g., photo tachometer). Deviations greater than ±0.2 mph or a
comparable tolerance in roll counts shall require corrective action. Alternatively, a
redundant roll speed transducer independent of the primary transducer may be used
in lieu of the weekly comparison. Accuracy of redundant systems shall be checked
bimonthly.
(4) Load Measuring Device. If the dynamometer fails a coast-down check or requires a
recalibration for any other reason, the load measuring device shall be checked using
a dead-weight method or an equivalent procedure proposed by the state and
approved by the Administrator. The check shall cover at least three points over the
range of loads used for vehicle testing. Dead weights shall be traceable to the
National Institute of Standards (NIST) and shall be accurate to within ±0.1%. The
dynamometer shall provide an automatic load measuring device calibration and
verification feature.
(5) Acceptance Check.
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§85.4 §85.4
(i) Load Cell Verification (if equipped). This test confirms the proper operation
of the dynamometer load cell and associated systems. Weights in the proper
range shall be supplied by the system supplier. Weights shall be NIST
traceable to 0.1% of point.
(A) Calibrate the load cell according to the manufacturer's direction.
(B) Using a dead weight method, load the test cell to 20%, 40%, 60%, and
80% (in ascending order) of the range used for ASM testing. Record
the readings for each weight. Remove the weights in the same steps
(descending order) and record the results.
(C) Perform steps A through B two more times (total of three). Calculate
the average value for each weight. Multiply each average weight from
E by the length of the torque arm.
(D) Acceptance Criteria: The difference for each reading from the weight
shall not exceed 1% of full scale.
(ii) Speedometer Verification. This test confirms the accuracy of the
dynamometer's speedometer.
(A) Set dynamometer speed to 15 mph. Independently measure and record
dynamometer speed. Repeat at 25 mph.
(B) Acceptance Criteria: The difference for each reading from set
dynamometer speed shall not exceed 0.2 mph.
(iii) Parasitics Verification. Parasitic losses shall be calculated using the
following equations at 25 and 15 mph . The indicated horsepower (IHP)
shall be set to zero for these tests. Using time versus speed data from the
system, calculate PLHP for 25 mph and 15 mph.
(A) Parasitic losses at 25 mph for a dynamometer with specified diameter
rollers.
2 2
32.2 j (V30 ' V20 )
PLHP25 = 550 * (CDT)
Where:
DIW = Dynamometer Inertia Weight. Total "inertia"
weight of all rotating components in dynamometer.
VOQ = Velocity in feet/sec at 30 mph.
V2Q = Velocity in feet/sec at 20 mph.
CDT = Coast-down time required for dynamometer to coast
from 30 to 20 mph.
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§85.4 §85.4
(B) Parasitic losses at 15 mph for a dynamometer with specified diameter
rollers.
f°-5 * DIW^ * (v 2 v 2,
I 32.2 j (V20 ' V10 >
PLHPis =
Where:
DIW = Dynamometer Inertia Weight. Total "inertia"
weight of all rotating components in dynamometer.
V^Q = Velocity in feet/sec at 20 mph.
VJQ = Velocity in feet/sec at 10 mph.
CDT = Coast-down time required for dynamometer to coast
from 20 to 10 mph.
(C) Acceptance Criteria: The difference between the externally calculated
value and the machine calculated value shall not exceed 0.25 HP.
(iv) Verify Coast-Down. The coast-down procedure shall use a vehicle off-
dynamometer type method or equivalent. Using a vehicle to bring the
dynamometer up to speed and removing the vehicle before the coast-down
shall not be permitted.
(A) Randomly select an IHP2525 value that is between 8.0 hp and 18.0 hp
and set dynamometer PAU to this value.
Coast-down dynamometer from 30-20 mph.
0-5 * DIW^ , 2 v 2,
32.2 ) (V30 ' V20 >
CCDT@25 mph = 550 * (IHP2525 + PLHP25-yy)
Where:
DIW = Dynamometer Inertia Weight. Total "inertia"
weight of all rotating components in dynamometer.
VOQ = Velocity in feet/sec at 30 mph.
V2Q = Velocity in feet/sec at 20 mph.
IHP2525 = Randomly selected ASM2525 indicated
horsepower.
PLHP25 = Parasitic Horsepower for specific dynamometer at
25 mph.
(B) Randomly select an IHP5015 value that is between 8.0 hp and 18.0 hp
and set dynamometer PAU to this value.
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§85.4 §85.4
Coast-down dynamometer from 20-10 mph.
