Lidar Standard Operating Procedures


NEIC
EPA-330/9-91-001	;
LIDAR STANDARD OPERATING PROCEDURES
February 1991
National Enforcement Investigations Center, Denver

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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF ENFORCEMENT
EPA-330/9-91-001
LIDAR STANDARD OPERATING PROCEDURES
February 1991
NATIONAL ENFORCEMENT INVESTIGATIONS CENTER
Denver, Colorado

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CONTENTS
LIDAR STANDARD OPERATING PROCEDURES 	 1
FIELD ACTIVITIES	1
OPACITY MEASUREMENT PROCEDURES	2
QUALITY ASSURANCE/QUALITY CONTROL	9
Alternate Method 1 Calibration and Performance
Verification	9
Data Reduction	11
Data Validation	12
Data Reporting	12
TRAINING	12
APPENDICES
A ALTERNATE METHOD 1 TO REFERENCE METHOD 9, 40 CFR 60,
APPENDIX A
B DATA ACQUISITION AND ANALYSIS PROCEDURES
C DATA ANALYSIS REPORT PREPARATION
D OPTICAL SIGNAL GENERATOR CALIBRATION PROCEDURE
FIGURE 1
Ruby Laser Operating Conditions
10

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LIDAR STANDARD OPERATING PROCEDURES
This manual* discusses NEIC standard operating procedures for
conducting lidar investigations of visible emissions from stationary sources
(Alternate Method 1 to Reference Method 9, 40 CFR 60, Appendix A)
[Appendix A],
FIELD ACTIVITIES
Lidar field activities are conducted in t\vo phases, the reconnaissance
inspection and the field measurements. Both phases are usually conducted
off facility property and the facility officials are not notified.
The purpose of the reconnaissance inspection is to obtain information
about the facility (process description, control equipment, operating
schedule, etc.), to find suitable lidar setup locations** and to identify
emission points. EPA regional, state, and/or local agency personnel who
have enforcement responsibility for the facilities proposed for lidar
investigation may be consulted during this inspection. A reconnaissance
inspection may not be required for subsequent measurements from the
same source.
Field measurements are made with the NEIC Omega 1 Lidar. The
hdar system is checked to ensure that it is operational prior to departing for
field measurements. This check includes the laser, telescope-receiver,
processing electronics, and on-board generators. Successfully taking clean
air or reference signals is sufficient to demonstrate the system is
operational.
Visual observations are used to indicate the probability that the
opacity of emissions exceeds the applicable standard, and are the basis for
deciding if lidar measurements should be made. If lidar measurements
* The Lidar Standard Operating Procedures Manual is a supplement to the NEJC
Policies and Procedures Manual.
** A suitable itdar setup location provides a clear line of sight and is usually between
300 and 2,000 meter from the emission point

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indicate that the opacity is below the applicable standard, subsequent
measurements may not be necessary. A facility should be investigated
during all four quarters of the day for at least 3 days or until lidar
measurements show that the opacity exceeds the limit on two separate
occasions.
Sets of measurements (data runs) are normally made over a 1-hour
period, because most regulations are stated in terms of 1-hour periods. If a
state regulation specifies an observation period other than 1 hour (e g ,
30 minutes), the data run should cover the specified period. If a data run
indicates the opacity standard has been exceeded, additional data runs
should be made.
Computer program instructions for taking and analyzing lidar data
are included in Appendix B and data analysis report preparation
procedures are included in Appendix C.
OPACITY MEASUREMENT PROCEDURES
Opacity measurement procedures for the NEIC Omega 1 Lidar are
presented in this section. These include positioning and aiming
requirements, preliminary adjustments and measurements, reference and
plume measurement procedures logbook entries, and operating
restrictions.
A. Positioning and Aiming Lidar
1. When there is a detached steam (condensed water vapor)
plume or a plume with no steam
a. The lidar is positioned with the line of sight from the
lidar to the plume as nearly perpendicular to the plume
as possible.
b. The laser i3 aimed into the densest part of the plume. If
a detached steam plume is present, the laser is aimed

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3
into the plume clearly above the emissions outlet and
below the condensed water vapor.
c.	The laser line of sight must be free of interference from
other plumes or obstructions for at least 50 meters before
and beyond the plume being measured.
d.	There must be at least 50 meters between the point
where the telescope field of view completely overlaps the
laser beam and the plume being measured.
2. When there is an attached steam plume
a.	The lidar is positioned with the line of sight from the
lidar to the plume as nearly perpendicular to the plume
as possible.
b.	The laser is aimed into the densest part of the residual
plume (the plume downstream from the point where all
water has evaporated).
c.	The laser line of sight must be free of interference from
other plumes or obstructions for at least 50 meters before
and beyond the residual plume being measured.
d.	There must be at least 50 meters between the point
where the telescope field of view completely overlaps the
laser beam and the residual plume being measured.
e.	If measurements of 100% opacity are made, the laser
shall be checked to ensure that it is aimed into the
residual plume.
f.	If the azimuth angle correction is being made while
taking measurements, the distance from the stack to the
measurement point is calculated for each

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¦4
measurement. This distance should be used as an aid to
ensure that measurements are being taken in the
residual plume.
g. Photographs of the plume may be taken to document the
point in the plume where all water has evaporated.
3. Additional requirements
a The diameter of the laser beam at the measurement
point within the plume must be less than three-fourths
the plume diameter.
b. Measurements cannot be made when the sun is in the
field of view of the detector.
B Preliminary Adjustments and Measurements
1.	Elevation angle zero adjustment
The channel one zero adjustment on the A/D converter must be
adjusted so that the computer reads zero elevation angle when
the laser is level. First, the mount is adjusted so the laser is
level as indicated by the spirit level. Next, the zero adjust
potentiometer on the A/D converter is adjusted until the
computer readout is zero. The potentiometer adjustment is
normally made during the routine verification.
2.	Tq signal measurement
The time between system trigger and when the laser fires (T0),
and the stack distance must be determined. The program used
to take data (OMEGA 90 program, Appendix B) has a T0
routine for determining both T0 and stack distance.

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The laser is aimed at the top of the stack or just above the stack
lip in the plume. A piece of paper or cardboard 13 held in front
of the laser so that part of the laser beam is scattered into the
telescope and part of the beam is transmitted as usual. The
laser is fired and the return on the oscilloscope is examined to
verify that there is a spike corresponding to T0 and one
corresponding to the stack. The return is then entered into the
computer. The file number is noted in the logbook. T0 and the
stack distance are determined by executing the T0 routine. T0,
the stack time, and the stack distance are displayed on the
computer monitor. The stack distance is also recorded in the
logbook.
3. Signal level adjustment
With the laser aimed through the plume at the densest point
(the point of measurement), the photomultiplier tube voltage
gain is adjusted so that signal level before the plume is at least
one-third full scale. The gate generators may be used to
eliminate signal distortion which can occur immediately after
convergence and/or the plume portion of the backscatter
signal. One gate is adjusted to suppress the close-in, off-scale
return after convergence. The other gate is adjusted to
suppress the large return signal from the plume.
Reference and Plume Signals
1. Reference signals
Before making plume measurements, the laser is aimed and
fired with the line of sight near the plume height and rotated
horizontally to a position clear of the source structure and the
plume. This backscatter signal is the ambient air or reference
signal.

