Emission Factor Documentation for AP-42
Section 13.2.6
Abrasive Blasting
Final Report
For U. S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Emission Factor and Inventory Group
EPA Contract 68-D2-0159
Work Assignment No. 4-02
MRI Project No. 4604-02
September 1997
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Emission Factor Documentation for AP-42
Section 13.2.6
Abrasive Blasting
Final Report
For U. S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Emission Factor and Inventory Group
Research Triangle Park, NC 27711
Attn: Mr. Ron Myers (MD-14)
EPA Contract 68-D2-0159
Work Assignment No. 4-02
MRI Project No. 4604-02
September 1997
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NOTICE
The information in this document has been funded wholly or in part by the United States
Environmental Protection Agency under Contract No. 68-D2-0159 to Midwest Research Institute. It has
been reviewed by the Office of Air Quality Planning and Standards, U. S. Environmental Protection Agency,
and has been approved for publication. Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.
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PREFACE
This report was prepared by Midwest Research Institute (MRI) for the Office of Air Quality
Planning and Standards (OAQPS), U. S. Environmental Protection Agency (EPA), under Contract
No. 68-D2-0159, Work Assignment Nos. 2-01 and 4-02. Mr. Ron Myers was the requester of the work.
Approved for:
MIDWEST RESEARCH INSTITUTE
Roy Neulicht
Program Manager
Environmental Engineering Department
Jeff Shular
Director, Environmental Engineering
Department
September, 1997
in
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IV
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TABLE OF CONTENTS
Page
1. INTRODUCTION 1-1
2. INDUSTRY AND PROCESS DESCRIPTION 2-1
2.1 INDUSTRY CHARACTERIZATION 2-1
2.2 PROCESS DESCRIPTION 2-1
2.2.1 Types of Abrasives 2-1
2.2.2 Blasting Methods 2-2
2.3 DUST CONTROL TECHNIQUES 2-9
2.3.1 Blast Enclosures 2-9
2.3.2 Vacuum Blasters 2-9
2.3.3 Drapes 2-9
2.3.4 Water Curtains 2-9
2.3.5 Wet Blasting 2-11
2.3.6 Centrifugal Blasters 2-13
2.4 REFERENCES FOR SECTION 2 2-13
3. GENERAL DATA REVIEW AND ANALYSIS 3-1
3.1 LITERATURE SEARCH AND SCREENING 3-1
3.2 DATA QUALITY RATING SYSTEM 3-1
3.3 EMISSION FACTOR QUALITY RATING SYSTEM 3-2
3.4 REFERENCES FOR SECTION 3 3-3
4. EMISSION FACTOR DEVELOPMENT 4-1
4.1 REVIEW OF SPECIFIC DATA SETS 4-1
. 1 Reference 1 4-2
.2 Reference 2 4-2
.3 Reference 3 4-2
.4 Reference 4 4-3
4. .5 Reference 5 4-3
4. .6 Reference 6 4-3
4.2 RESULTS OF DATA ANALYSIS 4-3
4.3 DEVELOPMENT OF CANDIDATE EMISSION FACTORS 4-7
4.4 REFERENCES FOR SECTION 4 4-11
5. PROPOSED AP-42 SECTION 13.2.6 5-1
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LIST OF FIGURES
Figure Page
2-la. Suction blast nozzle assembly 2-4
2-lb. Suction-tape blasting machine 2-4
2-2. Pressure-type blasting machine 2-5
2-3a. Wet blasting machine 2-6
2-3b. Adapter nozzle converting a dry blasting unit to a wet blasting unit 2-6
2-4. Hydraulic blasting nozzle 2-6
2-5. Schematic of vacuum blaster head 2-10
2-6. Nozzle for air abrasive wet blast 2-11
2-7. Water curtain device for abrasive blast nozzle 2-12
LIST OF TABLES
Table Page
2-1. MEDIA COMMONLY USED IN ABRASIVE BLASTING 2-2
2-2. FLOW RATE OF SAND THROUGH A BLASTING NOZZLE AS A
FUNCTION OF NOZZLE PRESSURE AND INTERNAL DIAMETER 2-8
2-3. BULK DENSITY OF COMMON ABRASIVES 2-8
4-1. REFERENCE DOCUMENTS REVIEWED DURING LITERATURE SEARCH 4-1
4-2. SUMMARY OF TEST DATA FOR ABRASIVE BLASTING OPERATIONS 4-4
4-3. SUMMARY OF AVAILABLE CONTROL EFFICIENCY DATA FOR ABRASIVE
BLASTING OPERATIONS 4-6
4-4. SUMMARY OF PM TEST DATA FROM REFERENCE 1 4-8
4-5. SUMMARY OF EMISSION FACTORS FOR PM METALS 4-9
4-6. SUMMARY OF EMISSION FACTORS FOR PM-10 METALS 4-9
4-7. SUMMARY OF EMISSION FACTORS FOR PM-2.5 METALS 4-10
4-7. SUMMARY OF EMISSION FACTORS FOR PM-2.5 METALS 4-10
4-8. CANDIDATE PM-10 AND PM-2.5 EMISSION FACTORS 4-10
4-9. CANDIDATE TOTAL PM EMISSION FACTORS DIFFERENTIATED
BY WIND SPEED 4-10
4-10. CANDIDATE EMISSION FACTOR FOR GARNET BLASTING 4-11
VI
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1. INTRODUCTION
The document Compilation of Air Pollutant Emission Factors (AP-42) has been published by the
U. S. Environmental Protection Agency (EPA) since 1972. Supplements to AP-42 are issued to add new
emission source categories and to update existing emission factors. The EPA also routinely updates AP-42 in
response to the needs of Federal, State, and local air pollution control programs and industry.
An emission factor relates the quantity (weight) of pollutants emitted to a unit of source activity.
Emission factors reported in AP-42 are used to:
1. Estimate areawide emissions.
2. Estimate emissions for a specific facility.
3. Evaluate emissions relative to ambient air quality.
This report provides background information from test reports and other information to support
preparation of a new AP-42 section for abrasive blasting. The information in the proposed AP-42 section is
based on a review of the available literature for particulate phase air pollutants produced by abrasive blasting
operations.
This report contains five sections. Following the introduction, Section 2 describes abrasive blasting
equipment, practices, and allied processes. Section 3 describes data collection and rating procedures, and
Section 4 describes the emission factor development. Section 5 presents the proposed AP-42 section.
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2. INDUSTRY AND PROCESS DESCRIPTION
2.1 INDUSTRY CHARACTERIZATION
Abrasive blasting is used for a variety of surface cleaning and texturing operations, mostly involving
metallic target materials. Sand is the most widely used blasting abrasive. Other abrasive materials include
coal slag, smelter slags, mineral abrasives, metallic abrasives, and synthetic abrasives. Industries that use
abrasive blasting include the shipbuilding industry, automotive industry, and other industries that involve
surface preparation and painting. The majority of shipyards no longer use sand for abrasive blasting because
of concerns about silicosis, a condition caused by respiratory exposure to crystalline silica. In 1991, about
4.5 million tons of abrasives, including 2.5 million tons of sand, 1 million tons of coal slag, 500 thousand
tons of smelter slag, and 500 thousand tons of other abrasives, were used for domestic abrasive blasting
operations.
2.2 PROCESS DESCRIPTION1'8
The following sections briefly describe the types of abrasives, blasting methods, and dust control
techniques commonly used in outdoor abrasive blasting.