2,
0.5 *
32.2 20 ' 10 >
CCDT@ 1 5 mph = 550 * (IHP5015yy + PLHPi5_yy)
Where:
DIW = Dynamometer Inertia Weight. Total "inertia"
weight of all rotating components in dynamometer.
V2Q = Velocity in feet/sec at 20 mph.
Vi Q = Velocity in feet/sec at 10 mph.
IHP5015 = Randomly selected ASM50 15 indicated
horsepower.
PLHP15 = Parasitic Horsepower for specific dynamometer at
15 mph.
(C) Acceptance Criteria: The measured 30-20 mph coast-down time and
the 20-10 mph coast-down time must be inside the window bounded by
CCDT (seconds) ± 7%.
(c) Emission Sampling System.
(1) Leak Check. The entire sample system shall be checked for vacuum leaks on a daily
basis and proper flow on a continuous basis. This may be accomplished using a
vacuum decay method, reading a span gas, or other methods proposed by a state and
approved by the Administrator. The analyzer shall not allow an error of more than
1% of reading using the high-range span gas described in §85.4(d)(2)(iii)(C). The
analyzer shall be locked out from testing if the leak check is not performed when due
or fails to pass the check.
(2) Dilution. The flow rate on the analyzer shall not cause more than 10% dilution
during sampling of exhaust of a 1.6 liter engine a normal idle. Ten percent dilution
is defined as a sample of 90% exhaust and 10% ambient air.
(3) Dilution Acceptance Test.
(i) Set vehicle with 1.6 liter maximum engine displacement at factory -
recommended idle speed, OEM configuration exhaust system, transmission in
neutral, hood up (a fan to cool the engine may be used if needed). Set idle
speed not to exceed 920 RPM. (Set for 900 RPM with a tolerance ± 20
RPM.)
(ii) With a laboratory grade analyzer system, sample the exhaust at 40
centimeters depth with a flow sample rate below 320 liters per hour. Allow
sufficient time for this test. Record all HC, CO, NO, CO2, and O2 readings.
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§85.4 §85.4
A chart recorder or electronically stored data may be used to detect the point
of stable readings.
(iii) While operating the candidate analyzer system in a mode which has the same
flow rate as the official test mode, record the levels of HC, CO, NO, CO2,
and O2. Ensure that the probe is installed correctly.
(iv) Repeat step (ii).
(v) Acceptance Criteria: If the difference of the readings between (ii) and (iv)
exceed five percent of the average of (ii) and (iv), repeat (ii), (iii), and (iv);
otherwise average (ii) and (iv) and compare with (iii). If (iii) is within 10
percent of the average of (ii) and (iv), then the equipment meets the dilution
specification.
(d) Analytic Instruments.
(1) General Requirements. The analyzer shall, to the extent possible, maintain accuracy
between gas calibrations taking into account all errors, including noise, repeatability,
drift, linearity, temperature, and barometric pressure.
(2) Two-Point Gas Calibration and Low-Range Audit.
(i) Analyzers shall automatically require a zero gas calibration and a high-range
gas calibration for HC, CO, NO, and CO2. The system shall also use a low-
range gas to check the calibration in the range of vehicle emission standards.
In high volume stations (4000 or more tests per year), analyzers shall be
calibrated within four hours before each test. In low volume stations (below
4000 tests per year), analyzers shall be calibrated within 72 hours before each
test. If the system does not calibrate or is not calibrated, the analyzer shall
lock out from testing until corrective action is taken.
(ii) Gas Calibration and Check Procedure. Gas calibration shall be accomplished
by introducing span gases that meet the requirements of 85.4(d)(2)(iii) into
the calibration port. The pressure in the sample cell shall be the same with
the calibration gas flowing as with the sample flowing during testing. The
analyzer channels shall be adjusted to the center of the allowable tolerance
range as a result of the calibration. The system shall record the gas reading
data from before the adjustment and other data pertinent to control charting
analyzer performance.
(A) Zero the analyzer and perform a leak check.
(B) Calibrate the analyzer using the high-range calibration gas specified in
§85.4(d)(2)(iii).
(C) Introduce the low-range check gas specified in §85.4(d)(2)(iii). If the
low-range check gas readings differ from the label value by more than
±2%, the analyzer shall be locked out from testing.
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§85.4 §85.4
(iii) The following gases shall be used for the 2-point calibration and low-range
audit.