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6
a.	Signal quality requirements
The reference signal must be inspected to. (1) determine
if the lidar line of sight is free of interference from other
plumes and from physical obstructions for a minimum
of 50 meters before and beyond the plume, and (2) obtain
a qualitative measure of the homogeneity of the ambient
air by noting any signal spikes. If there is not a mini-
mum of 50 meters free of spikes both before and beyond
the plume, the laser is fired three more times. If the
spike disappears in all three reference signals, and
there is no interference from other plumes, the signal
quality is acceptable. If the spikes remain, the azimuth
angle is changed and the above procedures repeated.
b.	Shot-to-shot consistency
Shot-to-shot consistency of a series of reference signals
over a period of 20 seconds is verified in either of two
ways: (1) If the ratio of the signal amplitude in the far
region to the signal amplitude in the near region varies
by no more than ± 6% from shot-to-shot, the series of
signals is consistent, or (2) treating one of the signals as
a reference signal and the remainder as plume signals,
the signals are consistent if the calculated opacities are
within ± 3% of 0% and the standard deviation (S0) values
are less than 8%.
c.	Time requirements
Three reference signals meeting the requirements of (a)
and (b) above must be recorded within 90 seconds before
any data run. A final set of three reference signals
meeting the requirements of (a) and (b) must be obtained
within 3 minutes after the completion of a data run.

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If, during a data run, the near or far region standard
deviation increases more than 6% from the previous
plume signal and this increase remains for 30 seconds
or longer, or the plume direction changes by more than
30°, a new set of reference signals must be obtained. If
measurements are corrected for the azimuth angle, the
lidar computer will display the message "SIN, SIF is 6%
bigger for 30 seconds, "or "drift angle has changed by
30°," to alert the lidar operator when either of the above
changes occur. However, if measurements are
corrected for elevation angle, the lidar computer will
display the message "SIN, SIF is 6% bigger for
30 seconds" when the standard deviation increase
requires additional reference signals and the lidar crew
must visually determine if the plume direction changes
by more than 30°.
An additional set of reference signals shall also be
obtained if there is a change in amplitude in either the
near or far region of the plume signal that results in
excessive signal spikes and negative opacity values, and
this change in amplitude remains for 30 seconds or
more. The lidar operator will determine when these
changes in amplitude occur by observing the opacity
values reported by the lidar computer.
2. Plume signals
Once the reference signals are recorded, the lidar is aimed at
the plume as specified in Section A and plume signals are
taken. The lidar is fired at approximately six pulses per
minute (1 shot/10 seconds). The length of a data run depends
on the applicable regulation and the source.
For continuous sources, a data run should be at least
15 minutes long. If the applicable regulation specifies an

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opacity limit for a maximum aggregate period in 1 hour, then
a data run should be 1 hour. For intermittent sources, the
lidar is aimed at a proper spot for good reference signals.
When intermittent source starts emitting, a set of reference
signals is quickly obtained and the plume signals started as
soon as possible.
D. Logbook Entries
The following information is recorded in the lidar (blue cover)
logbook. A lidar logbook is used to record information on only one facility.
1.
Facility name and location
2.
Date and time (begin and end) on location
3.
Source identification
4.
Lidar location
5.
Direction to source
6.
Range to source*
7.
Laser elevation angle*
8.
Plume characteristics (color, shape, steam, etc.)
9.
Approximate wind speed and direction (at the lidar)
10.
Air temperature and relative humidity**
11.
Estimated cloud cover**
12.
Computer data run file numbers
13.
Start and stop file numbers and times for:
* The range to the source and the lidar elevation angle are obtained automatically
from the lidar computer.
** Data taken at beginning and end of lidar field activities.

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9
•	Routine verification
•	T0 signal
•	Reference signals
•	Plume signals
14. Opacity measurements for the routine verification
15 Operator's and safety observer s signatures
E. Operating Restrictions
The lidar will not be operated in rain or snow. Laser light reflected
from raindrops or snowflakes can present an'eye safety hazard in the area
of the lidar.
The lidar cannot be operated when it presents a danger to aircraft.
The appropriate FAA chart should be used to determine whether airports or
air traffic would preclude lidar operation. Lidar operation will be
interrupted whenever the laser line-of-sight is approached by aircraft.
When the dewpoint temperature is above 22 °C, drops of water may
condense on the ends of the laser rod. This could cause laser energy to be
focused at a point inside the laser rod, resulting in permanent damage.
Figure 1 shows a plot of relative humidity as a function of Fahrenheit
temperature for a dewpoint temperature of 22 °C. It is prudent to operate the
lidar when the temperature and relative humidity are below the line.
Operating when the temperature and relative humidity is above the line may
result in damage to the laser rod.
QUALITY ASSURANCE/QUALITY CONTROL
Alternate Method 1 Calibration and Performance Verification
Alternate Method 1 specifies two methods for verifying the proper
performance of the lidar equipment - annual calibration and routine
verification.

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80
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TEMPERATURE



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40
70
75
80
05
TEMPERATURE
90
95
100
Figure 1
RUBY LASER OPERATING CONDITIONS

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11
The annual calibration is conducted using five screens with nominal
opacities of 10, 20, 40, 60, and 80%. Each screen is measured for 15 minutes
using the same procedures that are used for measuring smoke plumes.
Also, a 15-minute series of measurements of ambient air is made. One
calibration series annually is required.
Routine verification is performed before and after a series of data
runs at a facility, or every 4 hours when the senes of data runs lasts longer
than 4 hours. Routine verification is done using an optical signal generator
which produces simulated lidar backscatter signals with nominal opacities
of 0, 10, 20, 40, 60, and 80% which are measured by the lidar receiver. These
simulated signals are processed exactly the same way as actual plume
signals. The calibrated opacity values for the optical signal generator are
determined monthly while the lidar is in service, using the procedures
described in Appendix D.
If the opacity, measured by the lidar, differs from the calibrated
standard by more than 3% during either the annual calibration or the
routine verification, a malfunction exists which must be corrected, and the
lidar must successfully complete the failed test before measurements can
be made.
Data Reduction
Lidar data is reduced on the Micro-Vax II computer using
OMEGA 5, the NEIC lidar data analysis program [Appendix B]. The
program selects pick points automatically using criteria specified in
Alternate Method 1. The operator verifies that the pick point selection is
correct, and that the plume signal is acceptable.
To be correct, pick points cannot be selected in plume signal low
points which are caused by overcompensation of signal amptitude following
the plume signal or signal spikes. If the pick point selection is not correct,
a new pick point selection is made. Up to six additional pick point
selections may be made to obtain a correct selection, before a plume signal
is rejected.