2.2.1 Types of Abrasives1'2
Abrasive materials are generally classified as: sand, slag, metallic shot or grit, synthetic, or other.
The cost and properties associated with the abrasive material dictate its application. The following discusses
the general classes of common abrasives.
Silica sand is commonly used for abrasive blasting where reclaiming is not feasible, such as in
unconfmed abrasive blasting operations. Sand has a rather high breakdown rate, which can result in
substantial dust generation. Worker exposure to free crystalline silica is of concern when silica sand is used
for abrasive blasting.
Coal and smelter slags are commonly used for abrasive blasting at shipyards. Black Beauty™,
which consists of crushed slag from coal-fired utility boilers, is a commonly used slag. Slags have the
advantage of low silica content, but have been documented to release other contaminants, including
hazardous air pollutants (HAP), into the air.
Metallic abrasives include cast iron shot, cast iron grit, and steel shot. Cast iron shot is hard and
brittle and is produced by spraying molten cast iron into a water bath. Cast iron grit is produced by crushing
oversized and irregular particles formed during the manufacture of cast iron shot. Steel shot is produced by
blowing molten steel. Steel shot is not as hard as cast iron shot, but is much more durable. These materials
typically are reclaimed and reused.
Synthetic abrasives, such as silicon carbide and aluminum oxide, are becoming popular substitutes
for sand. These abrasives are more durable and create less dust than sand. These materials typically are
reclaimed and reused.
Other abrasives include mineral abrasives (such as garnet, olivine, and staurolite), cut plastic, glass
beads, crushed glass, and nutshells. As with metallic and synthetic abrasives, these other abrasives are
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generally used in operations where the material is reclaimed. Mineral abrasives are reported to create
significantly less dust than sand and slag abrasives.
The type of abrasive used in a particular application is usually specific to the blasting method. Dry
abrasive blasting is usually done with sand, aluminum oxide, silica carbide, metallic grit, or shot. Wet
blasting is usually done with sand, glass beads, or any materials that will remain suspended in water.
Table 2-1 lists common abrasive materials and their applications.
TABLE 2-1. MEDIA COMMONLY USED IN ABRASIVE BLASTING2
Type of medium
Sizes normally available
Applications
Glass beads
Aluminum oxide
Garnet
Crushed glass
Steel shot
Steel grit
Cut plastic
Crushed nutshells
8 to 10 sizes from 30- to 440-mesh;
also many special gradations
10 to 12 sizes from 24- to 325-mesh
6 to 8 sizes (wide-band screening) from
16- to 325-mesh
5 sizes (wide-band screening) from 30-
to 400-mesh
12 or more sizes (close gradation) from
8- to 200-mesh
12 or more sizes (close gradation) from
10-to 325-mesh
3 sizes (fine, medium, coarse); definite-
size particles
6 sizes (wide-band screening)
Decorative blending; light deburring;
peening; general cleaning; texturing;
noncontaminating
Fast cutting; matte finishes; descaling
and cleaning of coarse and sharp
textures
Noncritical cleaning and cutting;
texturing; noncontaminating for
brazing steel and stainless steel
Fast cutting; low cost; short life;
abrasive; noncontaminating
General-purpose rough cleaning
(foundry operation, etc.); peening
Rough cleaning; coarse textures;
foundry welding applications; some
texturing
Deflashing of thermoset plastics;
cleaning; light deburring
Deflashing of plastics; cleaning; very
light deburring; fragile parts
2.2.2 Blasting Methods2'8
Abrasive blasting systems typically include three basic components: an abrasive container (i.e.,
blasting pot), a propelling device, and an abrasive blasting nozzle(s). The exact equipment used depends on
the application.
The three propelling methods used in abrasive blasting systems are: centrifugal wheels, air pressure,
or water pressure. Centrifugal wheel systems use centrifugal and inertial forces to mechanically propel the
abrasive media.3 Air blast systems use compressed air to propel the abrasive to the surface being cleaned.4
Finally, the water blast method uses either compressed air or high pressure water.
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The compressed air suction, the compressed air pressure, and the wet abrasive blasting systems utilize the air
blast method. Hydraulic blasting systems utilize the water blast method.
In compressed air suction systems, two rubber hoses are connected to a blasting gun. One hose is
connected to the compressed-air supply and the other is connected to the bottom of the abrasive supply tank
or "pot." The gun (Figure 2-la) consists of an air nozzle that discharges into a larger nozzle. The high
velocity air jet (expanding into the larger nozzle) creates a partial vacuum in the chamber. This vacuum
draws the abrasive into the outer nozzle and expels it through the discharge opening. Figure 2- Ib shows a
typical suction type blasting machine.
The compressed air pressure system consists of a pressure tank (pot) in which the abrasive is
contained. The use of a pressure tank forces abrasive through the blast hose rather than siphoning it as
described above. The compressed air line is connected to both the top and bottom of the pressure tank. This
allows the abrasive to flow by gravity into the discharge hose without loss of pressure (see Figure 2-2).
Finally, wet abrasive blasting systems (Figure 2-3 a) use a specially designed pressure tank. The
mixture of abrasive and water is propelled by compressed air. An alternate method uses a pressure tank and
a modified abrasive blasting nozzle. This modified abrasive blasting nozzle is shown in Figure 2-3b.
Hydraulic blasting incorporates a nozzle similar to that described above for air suction systems,
except that high pressure water is used as the propelling media instead of compressed air. A diagram of this
type of nozzle is shown in Figure 2-4.
Pressure blast systems generally give a faster, more uniform finish than suction blast systems. They
also produce high abrasive velocities with less air consumption than suction systems. Pressure blast systems
can operate at pressures as low as 1 psig to blast delicate parts and up to 125 psig to handle the most
demanding cleaning and finishing operations.2
Suction blast systems are generally selected for light-to-medium production requirements, limited
space, and moderate budgets. These systems can blast continuously without stopping for abrasive changes
and refills.2
The amount of sand used during blasting operations can be estimated using Table 2-2. By knowing
the inside diameter of the nozzle (inches) and the air pressure supplied (psig), the sand flow rate is provided.
For different abrasives and nozzle diameters, Equation 2-1 can be used.2
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Gasket
Air nozzle
Nozzle
Suction nozzle
body
Figure 2- la. Suction blast nozzle assembly.
'•:•:•:!:; Abrasive
Abrasive drawn into
gun by suction
Air —
Figure 2- Ib. Suction-tape blasting machine.
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Abrasive control t
Air supply valve
Air
Choke relief valve
Equal air pressure
above and below
abrasive
Figure 2-2. Pressure-type blasting machine.
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Water
'••••^•— Air
Air supply valve
Choke relief valve
Equal air pressure
above and below
abrasive
Figure 2-3a. Wet blasting machine.
Water
Figure 2-3b. Adapter nozzle converting a dry blasting unit to a wet blasting unit.
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Water
Abrasives
/
Figure 2-4. Hydraulic blasting nozzle.
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where:
m = m
(D)2
Pa
Ps
ma = mass flow rate (Ib/hr) of abrasive with nozzle internal diameter Da
ms = mass flow rate (Ib/hr) of sand with nozzle internal diameter Ds from Table 2-2
actual nozzle internal diameter (in.)
nozzle internal diameter (in.) from Table 2-2
ps = bulk density of sand (lb/ft3)
pa = bulk density of abrasive (lb/ft3)
Da =
Ds =
(2-1)
TABLE 2-2. FLOW RATE OF SAND THROUGH A BLASTING NOZZLE AS A
FUNCTION OF NOZZLE PRESSURE AND INTERNAL DIAMETER2
Nozzle
internal
diameter, in.