(A) Zero Gas
O2 = 20.7%
HC < 1 ppm THC
CO < 1 ppm
CO2 < 400 ppm
NO < 1 ppm
N2 = Balance 99.99 % pure
(B) Low-Range Audit Gas
HC = 200 ppm propane
CO = 0.5 %
CO2 = 6.0 %
NO =300 ppm
N2 = Balance 99.99 % pure
(C) High-Range Calibration Gas
HC = 3200 ppm propane
CO = 8.0 %
CO2 = 12.0 %
NO = 3000 ppm
N2 = Balance 99.99 % pure
(iv) Traceability. The audit and span gases used for the gas calibration shall be
traceable to National Institute of Standards and Technology (NIST) standards
±1%. Gases shall have a zero blend tolerance. Stations that use large
capacity gas bottles (size B or larger) and that provide a quality control check
to insure proper entry of gas values, may use gases with a blend tolerance of
up to 5%. Gases with a 5% blend tolerance may also be used by any station
if the analyzer system reads the bar-coded calibration gas bottle specifications
and adjusts the calibration accordingly.
(3) Five-Point Calibration Audit.
(i) Analyzers shall automatically require and successfully pass a five point gas
audit for HC, CO, NO, and CO2. For high volume stations, audits shall be
checked monthly. In low volume stations, analyzers shall undergo the audit
procedure every six months.
(ii) Gas Audit Procedure. Calibration auditing shall be accomplished by
introducing audit gas through the probe. The pressure in the sample cell shall
be the same with the audit gas flowing as with the sample flowing during
testing.
(A) Zero the analyzer and perform a leak check.
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§85.4 §85.4
(B) Flow the low range audit gas specified in §85.4(d)(3)(iii) through the
sample probe, ensuring that the tip is equal to ambient barometric
pressure ±0.1 inches Hg (a balloon teed into the gas flow line is an
acceptable pressure indicator; the balloon should stand slightly erect).
(C) When the HC, CO, NO, and CO2 readings have stabilized (no less than
20 seconds of gas flow) record them as well as the PEF value at each
audit blend.
(D) Repeat steps B and C for each audit gas specified in §85.4(d)(3)(iii).
(E) Compare the readings with the audit gas values. Divide the HC reading
by its PEF using the following relationship:
(Reading - Cylinder Value)
Tolerance % = 100* ~ ,. ,—7T~j
Cylinder Value
(F) If the tolerance exceeds ±4.0% for CO, CO2, and HC/PEF, or ±5.0% for
NO, then the analyzer shall fail the gas audit and shall be locked out
from testing until it passes.
(iii) The following gases shall be used for the five-point calibration audit.
(A) Zero Audit Gas
O2 = 20.7% (if O2 span is desired)
HC < O.lppmTHC
CO < 0.5 ppm
CO2 < 1ppm
NO < 0.1 ppm
N2 = Balance 99.99 % pure
(B) Low Range Audit Gas
HC = 200 ppm propane
CO = 0.5 %
CO2 = 6.0 %
NO =300 ppm
N2 = Balance 99.99 % pure
(C) Low-Middle Range Audit Gas
HC = 960 ppm propane
CO = 2.4 %
CO2 = 3.6%
NO = 900 ppm
N2 = Balance 99.99 % pure
(D) High-Middle Range Audit Gas
HC = 1920 ppm propane
CO = 4.8 %
Page 3 7 7/2/96 Quality Control Requirements
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§85.4 §85.4
CO2 = 7.2 %
NO = 1800 ppm
N2 = Balance 99.99 % pure
(E) High Range Audit Gas
HC = 3200 ppm propane
CO = 8.0 %
CO2 = 12.0 %
NO = 3000 ppm
N2 = Balance 99.99 % pure
(iv) Traceability. The gases used for the audit shall be traceable to National
Institute of Standards and Technology (NIST) standards ±1%. Gases shall
have a zero blend tolerance.
(4) Service. Repair and Modification.
(i) Each time an analyzer's emissions measurement system, sensor, or other
related electronic components are repaired or replaced, the calibration audit
required in §85.4(d)(3) shall be performed, at a minimum, prior to returning
the unit to service.
(ii) Each time the sample line integrity is broken, a leak check shall be performed
prior to testing.
(5) Acceptance Testing.
(i) Analyzer accuracy. This test confirms the ability of the candidate instruments
to read various concentrations of gases within the tolerances required by this
specification. The test compares the response of the candidate instrument
with that of standard instruments, and also estimates the uncertainty of the
readings.
The analyzer shall be zeroed and gas calibrated using the high-range
calibration gas. The instrument shall be tested using propane, carbon
monoxide, carbon dioxide, and nitric oxide in nitrogen, with a certified
accuracy of ±1%, in the following concentrations: 0%, 10%, 20%, 30%, 40%,
50%, 60%, 70%, 80%, 90% of full scale for the analyzers. Full scale is
defined in §85.3(c)(3).