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12
A plume signal is acceptable if: (1) there is sufficient distance in the
near and far regions that is free of signal spikes to accommodate pick
intervals, (2) the plume width remains relatively constant (about ±1 plume
width) from signal to signal, and (3) the standard deviation (S0) is 8% or
less
Data Validation
Lidar data will be analyzed and compared to a regulatory limit based
on an average opacity value and/or an aggregate time limit for a specific
opacity. For average opacity data, if the highest 6-minute average exceeds
the regulatory limit by less than 10% (full scale), the data will be validated
by a second operator. For aggregate data, if the length of time the opacity
exceeds the regulatory limit is exceeded by less than 10%, the data will be
validated by a second operator.
Data Reporting
Analyzed lidar data is converted to plots and tables using NEIC
computer programs OMEGA 7 and OMEGA 8 [Appendix B], OMEGA 7 is
used to report averaged data and OMEGA 8 is used to report aggregate
data.
TRAINING
All lidar operators must attend a course on laser safety and
successfully complete a course on lidar operations. The laser safety course
is a classroom presentation covering laser physics, nature of light, optics,
effect of laser radiation on eyes and skin tissue, laser eye safe distance, and
safety precautions for working with high-voltage equipment. This course is
given to new operators before taking the lidar operation course.
The lidar operation course includes a classroom presentation and
hands-on training. The classroom presentation covers basic lidar
principles, the function of major lidar components, and an explanation of
the NEIC Omega 1 Lidar components. The hands-on training is a

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13
three-phase program conducted in the Omega 1 Lidar. In phase 1, the
operators are given operational and maintenance instructions for all major
lidar components. On-site field activities are also explained including
filling out logbooks and how to operate the data acquisition program
(OMEGA 90). In Phase 2, the operators take lidar measurements. All
steps required to take data are performed by the operators. In phase 3,
operators are certified by demonstrating correct procedures while
measuring the opacity of a known standard. To remain current, operators
must be certified annually.
Laser safety training is not included in the annual operator
certification but may be repeated for operators who have not certified for
3 years.
Records of laser safety, operator training, and operator certification
are maintained by the Health and Safety Officer.

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APPENDICES
A ALTERNATE METHOD 1 TO REFERENCE METHOD 9, 40 CFR 60,
APPENDIX A
B DATA ACQUISITION AND ANALYSIS PROCEDURES
C DATA ANALYSIS REPORT PREPARATION
D OPTICAL SIGNAL GENERATOR CALIBRATION PROCEDURE

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APPENDIX A
ALTERNATE METHOD 1 TO REFERENCE METHOD 9. 40 CFR 60,
APPENDIX A

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Title *0— Protection o~ 8nvironm#nt
ALTtnnATt Mrrwoa -arrtm<[ii*rtoi« or
:hx Op*ctTT or E^un-oss F*o* Staiiok-
 The method includes procedures
tor trie caliorauon of ".he 'idar and proce-
dures to oe used in :t"e field lor trie iidar de-
'ermination of alume opacity The hdar is
jjed 10 measure ;tume opacity during
eitner aay or mgnu.me nours Because it
contains its own pulsed lifnc source or
'.ransmitter The operation of the lldar is
noi dependent upon ambient lighting eondl-
'joruiiiinc darn, sunny or cloudy)
The iidar mechanism or tecnnique is ap-
siicaaie to measunrg plume opacity tt nu-
merous »aveiengins at laser radiation. How-
eve r :.-.e aerformarce evaluation and call-
ontion test reiuiu given in support of cnis
T.etnod apply only to a Iidar that employs a
ruoy ired ugnt) laMr (Reference i IJ.
I. Pnncipia and JppttcaMflfv
1.1 Principle. The opacity of visible emu-
lions (rom stationary source* > nicu. roof
nam etc.) is measured remotely by a
mottle iidar (later raoari
l.J AppUeaeility This met nod is applica-
nt* for trie rimou measurement of in*
opacity of visible emissions from sutionarr
source* during both nighttime and daylight
condition*, pursuant w 40 C7R I 50.11(61 U
s i.so I3iuca3ie 'or -,e .i.-ori. on ira
;e''3r—arce e- ' en.or :! -e -iobi e c:ar
'-r "t -euu-f-fn-. jf -e jeic i! *11
: orj * ;e-':r— a.-.ce cesin >sec • ca. on
';r i 315lc is.r s>s.,e — s i.io ncor;c-a.ed
-•.o - j —,e'-ao
I 3 De'-n;: oris
U'.T'in i.-ge Twe i-j'e p -cr :o-i
i.i ; ar,e -it itsijr.v.n knc! -e i^er
3earn s ;cir:ed !' s -neisurea '•on ar ir
3' -a.-> ' te-fl -e'ererce re n -nat ::art
3acne 'idsx hneofjignt
Beyond or oenind '.ne plume oeing mev>-
ured
L.dat Acronym for L;ghi Detection arid
Ranging
I_dar range The range or distance (rom
the lidar to a point of .nterest along :he
:idar ime-of sight
^eat region The region of the atmospner
,c oain along ir.e hoar ur.e-oi jigrn setwetn
the hdars convergence distance ana the
plume oeing measured.
Opacity One minus the optical transmit
cance of a smote plume screen target etc
Pick interval The time or range interns
n the ltdar sacucatter signal vhose m.ni
mum average unoiituoe is used to calculate
opacity Two pic* intervals are required sne
in tne near region and one in the far 'egion
Plume The plume oeing measured oy
lldar
Plume signal The iacocatur signal re
juiting from tne laser light pulse owing
tnrougn a oiume
11 R* correction The correction made for
the systematic decrease in iidar oacucatter
signal amplitude «un range
Reference signal. The oacucatter signal
resulting from tne later mm pulM paasing
through ameienc air
Samole interval The time period aetween
succetaive samples for a digital signal or D«-
iwe«n iucceaaive meaiurementa for an
uiaiog signal.
Signal spike An aorupt. momentary in-
crease and decrease in signal amplitude
Source The source being tested by Iidar
Time reference The time (t.i -Khen me
laser pulae emerges (rom the laaer. used as