1/8
3/16
1/4
5/16
3/8
7/16
1/2
5/8
3/4
1
Sand flow rate through nozzle, Ib/hr
Nozzle pressure, psig
30
28
65
109
205
285
385
503
820
1,140
2,030
40
35
80
138
247
355
472
615
990
1,420
2,460
50
42
94
168
292
417
560
725
1,170
1,670
2,900
60
49
107
195
354
477
645
835
1,336
1,915
3,340
70
55
122
221
377
540
755
945
1,510
2,160
3,780
80
63
135
255
420
600
820
1,050
1,680
2,400
4,200
90
70
149
280
462
657
905
1,160
1,850
2,630
4,640
100
77
165
309
507
720
940
1,265
2,030
2,880
5,060
The densities of several different abrasives are shown in Table 2-3.
TABLE 2-3. BULK DENSITY OF COMMON ABRASIVES2
Type of abrasive
Aluminum oxides
Sand
Steel
Density, lb/ft3
160
99
487
2-S
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2.3 DUST CONTROL TECHNIQUES2'4'6'7
A variety of techniques have been used to contain and recover the debris generated during abrasive
cleaning operations. These techniques may be categorized into the following: blast enclosures, vacuum
blasters, drapes, water curtains, wet blasters, and centrifugal blasters. Brief descriptions of each are provided
below. A more detailed discussion of each method can be found in Reference 6.
2.3.1 Blast Enclosures
Blast enclosures are designed to completely enclose one or more abrasive blast operations, thereby
confining the blast debris. The enclosure floor is usually equipped with funnels to divert the captured debris
into adjacent trucks. In one design, a ventilation system is used to remove the airborne dust from the
enclosure with the particles removed from the effluent airstream by a wet scrubber. The enclosures are
moved as the work progresses.
Blast enclosures can be very effective in containing and recovering abrasive blast debris. However,
they are specifically designed for a particular application, relatively expensive, and tend to slow down the
overall cleaning rate due to the time required to move the enclosure as the work progresses.
Some leakage of abrasive and paint debris can occur at the joints between the blast enclosure and the
structure being cleaned. Although attempts have been made to seal the joints with canvas, this is usually not
very effective, particularly when the blast is directed into these areas. A better method to minimize leakage
from enclosure joints is to fasten a flexible seal made of rubber, plastic, or thin metal to the inside edges of
the enclosure walls. The end of the flexible seal rests on the structure being cleaned, thus reducing the escape
of airborne dust.
2.3.2 Vacuum Blasters
Vacuum blasters are designed to remove paint and other surface coatings by abrasive blasting and
simultaneously collect and recover the spent abrasive and paint debris with a capture and collection system
surrounding the blast nozzle (Figure 2-5). In this type of system, the abrasive is automatically reclaimed and
reused as work progresses. Vacuum blasters are made in a variety of sizes but even the smaller units are
comparatively heavy and awkward to use. Furthermore, the production rates of the small units are low, and
costs are relatively high.
2.3.3 Drapes
Porous drapes (or curtains) on both sides of a truss-type structure (e.g., bridge) have been used to
divert debris downward into a barge or lined net under the blasting operation. The top of the drapes are tied
to the top of the structure. This technique is relatively inexpensive but also not very effective because dust
penetrates the porous drape and spillage occurs due to wind effects.
2.3.4 Water Curtains
In this technique, a water header with a series of nozzles is installed along the edges of the structure
being blasted. The water spray from the nozzles is directed downward creating a water curtain to collect
debris from abrasive blasting performed below the header. The debris is subsequently washed down to the
ground. This technique is relatively inexpensive and does reduce the amount of airborne dust.
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Control Valve
To
Separator
Vacuum
Hose
Ejector
Nozzle
Blast
Nozzle
Vacuum
Recovery
Head
Inner
Cone
Figure 2-5. Schematic of vacuum blaster head.
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However, one disadvantage is that the debris-laden water spills onto the ground (or into the water under a
bridge) creating additional contamination and clean-up problems.
One method used to solve the spillage problem associated with water curtains involves the placement
of troughs under the spray pattern to catch the water/abrasive mixture and divert it to an appropriate
container (e.g., tank truck) for disposal. For low structures, the troughs can be placed on the ground. For
high structures, the troughs can be supported from the structure itself. To minimize wind effects, porous
drapes can be added, extending from the blast area down to the troughs.
2.3.5 Wet Blasting
Wet blasting techniques include: wet abrasive blasting; high-pressure water blasting; high-pressure
water and abrasive blasting; and air and water abrasive blasting. The type of wet blasting method used
depends on the application.
Wet abrasive blasting is accomplished by adding water to conventional abrasive blasting nozzles as
shown in Figure 2-6. High-pressure water blast systems include an engine-driven, high-pressure pump, high-
pressure hose, and a gun equipped with a spray nozzle. If abrasives are introduced to this type of system,
high-pressure water and abrasive blasting is provided. Finally, in air and water abrasive blasting systems,
each of the three materials can be varied over a wide range, making them very versatile. Compared to dry
blasting, all wet blasting techniques produce substantially lower dust emissions.
Pressurized
Water
Needle Valve
Nozzle Adapter
Nozzle
Nozzle
Holder
Abrasive
and Air
Water
Jets
\
Atomized
Water
Injector
Figure 2-6. Nozzle for air abrasive wet blast.
Air
Abrasive
Water
Most wet abrasive blasters mix the water with the abrasive prior to impact on the surface. This
interaction can cause the rate of surface cleaning to be lower than with dry abrasive blasting. To solve this
problem, a retrofit device (design to minimize premixing of the water with the abrasive blast) has been
developed to fit over the end of conventional abrasive blast nozzles. This device is shown in Figure 2-7.
The two principal parts of the device (Figure 2-7) are a swirl chamber and an exit nozzle. The swirl
chamber is equipped with a tangential water inlet. The incoming water swirls around the inside of the
chamber and then out the exit nozzle. Centrifugal force causes the water to form a hollow cone pattern
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Set Screws (E)
Abrasive
V" Blast
\ Nozzle
\
L
Water Line
(D)
Water Curtain Device
Water Curtain
(a) Overall View of Concept
L
Swirl Chamber (A)
%/A
\
Exit Nozzle (B)
Water Inlet (C)
(lor 2)
n Alternate
11 Second
Inlet
(b) Cross Section
(c ) Front View
Figure 2-7. Water curtain device for abrasive blast nozzle.
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around the abrasive blast stream. The angle of the water cone is controlled principally by the shape of the
exit nozzle and centrifugal forces.
The above device is expected to be an improvement over traditional wet abrasive blasting. The
modified water nozzle design provides a water curtail around the abrasive/airstream. Thus, the cleaning
effectiveness of the abrasive/airstream should not be substantially affected. The device is simple to install
and operate with conventional abrasive blasting equipment.