(A) Introduce the gases in ascending order of concentrations beginning with
the zero gas. Record the readings of the standard and candidate
instruments to each concentration value.
(B) After the highest concentration has been introduced and recorded,
introduce the same gases to the standard and candidate analyzers in
descending order, including the zero gas. Record the reading of
analyzers to each gas, including negatives (if any).
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§85.4 §85.4
(C) Repeat steps A and B for the candidate only, four more times (total of
five times).
(D) Calculations:
1. Calculate the average value of each concentration for the
readings of the standard instruments.
2. Calculate the mean and standard deviation of each candidate's
readings for each concentration. Include both upscale and
downscale readings for the same gas concentration. (All
calculations may not be possible for zero concentrations.)
3. For each concentration, calculate the difference between the
candidate mean and the standard average.
4. For each concentration, compute the following:
(i) Yi=x + Ksd
(ii) Y2 = x-Ksd
Where
Ksd = std dev * 3.5 for zero and the highest concentration
value
Ksc[ = std dev * 2.5 for all other concentration values
x = mean (arithmetic average) of the set of candidate readings.
5. Compute the uncertainty (U) of the calibration curve for each
concentration as follows:
(i) Ui = concentration value - YI
(ii) U2 = concentration value - Y2
6. Acceptance Criteria:
(a) For each concentration, the differences calculated in Step 3
shall be no greater than the accuracy tolerances specified in
§85.3(c)(3) for each instrument.
(b) For each concentration, the uncertainties, (Ui and U2) shall
be no greater than the accuracy tolerances required in
§85.3(c)(3).
(ii) Analyzer System Repeatability. This test characterizes the ability of the
instrument to give consistent readings when repeatedly sampling the same
gas concentration.
(A) Using an 80% full scale gas, introduce the gas through the calibration
port. Record the readings.
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§85.4 §85.4
(B) Purge with ambient air for at least 30 seconds but no more than 60
seconds.
(C) Repeat steps A and B above four more times.
(D) Repeat steps A, B, and C, introducing the gas through the sample probe.
(E) Acceptance Criteria: The differences between the highest and lowest
readings from both ports shall not exceed the values specified in
§85.3(c)(3)(vi).
(iii) Analyzer System Response Time. This test determines the speed of response
of the candidate instrument when a sample is introduced at the sample probe.
(A) Gas calibrate the candidate instrument per the manufacturer's
instructions.
(B) Using a solenoid valve or equivalent selector system, remotely
introduce an 80% full scale gas to the probe. The gas pressure at the
entrance to the probe shall be equal to room ambient.
(C) Measure the elapsed time required for the instrument display to read
90% and 95% of the final stabilized reading for HC, CO, CO2 and NO.
(Optional: Also, measure the time required for the O2 analyzer to read
0.1% 02). Alternatively the bench outputs may be recorded against a
time base to determine the response time. Record all times in seconds.
(D) Switch the solenoid valve to purge with zero air for at least 40 seconds
but no more than 60 seconds.
(E) Measure the elapsed time required for the NO instrument display to read
10% of the stabilized reading in Step C.
(F) Repeat steps A, B, and C, two more times (total three times).
(G) Acceptance Criteria: The response (drop time for O2 and NO; rise time
for HC, CO, CO2 and NO) times shall meet the requirement specified in
§85.3(c)(2)(x). The response time shall also be within ±1 second of the
nominal response time supplied by the equipment supplier for use in
§85.5(b)(5).
(iv) Analyzer Interference Effects. The following acceptance test procedure shall
be performed at 45_F, 75_F, and 105_F conditions, except as noted.
(A) Zero and span the instrument.
(B) Sample the following gases for at least one minute. Record the
response of each channel to the presence of these gases.
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§85.4 §85.4
1. 16% Carbon Dioxide in Nitrogen.
2. 1600 ppm Hexane in Nitrogen.
3. 10% Carbon Monoxide in Nitrogen.
4. 3000 ppm Nitric Oxide in Nitrogen.
5. 75 ppm Sulfur Dioxide (862) in Nitrogen.
6. 75 ppm Hydrogen Sulfide (H/^S) in Nitrogen.
(C) Water-Saturated Hot Air. Water-saturated hot air shall be drawn
through the probe from the top of a sealed vessel partially filled with
water through which ambient air will be bubbled. The water shall be
maintained at a temperature of!22_F±9_F. This test shall be
performed at only the 75_F, and 105_F conditions.
(D) Acceptance Criteria: The interference effects shall not exceed the limits
specified in §85.3(c)(2)(iii).