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Chapter I—Environmental Protection Afltnry
Port 60, App. A
~e reference -n all dar "-le or range
"¦easuremenu
P-tenure)
"^¦•e -rooile '.idar catioritea n accordance
-ith ParifTipn 2 of - s -^ei-oa snail -se
he foils*ing procedures .or -enotely -neas-
>ring tne opacity ol stat.orary source emu-
jions
2 1 Lidar Position T^e dir snail ae po-
sitioned at 4 distance -om -he owme sulfl
cent to provide an unoosiructed new ol trie
source emissions 7ve jn-me must se it a
-ange of at least JO meters or three consecu-
tive pics intervals .micnever is greater)
'rorn the lidars transmitters receiver con-
vergence distance aior.i .ne nne-of signt
T^e -naJtunum effective opacity measure-
ment distance of tne ' sar s a function of
.ocai stmospnenc conaicoru laser seta di-
ameter and piume aianieier The test poai-
* on ol the Udar snail :* jeitctec so tnat me
diameter ol me laser seam at tne measure-
ment point within trie siume snail Be no
arger -.nan three (ouiim .ae slums diame-
er The beam diameter j calculated ay
Equation (AMI-.;
DiUdari-A-RocO 73 D(Plume) (AM1-1)
where
D(Plume>"dlameter of r"e plume (cm)
i-laser beam divergence "neasured in ra-
diant
R-range from the !:dar :o the sourer ioni
D'Lldar)-diameter at trie laser Beta at
rant* R (em)
A-diameter ot 'he laser beam or pulte
where it leaves the uer
The tidar range R .j obtained By aiming
and firing the laser at -r.e emissions source
structure immediately selow the outlet The
range value is then determined from the
sackscatter signal wmcn consists ol a signal
spike (return from souree structurei and the
stmospneric sacMcatter signal [Reference
S This bacucatter signal ineuld be re-
corded.
When there Li more than one source of
emission* in the u&medlau vicinity of the
plume. tne iidar ah ail be positioned » thai
'.ne laier beam aum tnrough only a single
3iums free froo any interference of the
other plusta for a ¦"»"«"¦» of 50 meter* or
three consecutive pick internals .i whichever
is muiri la each region before and beyond
UM plum* along the luie-of tight (deter-
rubM from the Bacucatter signals) The
Udar shall initially be positioned so thai u
lira ol-tight u approximately perpendicular
to the plums.
When measuring the opacity of emissions
from rectangular outlets teg., roof mom-
ton. open bagnousa*. noncireular iiacu
etc.). the Udar shall be placed in a poaiuon
so thai iu Une-of etgnt is approaunatsly
perpendicular to the longer (major) mi of
tne outlet.
2 2 Udar Operational Kestr'ct.orj 7ke
lidar receiver ina.J not se aimed ntnji in
angle of r 13' icone anglej of :ne sun
T *.i3 method shall not be used to naite
opacity measurements it 'hurderstormi
snowstormj. Jiail stormi, nigh uno -,ign
amoient duit leveLs log or other aimojpner
'c condition# cauM tne reference sigr.als .o
:onsuientlK exceed the Ijuu specified r.
Section 2 1
21 Reference Signal Refluiremenu
Once placed m iu proper poiition (or opac-
ity meaiurement the laser u aimed and
fired *ith tne iine-o( tignt near the outlet
height and rotated horizontally to a poei-
tion clear of the source structure and the
aaiociairt plume The bacucatter signal ob-
tained from thii poeition u called the ambi-
ent air or reference signal The lidar opera-
tor shall inspect tru» signal (Section v ol
Reference i I] to c U detemire if tne naar
line-of-signt u free from interference from
otner piumea and (r«m onyaicai ooatruc
ttons sucn u cablev power line*, etc .'or a
minimum ot 30 meters or three coiuecuute
picK interval! (whichever u gTeateri in eacn
region before and beyond the plume and (2)
obtain a qualitative meature of the r.omo-
genetty o( the ambient air by noting any
signal spite*
Should there be any signal spiket on the
reference ugnal whin a minimum st 50
meters or three consecutive pica intervals
(wmenever u greater) tn each rrgion before
and beyond the oiurae. the luer shall be
fired three more time* and tne operator
shall inspect the reference signals on tne
dlsptay [f the jpilte remains, the aumum
uigle shall be changed and the above proce-
dures conducted again If the spikef there is shot to-
shot consistency and there ls no interfer
ence from otner plume*.
ghot-to-anet consistency of a sene* of ref-
erence signals over a period of twenty sec-
onds is verified in either of two ways, il)
The Udar operator shall observe tne refer-
ence signal amplitudes. For shot-to-snot
consistency the ratio of R, to R. i ampli-
tude* of (he near and far region pick inter-
vals (Section IS 1)1 snail vary or not more
than ? between shots, or (3) the Udar
operator snail accept any one of the refer
ence signals and treat the otner two as
plume signals, then tne opacity for eacn of
the subsequent reference signals ts calculat-
ed (Equation AM1-2) For snot-to-ehot con-
sistency. the opacity value* shall be within
s 3% of 0% opacity and the associated 3.
value* lew than or equal to 3% (full scale)
(Section s.t).
If a set of reference signals falls to meet
the requirements of this section, then all
plu&e -i—t cSaction 2 ti irom the last set