2.3.6 Centrifugal Blasters
Finally, centrifugal blasters use high-speed rotating blades to propel the abrasive against the surface
to be cleaned. These blasters also retrieve and recycle the abrasive by the use of a capture and collection
system which allows little abrasive or paint debris to escape. Present centrifugal blasters are designed
primarily for large, flat, horizontal surfaces such as ship decks. Some have been designed for use on large
vertical surfaces such as ship hulls and storage tanks. Some effort has been made to develop small hand-held
units for use on bridges and similar structures.
2.4 REFERENCES FOR SECTION 2
1. Written communication from J. D. Hansink, Barton Mines Corporation, Golden, CO, to Attendees of
the American Waterways Shipyard Conference, Pedido Beach, AL, October 28, 1991.
2. South Coast Air Quality Management District, Section 2: Unconfmed Abrasive Blasting, Draft
Document, El Monte, CA, September 8, 1988.
3. A. W. Mallory, "Guidelines for Centrifugal Blast Cleaning," J. Protective Coatings and Linings,
1(1), June 1984.
4. B. Baldwin, "Methods of Dust-free Abrasive Blast Clearing" Plant Engineering, 32(4),
February 16, 1978.
5. B. R Appleman and J. A. Bruno, Jr., "Evaluation of Wet Blast Cleaning Units," J. Protective
Coatings and Linings, 2(8), August 1985.
6. M. K. Snyder and D. Bendersky, Removal of Lead-based Bridge Paints, NCHRP Report 265,
Transportation Research Board, Washington, DC, December 1983.
7. J. A. Bruno, "Evaluation of Wet Abrasive Blasting Equipment," Proceedings of the 2nd Annual
International Bridge Conference, Pittsburgh, PA, June 17-19, 1985.
8. J. S. Kinsey, Assessment of Outdoor Abrasive Blasting, Interim Report, EPA Contract No. 68-02-
4395, Work Assignment No. 29, U. S, Environmental Protection Agency, Research Triangle Park,
NC, September 11, 1989.
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3. GENERAL DATA REVIEW AND ANALYSIS
3.1 LITERATURE SEARCH AND SCREENING
The first step of this investigation was a search of the available literature relating to the particulate
emissions associated with open abrasive blasting. This search included data contained in the open literature
(e.g., National Technical Information Service); source test reports and background documents located in the
files of the EPA's Office of Air Quality Planning and Standards (OAQPS); data base searches (e.g.,
SPECIATE); and MRI's own files (Kansas City and North Carolina). The search was an update of the
extensive information collection effort performed in 1989 as reported in Reference 1.
To evaluate candidate documents for acceptability as sources of emission data, the following general
criteria were used:
1. Emissions data must be taken only from a primary reference:
a. Source testing data must be obtained directly from a referenced study that does not reiterate
information from previous studies.
b. The document must constitute the original source (or publication) of the test data.
2. The report must contain sufficient data to evaluate the testing procedures and source operating
conditions.
A final set of reference materials was compiled after a thorough review of the pertinent reports,
documents, and information according to the above criteria. This set of documents was further analyzed to
derive candidate emission factors for abrasive blasting operations.
3.2 DATA QUALITY RATING SYSTEM
As part of MRI's analysis, the final set of reference documents was evaluated as to the quantity and
quality of data. The following data were always excluded from consideration:
1. Test series averages reported in units that cannot be converted to the selected reporting units.
2. Test series representing incompatible test methods.
3. Test series in which the control device (or equipment) is not specified.
4. Test series in which the abrasive blasting process is not clearly identified and described.
5. Test series in which it is not clear whether the emissions were measured before or after the control
device.
If there was no reason to exclude a particular data set, each was assigned a rating as to its quality.
The rating system used was that specified by the EPA's Office of Air Quality Planning and Standards
(OAQPS) for the preparation of AP-42 Sections.2 The data were rated as follows:
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A—Multiple tests performed on the same source using sound methodology and reported in enough
detail for adequate validation. These tests do not necessarily have to conform to the methodology specified
by EPA reference test methods, although such were certainly used as a guide.
B—Tests that are performed by a generally sound methodology, but they lack enough detail for
adequate validation.
C—Tests that are based on an untested or new methodology or that lack a significant amount of
background data.
D—Tests that are based on a generally unacceptable method, but the method may provide an order-
of-magnitude value for the source.
The following criteria were used to evaluate source test reports for sound methodology and adequate
detail:
1. Source operation. The manner in which the source was operated is well documented in the report.
The source was operating within typical parameters during the test.
2. Sampling procedures. The sampling procedures conformed to a generally accepted methodology.
If actual procedures deviated from accepted methods, the deviations were well documented.
3. Sampling and process data. Adequate sampling and process data were documented in the report.
Many variations may be unnoticed and occur without warning during testing. Such variations can induce
wide deviations in sampling results. If a large spread between test results cannot be explained by information
contained in the test report, the data are suspect and were given a lower rating.
4. Analysis and calculations. The test reports contain original raw data sheets. The nomenclature
and equations used were compared to those specified by EPA (if any) to establish equivalency. The depth of
review of the calculations was dictated by the reviewer's confidence in the ability and conscientiousness of the
tester, which in turn was based on factors such as consistency of results and completeness of other areas of
the test report.
3.3 EMISSION FACTOR QUALITY RATING SYSTEM
The quality of the emission factors developed from analysis of the test data was rated utilizing the
following general criteria:
A—Excellent: Developed from A- and B-rated source test data taken from many randomly chosen
facilities in the industry population. The source category is specific enough so that variability within the
source category population may be minimized.
B—Above average: Developed only from A- or B-rated test data from a reasonable number of
facilities. Although no specific bias is evident, it is not clear if the facilities tested represent a random sample
of the industries. The source category is specific enough so that variability within the source category
population may be minimized.
C—Average: Developed only from A-, B- and/or C-rated test data from a reasonable number of
facilities. Although no specific bias is evident, it is not clear if the facilities tested represent a random sample
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of the industry. In addition, the source category is specific enough so that variability within the source
category population may be minimized.
D—Below average: The emission factor was developed only from A-, B-, and/or C-rated test data
from a small number of facilities, and there is reason to suspect that these facilities do not represent a random
sample of the industry. There also may be evidence of variability within the source category population.
Limitations on the use of the emission factor are noted in the emission factor table.
E—Poor: The emission factor was developed from C- and D-rated test data, and there is reason to
suspect that the facilities tested do not represent a random sample of the industry. There also may be
evidence of variability within the source category population. Limitations on the use of these factors are
footnoted.
The use of these criteria is somewhat subjective and depends to an extent upon the individual
reviewer. Details of the rating of each candidate emission factor are provided in Section 4.
3.4 REFERENCES FOR SECTION 3
1. J. S. Kinsey, Assessment of Outdoor Abrasive Blasting, Interim Report, EPA Contract No. 68-02 4395,
Work Assignment No. 29, U. S. Environmental Protection Agency, Research Triangle Park, NC,
September 11, 1989.
2. Procedures for Preparing Emission Factor Documents, EPA-454/R-95-015, Office of Air Quality
Planning and Standards, U. S. Environmental Protection Agency, Research Triangle Park, NC,
May 1997.
3-3
-------
4. EMISSION FACTOR DEVELOPMENT
4.1 REVIEW OF SPECIFIC DATA SETS
In the prior information search of the literature for documents on the subject of abrasive blasting,
37 individual documents were identified for further evaluation.1 Upon subsequent review of these
documents, 15 were determined to contain some type of applicable air monitoring data. Of these 15 docu-
ments, only 9 contained data which were found to be potentially useful in the development of candidate
emission factors. Those documents are listed in Table 4-1.