(v) Electromagnetic Isolation and Interference. This test shall measure the ability
of the candidate instrument to withstand electromagnetic fields which could
exist in vehicle testing and repair facilities. For all tests described below,
sample "Low-Middle Range Audit Gas" specified in §85.4(d)(3)(iii)(C), at
atmospheric pressure, through the sample probe. Record analyzer reading
during test periods.
(A) Radio Frequency Interference Test.
1. Use a test vehicle with an engine having a high energy ignition
system (or equivalent), a solid core coil wire and a 3/8" air gap.
Leave engine off.
2. Locate the candidate instrument within 5 feet of the ignition coil.
Gas calibrate the candidate instrument.
3. Sample gas specified above. Wait 20 seconds, and record
analyzer readings.
4. Start engine. With the hood open and gas flowing to the
analyzer, cycle the engine from idle through 25 mph on the
dynamometer at ASM loads and record the analyzer readings.
5. Relocate the instrument to within 6 inches of one side of the
vehicle near the engine compartment. Follow procedure
described in step 4 and record analyzer readings.
6. Relocate the instrument to within 6 inches of the other side of the
vehicle near the engine compartment. Follow procedure
described in step 4 and record analyzer readings.
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§85.4 §85.4
7. Acceptance Criteria: The analyzer readings shall deviate no
more than 0.5% full scale.
(B) Induction Field Test. Use a variable speed (commutator type) hand drill
having a plastic housing and rated at 3 amps or more. While the
analyzer is sampling the gas, vary the drill speed from zero to maximum
while moving from the front to the sides of the instrument at various
heights.
Acceptance Criteria: The analyzer readings shall deviate no more than
0.5% full scale.
(C) Line Interference Test. Plug the drill used in part B above into one
outlet of a #16-3 wire extension cord approximately 20 feet long.
Connect the instrument into the other outlet of the extension cord.
Repeat part B above.
Acceptance Criteria: The analyzer readings shall deviate no more than
0.5% full scale.
(D) VHF Band Frequency Interference Test. Locate both a citizens ban
radio (CB), with output equivalent to FCC legal maximum, and a
highway patrol transmitter (or equivalent) within 50 feet of the
instrument. While the analyzer is sampling the gas, press and release
transmit button of the both radios several times.
Acceptance Criteria: The analyzer readings shall deviate no more than
0.5% full scale.
(E) Ambient Conditions Instruments. Upon installation and every six
months thereafter, the performance of the ambient conditions
instruments shall be cross checked against a master weather station.
Acceptance Criteria: The individual instruments shall be within the
tolerance specified in §85.3(c)(4).
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§85.5 §85.5
§85.5 Test Record Information
The following information shall be collected for each test performed (both passing and
failing tests), recorded in electronic form, and made available to EPA upon request.
(a) General Information.
(1) Test Record Number
(2) Inspection station and inspector numbers
(3) Test system number
(4) Dynamometer site
(5) Date of test
(6) Emission test start time and the time final emission scores are determined.
(7) Vehicle identification number
(8) License plate number
(9) Test certificate number
(10) Vehicle model year, make, and type
(11) Number of cylinders or engine displacement
(12) Transmission type
(13) Odometer reading
(14) Type of test performed (i.e., initial test, first retest, or subsequent retest)
(b) Ambient Test Conditions.
(1) Relative humidity (%)
(2) Dry-bulb temperature (_F).
(3) Atmospheric pressure (mm Hg)
(4) NO correction factor
(5) Nominal response time for each instrument (Transport + T90)
(c) ASM Mode or Modes. The following information shall be captured separately for each test
mode (ASM5015 and/or ASM2525) performed.
(1) Final HC running average (AvgHC) (ppm)
(2) Final CO running average (AvgCO) (%)
(3) Final NO running average (AvgNO) (ppm)
(4) Total horsepower used to set the dynamometer (THP5015) (hp)
(5) Engine RPM running average corresponding to the final test score
(6) Dilution correction factor (DCF)
(d) Diagnostic/Quality Assurance Information.
(1) Test time (seconds)
(2) Mode time (seconds)
(3) Vehicle speed (mph) for each second of the test
(4) Engine RPM for each second of the test
(5) Dynamometer load (pounds) for each second of the test
(6) HC concentration (ppm) for each second of the test, not corrected for dilution
(7) CO concentration (%) for each second of the test, not corrected for dilution
(8) NO concentration (ppm) corrected for humidity for each second of the test, not
corrected for dilution
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§85.5 §85.5
(9) CC>2 concentration (%) for each second of the test
(10) 62 concentration (%) for each second of the test (optional)
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