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Part 40. A op. A
Titl* 40— Protection of Environment
3f lcceoiiole -e'e^-ce - r~& 3 3 ~t 1. ed
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Re'erence signns 11; . c-a, jet 3; -ef
s-fce s.gniu jr.j.i oe z- a.rea --ir " * a
:a:a run ,f '."ere 1 1 c-jrie • i:s: *rs
on or siume an!-. JO ~r — ore "on
:.rection -pat *as pre^aie^t *nen "~e ast
>et of reference signals tis outlined An id
a tional set of refererce si*rais snail alio ae
ootuned f there s in -csiie n • 11 ae o(
S> near region stancara :ei:aoon Equa
¦	on AMI-5) or 5 . 'ir -e?'ori uir.dara sevi
at on Equation AMl-o1 '".at s greater mm
¦j"; 'utl scite> o".er --e -•ioec,r e Hues
calculated '-on '-e ~i.Tea'acelv srevious
siume signal ina ~.,i -ic-?is« ti 'Hjc re
-lias ;or 30 secanas or orei ot -efe'ence l.inais >"»H ilia oe oo-
ainea if '"ere 3 1 c-irge - imsiit'jae in
¦e't.ier *ie ietr or -e rar -;gion of :ne
siume sigr.il .nat s greater ,*an of tne
r.ear signal amsr.t.ae ma tj cunge ti
amplitude -emains 'or JO secar.as or -nore
2 4 ?'ume iignai Recui.-ements Once
properly aimed :.-.e dar s Sliced n ooer
at.on iit,"1 tie °or-.inai suiie or firing rate
of i x juuev rrutVA'.t '» 51.if '.0
The ndar oserator snail oosen-e Tie siume
:*c*.icitter v«ni3 '.0 aeier-nine '.~e need
'or iaau:oraJ -efe-ence signau u required
sy Secuan 2 3 2 T^.e siume s gr-.aa ire re-
toraea ':om iidir start :a stop ana ire
called a aata rjn T^e eigtn of a data run
s aetermr.ea Sy operator aucretion Short-
term uodj of .'te ,iaar to record iddmonai
reference signau do noi conmtuie tne end
of a data r-jn if plume signau are rejume
jr OK . g-t e\.n T*' >en
the jvater vapor n a hydrated plume car.
aersei ird Become* '.isicie at a r 1 nice nu
'ance from the stack or source eniuioni
outlet the opacity of the emissions snail :e
T.easured in tne region of tre plume -'early
aoovr the emuiioni outlet ana aelow con
sensation of the water vapor
Durtng daylight hours tne lidar operators
can visually determine if the steam plume s
detacned from the stack outlet Durirg
-ugnttime noun a hign-interuity spothgnt
n-gnt vtjion scope low iignt level TV etc
can se used as an aid in determining if tne
stea/n plume is detacned It MsuaJ determi
nation u ineffective tne Udar may oe used
to determine if the steam plume is detacned
ty repeaiMly "neaaurtng plume apacity
Tram tht autlei to in* steam ciurne along
the plume* lonptudLnal axis or center Mne
T^e lidar operator should also ooaerve color
difference* ana plume reflectivity to detect
a detacned plum*. If the operator does not
oBtain a clear indication of the location of
the detacned plum*, thu method shall not
ae usM to make opacity meaaurements oe-
tween tne ouUet and tne detacned plume
One* the determination of a detached
iteafli slum* ha* Men confirmed, tne laser
shall be aimed into tne reron of hignest
opacity in the plume o*t«een tne outlet ana

-------
Chester I—Environmental Protection Agency
Pert 60. A pp. A
¦¦e (ormiuan of -Ke 3r;ir siurre *:rrim
^dj-jtmntj snail ue T.jae 'o "e air i
-t 01 sijm iurv-. \t 3iume ro corrfct :or
i-;«s " ~e ocition ji "• ~.ost sense
-jico- ;i -e 3iuni« due '3 cra.-ge* i"id
rK' on ird sceed or if 'he ^e'acred Jteam
T.o^ts closer .o i.k «r\.Te ou"t' »n
-oacnini on -ne —osi ae^je --?'cn ;( He
3ljme If the detacrea steam aiurre snould
-love coo clow lo :ne scurre outlet 'or '.ne
.aw to tike interference tree ooacity
^e«jurement» :nu -netr.oa snail -iot oe
jjea
: J Field Records Jn addition to •-."e re-
orcinff recommenaal.aru rsted n oiner
ject onJ of '..Tu metnoa :n< following re-
cords should oe maintained Eacn jiurne
-leasured should oe uniquely 'dem.iied.
T^e name of the facility . se or faculty
¦"-iijaion source type geograoric location oi
~.e ndar *uh respect to '-e ;iu:ne arid
¦Jiurne characteristics ihouid oe recorded
T^e date of :."e test :ne time oertod -« i
source «u monitored. the ".me uo me -r%r
;sl vewndi o{ each ocacny meaiurt-ieri
and trie sample interval should alio oe *e
corded The »ind speed vind direct.on air
•enperacure relative lumidity .isioi.ity
measured at :ne iidar i sositiom and c.oud
:o>.er mould be recorded al the aetihr.Lig
ir.d end ot eacn time oeriod tor a i.ven
joviree A small sketch aepict'.nj ine ioca
:.or. o( the laser beam within :he slum*
should be reecreert.
•J i detaeriM or attached steam plume n
present at the emotions source tnj 'act
should be recorded. Figures AMl-t sr.a
AMI-II ue example* of lojooon forms mat
nay oe used to recotd this type oi data.
Macnetic tape or paper tape may also oe
.sec to record data.

-------
Ilftta 1*4.	M«IIM
U| ft»*k		
|t|K|* • (MltM mill U •!«! Illililltl MIX! 		I
IMIIfl
•OI4I
titl
IIIUUI
matt
(III ft 1 All




» g.or AMI I 4 t<< I j
ll»k« 11# L 4UW*Ul \4 HfttN It HI I Ulll\
a
a
Claim
••••I*
• All
0
1

-------
" aptar I—
Environmental Protection Agency
fart 60, App.
A

-------
Pan 60. App. A
Trtl» 40—Protection of Environment
,, o.-i «-:• 5 ¦»' C;-'tei»a
N « 4' ^ tg CM
,* ir ** t-g : -

4 4 it
! ! ¦ i
-i
"« :r 'anije
vQi ° ^• 5 5*1*! * C s^ictid
- 3 'u m • 3 0 «•
~ *
>—
I. >4
*i-i« or 3an.ge ——
jj 3j'crtBtj ^ -r
-------
diopter I—Invironmentol Protection Agency
Part 60, App. A
: 9 Opacity Calculation ira Dm vuiy
j Referrng "o .re re'er-nce sijt.u ind
-me ngnu n rv-i"t VMI-III :-e -neas-
¦;a opacity O.j r. percent :or eacn asx
-neasurement u calculated using Eoua: on
AML-2 iO.-l-T„ T, j the piume tjju-
mutance )
0p = (100*)
1 -
I.
(AMI-2)
"¦Mere
.» near region sick TtenaJ s.gnal ampn
:ude piume signal 1 R corrected
.min region pick ncer^ai signal amplitude
plume signal. 1 R':or-ee:ed
-new region pick n-.erai signal ampil-
'.udt reference signal i R' corrected
and
a- = far region pick -r.enii signal imou
•ude reference signal 1 R1 corrected
Tve l.-R" correction :o c.-.e plume in a ref-
"•nre signal jmouiudei :s maae ay mum-
;.>ing im amplitude lor jacn successive
^impie interval from tne t,me reference ay
rie square of '.fie lidar time - or range; um-
: ited with that survate rvt.sr.-ai tRetecetwe
1 I).
The first step in selecting the pick inter
all for Satiation AML-2 .i :o divide me
piume signal amplitude By ;he reference
signal amplitude at trie same respective
•angei io ootarn a norrnaiued signal The
pic* intervals selected using this normaliied
signal, are a minimum of 13 m 1100 nanoie-
condii m length ana consist of ai least 5
-oniiguouj sample interval! In addition,
he following criteria. listed in order of im-
portance. govern pick interval selection. (I)
The interval shall be in a region of the nor-
malized signal where the reference signal
meeta tne requirement* of Section 2 3 and u
everywnere greater man »ere. (1) The inter-
nal* (near and 1 ax> nun tne minimum aver-
age amplitude art cnoaen <1)1/ mora than
one interval with the same minimum aver-
age amplitude u found, tne interval cioaeat
to the plume u cboeen. it) The standard de-
viation S. lor the calculated opacity mall
be t% or leaa- IS, la calculated by Equation
AK1-T).
Ul.li greater than »<"« then the far pick
inur**l shall be chanted to the nest inter-
val of minimal average amplitude II S. u
still greater than 8*.. then this procedure j
repeated for the far pick interval Thu oro-
ceaure may Be repeated once warn for -lt
near pick interval but if 3. remains greater
t.Kan t", the plume signal shall Be discard
ed
The reference signal pick iniervaii R. ana
R. must be chosen over the same urae inter
al as the plume signal pick intervals 4,-a
I, respectively [Figure AM1-III] C trier
-netnoda of selecting pick intervals may se
used it they give equivalent resuiu fieia-
oriented example* of stele interval selection
are available in Reference S 1
The average amplitudes for each of "-r
pick intervals. I., L. R„ R„ shall be catcum
ed by averaging the respective individual
amplitude* of the sample intervals from :ne
plume signal and the associated reference
signal each corrected for 1*R' The ampn
:uae of I. shall be calculated according :o
Equation (AM-))
I « * XI
n ¦ ,* ni (AM1-3)
where1
t„-the amplitude of the ith sample interval
(near region),
latum of the individual amplitude* for the
sample interval*,
m-numoer of sample intervale in the pica
interval, and
I.»average amplitude al the near-region
pick interval.
Similarly, the amplitude* for t>. R.. and R.
are calculated with the three expmiion* in
Equation (AMl-4).
-------
TitU *0—Pfeteclien «t Environment
Twf stiraara i:.on 5. of -."ie is: j(
ns1 J-- "t -eif region 3ic* .menu
]-iu ;« caicjinea mm# Equation
AMl-Jp