TABLE 4-1. REFERENCE DOCUMENTS REVIEWED DURING LITERATURE SEARCH
Samimi, B., "Silica Dust in Sandblasting Operations," Ph.D. Thesis, Tulane University, 1973.
Samimi, B., et al., "Dust Sampling Results at a Sandblasting Yard Using Stan-Blast in the New
Orleans Region: A Preliminary Report," NIOSH-00036278, New Orleans, LA, 1974.
Samimi, B., et al., "The Efficiency of Protective Hoods Used by Sandblasters to Reduce Silica Dust
Exposure," Am. Indus. Hyg. Assn. J., 36(2), February 1975.
Landrigan, P. J., et al., "Health Hazard Evaluation Report on the Tobin-Mystic River Bridge,"
TA80-099-859, NIOSH Report to City Boston Department of Health and Hospitals, Boston, MA,
July 25, 1980.
Bareford, P. E., and F. A. Record, "Air Monitoring at the Bourne Bridge Cape Cod Canal,
Massachusetts," Final Report, Contract No. DACW 33-79-C-0126, U.S. Army Corps of Engineers,
New England Division, Waltham, MA, January 1982.
Beddows, N. A., "Lead Hazards and How to Control Them," Natl. Safety News, 128(6), December
1983.
Lehner, E., et al., Memo to D. M. Moline, Department of Public Utilities, Division of Environmental
Services, City of Toledo, OH, January 31, 1985.
WhiteMetal, Inc., "Protecting Our Environment with the Jet Stripper," Houston, TX, June 1987.
South Coast Air Quality Management District, "Section 2: Unconfmed Abrasive Blasting," Draft
Document, El Monte, CA, September 8, 1988.
Besides the documents listed in Table 4-1, the ongoing literature search yielded seven additional test
reports, as listed below.
1. Kinsey, J. S., et al., "Development of Particulate Emission Factors for Uncontrolled Abrasive
Blasting Operations," U. S. Environmental Protection Agency, Research Triangle Park, NC, February 1995.
2. NEESA 2-161. Particulate and Chromium Emission Testing at Plastic Media Blasting Facility,
BLDG 25, Naval Aviation Depot, Naval Air Station, Alameda, CA, Naval Energy and Environmental
Support Activity, PortHueneme, CA, May 1990.
3. Determination of Particulate Emission Rates & Baghouse Removal Efficiency, Hamilton
Foundry, Harrison, Ohio, K&B Design, Inc., Cincinnati, OH, September 3, 1991.
4. Written Communication from D. Borda, The Hamilton Foundry & Machine Co., Harrison, OH, to
L. Gruber, Southwestern Ohio Air Pollution Control Agency, Cincinnati, OH, November 27, 1990.
4-1
-------
5. Summary of Source Test Results, Hunter Schlesser Sandblasting, San Leonardo, CA, Bay Area
Air Quality Management District, San Francisco, CA, March 3, 1993.
6. Summary of Source Test Results, Poly Engineering, Richmond, CA, Bay Area Air Quality
Management District, San Francisco, CA, November 19, 1990.
One additional report (Peart, J., et al. [title unknown] Federal Highway Administration, Washington, DC,
1995.) was requested from the Federal Highway Administration in March 1995 but never received.
References 2 through 6 (listed above) document emission tests on enclosed abrasive blasting operations.
Brief reviews of References 1 through 6 are provided in the following paragraphs.
4.1.1 Reference 1
The most definitive study in terms of data quality and documentation was reported by Kinsey et al.,
as cited above. The reported (uncontrolled) emission factors were based on actual air emissions data from a
pilot-scale test facility within which full-scale abrasive blasting (surface cleaning) was performed. This
entailed the construction and use of a low speed wind tunnel that was large enough to house commercially
available abrasive (sand) blasting equipment. Conventional EPA stack sampling and analysis procedures
were used in each test to determine emissions of particulate matter (PM) and HAP metals generated by
abrasive blasting of mild steel panels (automobile hoods and tank sides) with silica sand. The ten HAP
metals are arsenic (As), beryllium (Be), cadmium (Cd), cobalt (Co), chromium (Cr), manganese (Mn), nickel
(Ni), lead (Pb), antimony (Sb), and selenium (Se). Iron (Fe) emissions also were measured. Duplicate test
runs were conducted at each of nine test conditions covering the nominal range of wind speeds (5, 10, and
15 mph) and types of cleaned surfaces (precleaned, painted, and rusted). Emissions and facility operating
data were collected for each test condition. Finally, uncontrolled PM emission factors were developed for
each test condition. The data from this document are assigned an A rating. The EPA reference test methods
were used, adequate detail was provided, and no problems were reported.
4.1.2 Reference 2
This reference documents an emission test conducted on an enclosed abrasive blasting operation at a
California Naval Aviation Depot. Particulate matter, chromium, and hexavalent chromium emissions were
measured at the outlets of two fabric filters that control emissions from the blasting operations. A modified
EPA Method 5 sampling train was used to measure PM emissions, and CARB Method 425 was used to
measure chromium and hexavalent chromium. The blasting operations use plastic media as the blasting
abrasive. The test report does not include process rates, and emission factors could not be developed from
the data. The PM concentrations measured during the test averaged 3.61 mg/dscm (0.00158 gr/dscf). The
chromium concentrations averaged 0.00187 mg/dscm (8.17xlO"7 gr/dscf) and the hexavalent chromium
concentrations averaged 0.000950 mg/dscm (4.12xlO"7 gr/dscf). These data are not rated for use in
developing emission factors.
4.1.3 Reference 3
This reference documents an emission test conducted on an enclosed abrasive blasting operation at
Hamilton Foundry in Harrison, Ohio, on August 20 and 21, 1991. Particulate matter emissions were
measured at the inlet and outlet of a fabric filter that controls emissions from the blasting operations and
several other plant processes. The fabric filter collection efficiency was 99.9 percent during testing. The
results from this test are not useful because several processes are ducted to the fabric filter that was tested.
4-2
-------
4.1.4 Reference 4
This reference documents an emission test conducted on an enclosed abrasive blasting operation at
Hamilton Foundry in Harrison, Ohio, on October 30, 1990. Particulate matter emissions were measured at
the inlet and outlet of a fabric filter that controls emissions from the blasting operations and several other
plant processes. The fabric filter collection efficiency was 99.9 percent during testing. The results from this
test are not useful because several processes are ducted to the fabric filter that was tested.
4.1.5 Reference 5
This reference documents an emission test conducted on an enclosed abrasive blasting operation at
Hunter Schlesser Sandblasting in San Leanardo, CA, on February 10, 1993. Particulate matter emissions
were measured at the outlet of a fabric filter that controls emissions from blasting operations. Three CARB
Method 5 test runs were completed, and the average PM concentration was 2.3 mg/dscm (0.001 gr/dscf).
Glass beads were used as the blast media, and the targeted surfaces included two large motor shields and
several handrails. Process rates are not provided in the report.
4.1.6 Reference 6
This reference documents an emission test conducted on an enclosed abrasive blasting operation at
Poly Engineering in Richmond, CA, on February 10, 1993. Filterable PM emissions were measured at the
outlet of a fabric filter that controls emissions from blasting operations. Three CARB Method 5 test runs
were completed, and the average PM concentration was 0.055 gr/dscf. A CARB certified 30/40 mesh garnet
was used as the blast media, and the targeted surface was unspecified parts. Process rates are provided (Ib/hr
of abrasive) in the report, and emission factors were developed in units of lb/1,000 Ib of abrasive used. The
test report contains incomplete documentation of the stack test data.
The data from this report are assigned a C rating because of the level of detail provided in the report.
The test methodology appeared to be sound and no problems were reported. However, sufficient data are not
included in the report to allow for a complete review of the test.
4.2 RESULTS OF DATA ANALYSIS
The individual data sets were evaluated using the criteria and rating system developed by the EPA's
Office of Air Quality Planning and Standards for the development of AP-42 emission factors. This scheme
entails the rating of test data quality followed by the rating of the adequacy of the data base relative to the
characterization of uncontrolled emissions from the source.
A summary of the available test data for uncontrolled and controlled abrasive blasting operations are
provided in Tables 4-2 and 4-3.
A number of comments should be made with regard to the data contained in Tables 4-2 and 4-3. In
the case of Table 4-2, only four of the twelve data sets contained enough information to develop PM and/or
lead emission factors for abrasive blasting operations. Six of the other studies involved some type of
industrial hygiene or ambient air monitoring in the vicinity of the blasting operation. None of the industrial
hygiene/ambient air studies characterized the blasting operation in sufficient detail for further analysis and
emission factor development. Finally, two of the tests did not include process rates. Two
4-3
-------
TABLE 4-2. SUMMARY OF TEST DATA FOR ABRASIVE BLASTING OPERATIONSa
Reference
document
Samini, 1973;
Samini et al.,
1975
Samini et al.,
1974
Landrigan et
al., 1980
Bareford and
Record, 1982
Beddows,
1983
Lehner et al.,
1985
Type of operation
tested
Outdoor sandblasting
at two steel
fabrication yards
Abrasive cleaning of
ship hull
Abrasive bridge
cleaning of lead-based
paint
Abrasive bridge
cleaning of lead-based
paint
General abrasive
blasting of lead-based
paint
Abrasive bridge
cleaning of lead-based
paint
Type of
abrasive
Silica sand
Stan-Blast
Grit (Black
Beauty)
Sand
Grit
Sand
Sampler location
Within 5 yd (4.6 m) of
sandblaster
< 5 yd (4.6 m) from
source
Sandblaster's chest
< 10 yd (9.1 m)from
source
27 m downwind of
bridge
Center of plume exiting
sandblasting bay
Breathing zone
samples
300-400 ft (91-122 m)
downwind of bridge
Particle size
fraction,
umAb
TP
<11
RP
TP
RP
RP
RP
<11
TSP (Pb)
TP
TP (Pb)
<10
< 10 (Pb)
TP
TSP
TSP (Pb)
lime weighted
average
concentration,
mg/m3
1.46-76.8
11.8
0.109-8.93
10.2
4.58
88.8
2.26-9.88
6.98
0.0129
"
—
—
3-30+
0.339-0.482
0.00122-
0.00215
Data
quality
rating
NR
NR
NR
NR
NR
NR
NR
NR
NR
D
D
D
D
NR
NR
NR
Emission
factor,
mass/source
extent
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
57-455 lb/h/
sandblaster
1.5-4.8 lb/h/
sandblaster
24 lb/h/
sandblaster
0.46 lb/h/
sandblaster
N/A
N/A
N/A
Comments
31 samples; no process data
16 sample average; no process data
29 samples; no process data
Sampling time = 1 85 min
Blasting time = 1 80 min; no process data
Sampling time = 181 min; blasting time =
150 min; no process data
No process data available
Data for a 6.1-h sampling period during
which canvas shroud was not in place for a
2-h period; Pb contributions from paint
chips, vehicle exhaust, and grit; no process
data available
2.5% Pb for particles < 2.4 urn; sand
usage — 700 lb/h per blaster (no exact
throughput available)
< 1% Pb for particles > 75 urn; sand
usage — 700 lb/h per blaster (no exact
throughput available)
Sand usage — 700 lb/h per blaster (no exact
throughput available)
Sand usage — 700 lb/h per blaster (no exact
throughput available)
8-h time- weighted averages; grit from coal
slag typically contains from 20-40 ug of Pb/g
of material; grit from copper smelting can
contain up to 6,000 ug Pb/g of material; no
process data reported
24-h time- weighted averages; no process
data or controls specified; assumed to be
essentially uncontrolled
-------
TABLE 4-2. (continued)
Reference
document
WhiteMetal
Inc., 1987
South Coast
Air Quality
Management
District, 1988
Kinsey et al.,
1995
NEESA
2-161,1990
Hunter
Schlesser
Sandblasting,
1993
Poly
Engineering,
1990
Type of operation
tested
Outdoor blasting of
steel panels coated
with lead-based paint
Outdoor abrasive
blasting
Blasting of molded
steel panels,
painted, cleaned, or
rusted
Enclosed blasting of
aircraft parts
Enclosed blasting of
motor shields and
handrails
Enclosed blasting of
unspecified parts
Type of
abrasive
30-60 mesh
(0.59-0.25
mm) silica
sand
Sand
Grit
Shot
Other
30-50 mesh
silica sand
Plastic
Glass beads
Garnet
Sampler location
5 ft (1 .5 m) downwind
50 ft (15 m) downwind
100 ft (30m)
downwind
200 ft (61 m)
downwind
500 ft (152m)
downwind
In ventilation system
duct
40 ft (12 m) downwind
Fabric filter stack
Fabric filter stack
Fabric filter stack
Particle size
fraction,
umAb
TSP
TSP
TSP
TSP
TSP
TP
TP
TP
TP
TP,<10,
<2.5
TP
TP
TP
lime weighted
average
concentration,
mg/m
257.61
45.99
6.18
2.71
0.90
N/A
N/A
N/A
N/A
See Reference 1
3.61
2.3
126
Data
quality
rating
NR
NR
NR
NR
NR
D
D
D
D
A
NR
NR
C
Emission
factor,
mass/source
extent
N/A
N/A
N/A
N/A
N/A
0.041 Ib/lb
sand
0.010 Ib/lb
grit
0.004 Ib/lb
shot
0.010 Ib/lb
abrasive
See Table 4-4
N/A
N/A
0.00069 Ib/lb
garnet
Comments
Hi-vols installed downwind of dry blasting
operation to demonstrate control
effectiveness of "Jet Stripper"; no sampling
time or process data reported
Emission factors determined by source test
of an uncontrolled indoor blasting operation
using a quasi-slack technique; original test
report not available
Emission factors determined by source tests
in low speed wind tunnel using standard test
methods for total participate, particle size
distribution, and iron and 10 HAP metals
Fabric filter-controlled plastic media blast
room. No process data. Chromium cone, of
0.00187 mg/m3 and Cr+6 cone, of 0.00095
mg/m3
Fabric filter-controlled glass bead blast room.
No process data.
1,740 Ib/hr of abrasive used to blast
700 Ib/hr of parts
aFrom references listed in Table 4-1. N/A = not available or not applicable. NR = not rated.
TP = total participate matter. RP = respirable participate matter (< 3.5 umA) as determined using a 10-mm nylon cyclone followed by a 37-mm filter cassette. TSP = total
suspended participate matter (< 30-50 umA) as determined by a high volume air sampler.