a
! i
i i*i
! r
( !»• L)
(AMl-S)
Similar1/ *-ne jtuiuu-d dnn»tioru S„ 5...
and 5., ire eiicjutea »un iti# mr« expres-
sions m £qu*(1°n
C-n- LI
fl
I
1*1
( ' * * >'

fl
I
1*1
t ^ - I!
¦ < I

-------
apttf |—|nvironm«niol Protection Agency
Part 60, App. A
."^le staneara aevat or £, ';r *ich iisociatea opacity . Hue 0. jmll Be calculated „sir,g
..uat>on 1 WIL-7)
(AMI-7)
7s.e calculated Mines of 1, R. R. 5..,
S>,. Sv- 0t. and 5, sr.ouid oe recorded
-y piume signal »itn a.i a, treater than
lhaU be discarded
78 1 Uimuth -tngie Correction I: :he
:..Tiuih angle correct.or 3 ioacity speci-
»<3 in 'his lection s ;e''or-nea men tne
elation ingle correct cn specined in 5ec
on 5 6 2 snaJl not oe periormed When
sacuy is measured in the re»iduai region of
- t tacr.ea steam siume ma t.-e l.dar libe-
lant is not perpenaicj.ar to tne plume 't
-ay oe necessary to correct "he opacity
-eisurec by trie ndar -o cot am tr.e opacity
at would oe measured an a pain serpen-
:.cuiar 'o tne plume T^e 'oilo*mg metnod.
;r any other rreinoa »nicn produces equiv
alent results snail be used to determine tne
need for a correction, to calculate tne cor
-ection. and to document tne point witnm
tne plume at which tne opacity «u meas-
ured
Figure AMl-IV(b) shows the geometry ol
tne opacity correction. L is the path
through the plume along wnicn tne opacity
measurement i made P" n the path perpen-
dicular to tne plume at the same point. The
angle ¦ is tne angle between L and the
plume center line The angle (•/It) is the
angie between tne L and P The measured
opacity 0,. —.easured along the pain L
shall be corrected to obtain the corrected
opacity. 0„. for the path P using Equation
i AM1-8)
Opc = COC%)[l - (1 - 0.01 03)Cos
= COOS) [l-(l-0.010)s,nel (AM1-9)
L p J
Twe correction in Equation iAMl-8) snail be performed if the inequality in Equation
is true
Sin
. l
In (101 - 0p)
In (100 - 0p)
(AM1-9)
Frur* AMl-rV(a) shows the leometry
ua*4 to caleuiau • and the position in the
plum* at wnicn the lidar measurement is
mad*. This analysis assume* that for a
gives ndar measurement. the rang* from
the Udar to the plume the elevation angle
of the Udar from the horizontal plan*, and
the uimuih angle of the iidar from an arbi-
trary fixed reference in tne horizontal plane
can all b* obtained directly
-------
V ill i 11 4iiyte i 1 ton
P IH i* # u', a )
4 4 ' *d
lt4*r fovilMM
a
3
s
~
f
i id^r I mr ot b i«jht,
Covu^ P
i*>\
Project mn ut P i>«Hw I fir «y
f iyure AMI IV Cuireiliui* in Gp^tity lot Offft t*f li»*
N*yliJu«l Hcyiuji of 411 Atlaihril SI CAM PluAC
-------
Chaptar t->Environmental ProtvcHon Aganry
Parr 60. App, A
R,-rarce from naar a source"
J.»eJ«vit:on ir.g.s o1
R,-»rtnge !rom jar o :'jme »t :ne opac-
[y Tipuurf^M1. :onr
reiation »r.» e oi R,'
R,*-a.-.ge rem oir 3 o jrne at jome aroi
-ir> ;omt P, jo -e srft irsgie of :ne
iiume can se at'f~--.ta'
J, >elevation ir.gie oi R."
; - ingie seta een R, ira R,
R , » oro'ection ol R, n ere noricmj :.i
R , - pr3iect\or\ of R, n ' r.e -or sor'.u 2 a^e
R . = projection of R, n :*e -or jorv.ij ;.aj*e
v -angle oei»een R , ina R
3 - angle 9et*een R , ma R ,*
RS »aistaree Tom '.ne source '0 ,-t ;aac
ity neajurement point 3ro,ec-.ea .1 -e
f.or.zamai oitne
RJ"diitanee 'ram opac/.y neuurtment
point P. to tne 301m n "ie siune P,
PC
- C - 0a)
Co» (n/2-c)
1 - (1 - 0 )S,n £
3 (AMI-9)
T7ie correction a.-gie 1 sniil Se determined
using Eauation AMI-ID
inere
3 ¦ Cos* 'CojJ, CcjJ. Coia-SinJ, Sirui.J,
ana
RJ»' 1
RS the dUlWice (rem tr.a soiuce to -.ne
opacity measurement point projected in the
hortioniai plane. inali 6e aetertnined aiuig
Eauanon ami- 11
C*;«
R'»
Q
2IT IT Cos
130* th# tamutn angle correction than not
-« p«rforrn«4 and tftt aaaaoaud opaatj
' tiut inau S« dimroad.
1S 2 Elevation Angle Correction An in-
dividual lidar-meaiured opacity O.. jnaJI D«
comcud for elevation angle if the laaar ei«-
vauon or inclination and*. J, [Fi«ur« AMI-
V], J crwur tnan or aauai to tne valua eai-
culattd m Jtquation AM1-13
-------
Part 60. A pp. A Titlo 40— Protection of Environment
f l.i CCl - OJ 1
I J 1
I ,r, (-CO * Op) J (AMI - II)
3 > Cos
-I —
"Pie neaiurefl ooaciy Ot. ilong •*« "dar sith L. 1* adju*t«d to olicam :tie correc'.ea
opacity O. .'or :ne ic-.uil jlume mornontia) pain. P by ujlb< Equation (AM1-14)
3C
IOCS) 1 - (1 - 0.01
yeo"»
]¦
(AMI-14)
»h»w
3,-lid*f elevation or inclination angle.
0.-me*»uf« opacity aionj patn L and
O.-coirteted opacity for tne actual glum*
tfticfcitcu P
Tha vaiuM for Q, and Q. should a* re-
corded.
-------
Chapter I—Environmental Protection Agency
Part 60. App. A
i
-------
Part 60. App. A
nt1» 40 ¦ Pfotacliow at lnvironm«n1
2 9.3 Determination of \ctual Pume
Opacity Actual op«£iiy of ilie stume in ill
se determined ay Equation AMI-IS
d«
= 0
pc
:s s.
' 5*]
(AMI-IS)
I J 4 Calculation of Average Actual
P'ume Opacity The average of ;Me actual
;lume opacity. S. inaii be calculated u
the ivera** at the cafjecu'j.ve \noividual
actual opacity value*. Sm. ay Equation
AM1-1S.
5» * i ix (v«
(AMI-16)
wner*
<0„),»che kth actual opacity iaiue in an
averaging interval containing n opacity
. alues ink summing index
:>.ne sum of the individual actual opacity
values.
p.atne number of individual actual opacity
value* conuuied in me averaging uit*r-
_ vaL
0„«*ver*g* actual opacity calculated over
r.he averaging interval.
3 Lldar Performance Verification. The
lldar shall be lublected to two types o( per-
formance verifications that shall be p*>
formed in (he Meld. The annual calibration,
conducted at least once t year snail be used
to directly verify ooeration uid perform-
ance of the enure lldar system. The routine
verification. conducted for each emission
source measured. shall b« used to insure
proper performance of cne optical receiver
and usoeiated electrontca.
31 Annual Calibration Procadurea.
Either a plume from a smoke lenerator or
screen targets shall be used to conduct thla
csiibratioa
the screen target method is selected,
fi^e screens shall be fabrtcaud by placing
an apaqu* metft raaurtal over a nam*
(rtat (wood, metal extrusion, etc.). The
ma ittU han a surface am ot at least
see square never. The ktwii material
sbnM be chown for precise optical opaa-
\tm ot about 10. ». 40. M. and «0*. Owe-
ity ot eaeft target shall M optically deter-
mined and mould bo recorded. If a imoke
imnw plume is selected, it mall mm
the requirements of Section 3 3 of Refer-
ence Method 9. This calibration shall bo
performed in tho field during calm
-------
Ihoptar I—S
Part 60. Aop. A
-« lJ19' Zr

':a :i
- l:aar Recs'. ?¦
» i :no - I a'
7 -e:ec:;r
*ar--,
,:ac •< est
'ieutrji -aensity
oottcal filter
. i .iser zr
; ::e
;nt ::„r:e;
ii^n: ;a*.n
- :ar Peceive>-
"j 3iot:mi,Uisi • ?r
U Oetec.or
',z\ zi :e' "es: ,st.-!u,a:efl oeacity values)
iral' :e Der'crrea witn no aroient ar itray tignt reading :*9
:s*. = : ::r
-jre -Mi-jj. Test Configuration for Tecnmije !
-------
Fart 60. App. A
Till# <0 Protection o# Environment
The tero-tlgnal '.eve( mill be tr.t*sured
and mould oe recorded u indicated 'n
riure AMl-vi(a> This simulated clear air
jr 0°4 opacity -aiue sn»,l se '.tsted in urns
-e selected 'ignt source aspic'.eo in Pgure
AMl-VLb)
Tt~e I'igat source eitrer ir.ail a continu-
ous wave iCW) 'tier ntn the oe&m ue-
cl-snicaily chopped or a i:«nc emitting diode
controlled with a Dulse tererator 'rectangu-
lar pulse' (A I aser kui -my nave 'o oe »t-
'enuated >0 as not to saturate the PMT de-
tector) This signal levei mail be measured
and should ae recorded T~.e ooacity vaiue u
calculated by taking two pica interval* (Sec-
tion 2.S1 about 1 microsecond apart ui tune
and using Equation A.M1-2) >etting the
ratio R,/R,-l Thl* calcinated value mould
be recorded.
The sunulated clear air signal level u also
employed la me optical -.est using tne neu-
trai density filters. Using tne test configura-
tion in Figure AMl-VIfci eacn neutral den-
sity filter ihall be seoarately placed into trie
light path from tne tignt source to tne PMT
detector The signal level snail be measured
and mould B* recorded Tr.e opacity value
for eacn (Liter Is calculated by '.mcing the
signal level for tnat respective later i [,i. di-
viding vt by tne 0"„ opacify signal level t1.)
and performing tne remainder of the calcu-
lation by Equation aim R./R.-1.
The calculated opacity vuue (or eacn (liter
should be recorded.
The neutral density (llten used (or Tech-
nique 1 snail be calibrated for actual ooac-
ity with security of =2% or better This
calibration snail be done montnly while the
(Uteri an in use and tne calibrated value*
should be recorded.
121 Procedure lor Technique 1. An opti-
cal generator (built in calibration mecha-
numi that contain* a itgnc emit tint diode
(red 11 tfit (or a Udar containing a ruby
laser) is used. By injecting an ootlcal signal
into the Udar receiver immediately ahead of
the PMT detector. a backscatter signal is
simulated. With the entire Udar receiver
electronics turned on and adjusted (or
normal opera una perfcrmance. tha optical
generator la tuned on and the simulation
signal (corrected Cor './Rn is aatectaa wta
no plume spue signal tad *un tne opacity
value equal to 0%. This simulated clear-air
imwpftertc rnun signal u displayed on
Um system* video display The tidar opera-
tor Umb make* ur (tne adjustments that
on be nooaaary m tne ayataa t
neemel eeersuns rm«w.
Tfts oo*c«y value* ol 0», and the other
five value* are selected one at a tune in any
order The simulated return signal oau
mould be recorded. The opacity value snail
be calculated. Thii rcea*uriment/cucuja-
cian stiail be performed at [rut three '.use*
(or eacn selected opacity value. While the
order u not ireponani. eacn of the opacity
'•aiuee from tne ootical generator snail ae
¦¦ er-.iied. The calibrated optical generator
opacity value (or eacn selection snouid be
records*.
The opyeal generauir uted (or Technique
1 shall be calibrated for actual opacity «itn
ui accuracy ot =17. or better This calibra-
tion shall be done monthly vtuie the gener-
ator isiauie and calibrated value should be
recorded.
Alternate verification procedure* that do
not meet the above requirement* but pro-
duce equivalent remits may oe used.
3 3 Deviation. The permissible error (or
the annual calibration and routine verifica-
tion are;
3 3 1 Annual Calibration Deviation.
131.1 Smose Oenerator If the lidar-
measured average opacity car eacn dau run
Is not within iJS rfuli wale) ot the reeeec-
tlve smote generator) average opacity over
the range ol 0% through 80%. then the lidar
shall be considered out ot calibration.
3 312 Senna. U the ildar-measured
avarice opacity (or each dau rm is not
within rl% i fun scale) ot tat iaoar*tor?-de-
termined opacity (or each respective simula-
tion screen target over cite range of 0%
through SO*, then th« Lidar shall be consid-
ered out of calibration.
112 Routine VerMtcaUon Error. It the
ildar measured average opacity for each
neutral density (liter (Tectuilaue l) or opti-
cal generator selection (Technique 2] is not
within =3% Uull scale) of tha respective
laboratory calibration value then the Udar
shall be considered non-operattonaL
4. Performance/ Design Specification (or
Basle Udar System.
4.1 Udar Design Specification. The es-
sential components of the basic udar system
an a pulsed laser i transmitter), optical re-
ceiver. detector, signal processor, recorder,
and an device thai la used in aiming
the Udar transmitter and receiver. Figure
AJ*l-'/n thoere a functional block diagram
of a baste Udar system.
-------
Iiuwilli4 I if hi Pull*
IkIuiIIh Bclwa SifMl
HwImn)