-------
TABLE 4-3. SUMMARY OF AVAILABLE CONTROL EFFICIENCY DATA FOR ABRASIVE BLASTING OPERATIONS51
Reference
document
WhiteMetal Inc.,
1987
So. Coast Air
Quality
Management
District, 1988
Type of operation
tested
Outdoor blasting of
steel panels coated
with lead-base paint
Outdoor abrasive
blasting
Type of
abrasive
30-60 mesh
(250-590 urn)
silica sand
All
Control
technology
employed
Water jet blasting
nozzle (i.e., "Jet
Stripper")
Wet blasting (as
compared to dry
blasting)
Sampler location
5 ft (1.5m)
downwind
50 ft (15m)
downwind
100 ft (30m)
downwind
200 ft (61 m)
downwind
500 ft (152m)
downwind
Particle
size
fraction,
umAb
TSP
TSP
TSP
TSP
TSP
TP
Average dust concentration,
mg/m
Uncontrolled
257.6
46.0
6.2
2.7
0.90
NA
Controlled
42.3
3.3
0.55
0.32
0.19
NA
Measured
control
efficiency
84
93
91
88
79
50%
Comments
Comparison of
uncontrolled and
controlled dust
concentrations
assumes identical
test conditions;
original test data not
available; no process
data or sampling
time reported.
No basis of control
estimate provided
aFrom references listed in Table 4-1. NA = not available.
TSP = total suspended participate matter (~ <30-50 umA) as determined by a high volume air sampler. TP = total participate matter.
-------
additional studies (not shown in Table 4-2) had sufficient information to develop emission factors, but the
stacks that were tested ducted emissions from abrasive blasting and other sources.
Several problems were also noted with the Bareford and Record and South Coast AQMD emission
factor studies contained in Table 4-2. Both sets of emission factors were generally of poor quality and thus
were given a D rating based on the criteria discussed above. The emission factors from these studies are not
presented in the AP-42 section, but the South Coast AQMD study provides some valuable information on
"relative dustiness" (the amount of PM emitted by the various blast media) of several abrasives. The study
indicates that total PM emissions from abrasive blasting using grit are about 24 percent of total PM
emissions from abrasive blasting with sand. The study also indicates that total PM emissions from abrasive
blasting using shot are about 10 percent of total PM emissions from abrasive blasting with sand. This
information is presented in the text of the AP-42 section.
With regard to Table 4-3, only two data sets were identified which address control efficiency applied
to abrasive blasting operations. Both data sets were found to be extremely limited in scope and of poor
quality. As with the data for uncontrolled emissions, documentation of process operation was nonexistent in
both cases. However, the control efficiencies presented in these documents are discussed in the AP-42
section.
Table 4-4 provides an overall summary of the particulate emission factors developed in the study by
Kinsey, et al. As shown in Table 4-4, the emission factors for total PM tend to increase with wind speed for
each of the three types of mild steel surfaces blasted. Because the emissions contained no condensible
fraction, the total PM was collected entirely as "filterable" PM. The emission factors for PM-10, on the other
hand, show a tendency to decrease when the wind speed exceeds 10 mph. No substantial difference in
particulate emissions was observed, however, by either the type of surface cleaned or coating removed by the
abrasive.
The emission factors for five HAP metals and Fe are summarized in Tables 4-5, 4-6, and 4-7 for the
total PM, PM-10, and PM-2.5 particle size fractions, respectively. Except for Fe, these emission factors are
of the order of 10~6 kg per kg of sand. Five other HAP metals (As, Be, Co, Sb, and Se) were generally not
detected above blank levels.
4.3 DEVELOPMENT OF CANDIDATE EMISSION FACTORS
Based primarily on lack of documentation of the abrasive blasting process operation associated with
most of the tests summarized in Tables 4-2 and 4-3 (as noted above), only References 1 and 6 were used for
developing candidate PM emission factors. Reference 1 addresses only silica sand as a blasting medium, and
Reference 6 quantifies fabric filter-controlled PM emissions from blasting with garnet.
Regarding overall PM emissions from the Reference 1 abrasive blasting tests, no significant
dependence on the surface condition of the mild steel target panels was observed. Moreover, only the factors
for total PM emissions showed a consistent dependence on wind speed.
The candidate emission factors for PM-10 and PM-2.5 were derived (using Reference 1 data) as
simple averages of the results from the sand blasting of the three target panels, as shown in Table 4-8. The
candidate emission factors for total PM were differentiated by wind speed, as shown in Table 4-9.
4-7
-------
TABLE 4-4. SUMMARY OF PM TEST DATA FROM REFERENCE la
Operating
condition
Clean surface
5 mph
lOmph
15 mph
Test
runs
17/18
9/10
23/24
Average emission factor
Painted surface
5 mph
10 mph
15 mph
15/16
7/8
21/22
Average emission factor
Oxidized surface
5 mph
10 mph
15 mph
19/20
11/12
25/26
Average emission factor
Total PM
emission factor,
kg/kg sand
0.029
0.068
0.092
0.063
0.027
0.070
0.091
0.063
0.025
0.026
0.089
0.047
PM-10 emission
factor,
kg/kg sandb
0.017
0.0081
0.0045
0.0099
0.0059
0.052
0.0091
0.022
0.0057
0.014
0.0030
0.0074
PM-2.5
emission
factor,
kg/kg sandc
0.0024
0.0022
0.00090
0.0018
0.0010
0.00086
0.0013
0.0011
0.0018
0.0011
0.00026
0.0011
Result of mass
balance, %
closured
100
95
86
99
98
79
100
100
82
aAll results to two significant figures. Sand blasting only. Data are A-rated.
bParticles < 10 um in aerodynamic diameter (equivalent unit density spheres).
cParticles <2.5 um in aerodynamic diameter (equivalent unit density spheres).