i
Adjust to center using range
/

Put this line on zero using
knob on Optical Signal Generator gray vertical position knob
CHANGING THE ATTENTJATQR
1. Pull off the top attenuator and return the Fiber Optic
Cable for first set of calibration measurements. BE
SURE FIBER IS FLUSH WITH JACKET END AND
ALSO GENTLY PUT IN THE CABLE OR
ATTENUATORS.
2. Second set - Return the original attenuator and then put
m the Fiber Optics Cable on top.
3. Third set - Add another attenuator. This attenuator is m
the wooden box. Unscrew at the center of the attenuator
and remove the charcoal-colored filters. Put this
attenuator in on top of the last attenuator and then the
Fiber Optics Cable on top.
4. Fourth set - Remove the last attenuator and put back in
the filters. Put this attenuator with filters back in and
put the Fiber Optics Cable back on.
5. The attenuator needs to be changed when the (right side)
end of the signal on the scope begins to flutter. Also, the
last calibration can be used a3 a guide.
6. Return the first attenuator and Fiber Optics Cable as
before for normal operation.
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II
A. PROGRAM
1. R OSGCAL
Enter PMT voltage in Kilowatts: 1.4 return
Will the Attenuation be changed": N return
Enter scope channel 2 scale (V/DIV): .010 return
Set opacity switch to 0%
Near reading (center on 3rd line to left) return (using
battery box)
Far reading (center on 2nd line) return
Set opacity switch to 10% (repeat)
Set opacity switch to 20%
Set opacity switch to 40%
Set opacity switch to 60%
Set opacity switch to 80%
If any reading that differs by more than ±3% of previous
months calibated opacity, start SRT over (computer
prompts operator)
Change PMT Voltage: 1.5
Same as before
Change PMT Voltage: 1.6
Same as before
2. Turn voltage on battery box all the way down (to the left).
Check and adjust zero.
3. Adjust Battery Box knob to bring bottom line of signal to
center line on the screen. Reason for doing this is to
verify that voltage does not go over 10.24. If over 10.24,
then move Channel 2 Volta/Div to .005 or until voltage is
below 10.24.
4. Channel 2 volt/div should be set to lowest number which
keeps the voltage below 10.24.
5. To a4just the line (bottom), use the Battery Box. To
adjust the zero at left switch from DC to GND, use the
Channel 1 position knob to adjust zero, and switch back
to DC.
Change attenuator - Computer wUl prompt you as to WHEN to change attenuator. Enter
Y for "will attenuation change?" and then follow the computer prompts.
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D-4
, i
i
1
i
1
' 1
i

This is where you line
up the near reading
This is where you line
up the far reading
Go through opacity 0 to 80% on the Optical Signal
Generator and at the end raise PMT voltage by 100 -
Example: 1000 to 1100 or 1100 to 1200 - which is typed at
1.0, 1.1, 1.2, etc., on the computer.
WHEN THE SIGNAL STARTS TO FLAP ON THE FAR END, IT IS TIME
TO CHANGE THE ATTENUATOR.
B.
Volts/Div
2 = .002
m
5 = .005
m
1Q = .01
m
2Q= .02
m
5Q = .05
m
CHANGING THE ATTENUATOR (See Page 2 also)
BEFORE attenuator is changed, do some calculations:
1. Return PMT to last voltage.
Zero the opacity on the Optical Signal Generator.
Line up with center line, using the Battery Box.
Bring line back on scope to center.
2.
3.
4.
5.
Do the last PMT voltage again. If the last one was on
1500, then do 1500 again with the new attenuator.
After this dB number is calculated, you must remember
the last question the computer asked you. Which was:
PMT Voltage. PUT IN THE PMT VOLTAGE.
(EXAMPLE: 1.5 Continue).
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7. Channel 2 Volts/Div should be set for as close to 10.24 on
multimeter as possible without going over 10 24.
8. (Says) Ch2 sensitivity7 (Type) Example: ( 005) Which is
the Channel 2 Volts/Div.
PRINTOUT
1. When all finished and PMT voltage question is on
computer --
(Type) 0 Return
(Says) Are we done? (Type) Y Return
2. Type PR for 004,DAT (latest version) Rename file
(Ex.Cal 490.DAT) where 4 is month and 90 is year.
3. Now put the wires as before the operation.
4. Channel 1 button on scope pushed in.
5. Restore attenuator as it was before the calibration
procedure.
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