n . ,
°Percent closure =
total sand recovered + total particulate emissions
= - - - -- - - - =
-, - -j- - -,
total sand fed to tunnel
, „ „
=100
4-8
-------
TABLE 4-5. SUMMARY OF EMISSION FACTORS FOR PM METALS
Operating condition
Test run
Total emission factor, kg/kg sand
Cadmium
Chromium
Iron
Manganese
Nickel
Lead
Clean surface
5 mph
lOmph
15 mph
Average emission factor
17/18
9/10
23/24
1.8e-06
7.0e-07
1.8e-06
1.4e-06
2.5e-06
6.5e-06
9.6e-06
6.2e-06
2.8e-04
5.1e-04
4.2e-04
4.0e-04
1.5e-06
2.9e-06
2.3e-06
2.3e-06
2.0e-06
4.9e-06
8.0e-06
5.0e-06
1.8e-06
1.3e-06
3.9e-06
2.4e-06
Painted surface
5 mph
10 mph
15 mph
Average emission factor
15/16
7/8
21/22
9.5e-07
l.le-06
6.3e-06
2.8e-06
4.3e-06
8.7e-06
1.9e-05
l.le-05
2.9e-04
3.5e-04
5.1e-04
3.8e-04
2.0e-06
4.0e-06
4.0e-06
3.3e-06
2.0e-06
4.7e-06
2.7e-05
l.le-05
7.1e-06
1.4e-05
2.0e-05
1.4e-05
Oxidized surface
5 mph
10 mph
15 mph
Average emission factor
19/20
11/12
25/26
6.4e-07
1.2e-06
1.6e-06
l.le-06
1.4e-06
5.2e-06
7.2e-06
4.6e-06
6.2e-04
1.6e-03
1.3e-03
1.2e-03
4.2e-06
1.2e-05
4.5e-06
7.1e-06
1.3e-06
7.1e-06
8.3e-06
5.5e-06
1.6e-05
7.8e-06
2.3e-05
1.5e-05
TABLE 4-6. SUMMARY OF EMISSION FACTORS FOR PM-10 METALS
Operating condition
Test run
PM-10 emission factor, kg/kg sand
Cadmium
Chromium
Iron
Manganese
Nickel
Lead
Clean surface
5 mph
10 mph
15 mph
Average emission factor
17/18
9/10
23/24
1.8e-06
a
1.3e-06
a
2.4e-06
6.4e-06
9.5e-06
6.1e-06
2.1e-04
3.1e-04
2.7e-04
2.6e-04
1.3e-06
2.1e-06
1.6e-06
1.7e-06
2.0e-06
4.4e-06
7.6e-06
4.7e-06
1.8e-06
1.3e-06
3.9e-06
2.3e-06
Painted surface
5 mph
10 mph
15 mph
Average emission factor
15/16
7/8
21/22
4.8e-07
a
2.9e-06
a
4.0e-06
8.0e-06
1.8e-05
6.1e-06
1.8e-04
2.8e-04
3.0e-04
2.6e-04
1.4e-06
3.2e-06
3.0e-06
1.7e-06
1.9e-06
4.2e-06
2.6e-05
4.7e-06
3.5e-06
l.Oe-05
7.9e-06
2.3e-06
Oxidized surface
5 mph
10 mph
15 mph
Average emission factor
19/20
11/12
25/26
3.7e-7
a
2.2e-07
a
1.4e-06
5.1e-06
6.9e-06
4.5e-06
3.8e-04
8.2e-04
4.8e-04
5.6e-04
2.4e-06
6.6e-06
2.0e-06
3.7e-06
1.2e-06
6.3e-06
7.8e-06
5.1e-06
7.0e-06
5.6e-06
8.4e-06
7.0e-06
aCadmium was not detected in any of the particle sizing fractions and therefore the calculations could not
be performed.
4-9
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TABLE 4-7. SUMMARY OF EMISSION FACTORS FOR PM-2.5 METALS
Operating condition
Test run
PM-2.5 emission factor, kg/kg sand
Cadmium
Chromium
Iron
Manganese
Nickel
Lead
Clean surface
5 mph
lOmph
15 mph
Average emission factor
17/18
9/10
23/24
1.4e-06
a
8.0e-07
a
1.5e-06
3.3e-06
5.4e-06
3.4e-06
l.le-04
2.0e-04
1.8e-04
1.7e-04
1.5e-07
2.4e-07
7.0e-08
1.5e-07
l.le-06
1.6e-06
3.0e-06
1.9e-06
l.le-06
1.2e-06
3.9e-06
2.1e-06
Painted surface
5 mph
10 mph
15 mph
Average emission factor
15/16
7/8
21/22
2.1e-07
a
7.6e-08
a
2.1e-06
4.0e-06
7.4e-06
4.5e-06
l.Oe-04
1.6e-04
1.5e-04
1.4e-04
2.9e-06
1.2e-06
1.2e-07
5.4e-07
8.6e-07
1.5e-06
8.1e-06
3.5e-06
2.8e-06
5.6e-06
6.3e-06
4.9e-06
Oxidized surface
5 mph
10 mph
15 mph
Average emission factor
19/20
11/12
25/26
3.1e-07
a
3.1e-09
a
3.2e-07
3.0e-06
3.7e-06
2.4e-06
1.4e-04
1.9e-04
2.2e-04
1.8e-04
4.2e-07
2.4e-07
8.6e-08
2.5e-07
4.2e-07
3.4e-06
4.0e-06
2.6e-06
4.5e-06
4.9e-06
6.6e-06
5.3e-06
aCadmium was not detected in any of the particle sizing fractions and therefore the calculations could not
be performed.
TABLE 4-8. CANDIDATE PM-10 AND PM-2.5 EMISSION FACTORS
Surface
Precleaned
Painted
Oxidized
Average
PM emission factors, kg/kg sand
PM-10
0.0099
0.022
0.0074
0.013
PM-2.5
0.0018
0.0011
0.0011
0.0013
4-10
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TABLE 4-9. CANDIDATE TOTAL PM EMISSION FACTORS DIFFERENTIATED
BY WIND SPEED
Wind speed
5 mph
lOmph
15 mph
Emission factor (kg/kg sand) by surface type
Precleaned
0.029
0.068
0.092
Painted
0.027
0.070
0.091
Oxidized
0.025
0.026
0.089
Average
0.027
0.055
0.091
All of these candidate emission factors are assigned E ratings because they are based on data from a single
study.
Data from Reference 6 were used to calculate an emission factor for fabric filter-controlled abrasive
(garnet) blasting. This emission factor is shown in Table 4-10.
TABLE 4-10. CANDIDATE EMISSION FACTOR FOR GARNET BLASTING
Source
Enclosed blasting of unspecified
metal parts with 30/40 mesh garnet
Control
Fabric filter
No. of
tests
1
EMISSION
FACTOR
RATING
E
Total PM
emission factor,
kg/kg of abrasive
used
0.00069
Reference
No.
6
Because the emissions of HAP metals are strongly dependent on the target material composition and
its surface condition, no specific candidate emission factors are proposed.
4.4 REFERENCES FOR SECTION 4
1. J. S. Kinsey, Assessment of Outdoor Abrasive Blasting, Interim Report, EPA Contract No. 68-02-4395,
Work Assignment No. 29, U. S. Environmental Protection Agency, Research Triangle Park, NC,
September 11, 1989.
2. NEESA 2-161. Paniculate and Chromium Emission Testing at Plastic Media Blasting Facility,
BLDG 25, Naval Aviation Depot, Naval Air Station, Alameda, CA, Naval Energy and Environmental
Support Activity, PortHueneme, CA, May 1990.
3. Determination of Paniculate Emission Rates & Baghouse Removal Efficiency, Hamilton Foundry,
Harrison, Ohio, K&B Design, Inc., Cincinnati, OH, September 3, 1991.
4. Written Communication from D. Borda, The Hamilton Foundry & Machine Co., Harrison, OH, to L.
Gruber, Southwestern Ohio Air Pollution Control Agency, Cincinnati, OH, November 27, 1990.
5. Summary of Source Test Results, Hunter Schlesser Sandblasting, San Leonardo, CA, Bay Area Air
Quality Management District, San Francisco, CA, March 3, 1993.
4-11
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6. Summary of Source Test Results, Poly Engineering, Richmond, CA, Bay Area Air Quality
Management District, San Francisco, CA, November 19, 1990.
7. Samimi, B., "Silica Dust in Sandblasting Operations," Ph.D. Thesis, Tulane University, 1973.
8. Samimi, B., et al., "Dust Sampling Results at a Sandblasting Yard Using Stan-Blast in the New Orleans
Region: A Preliminary Report," NIOSH-00036278, New Orleans, LA, 1974.
9. Samimi, B., et al., "The Efficiency of Protective Hoods Used by Sandblasters to Reduce Silica Dust
Exposure," Am. Indus. Hyg. Assn. J., 36(2), February 1975.
10. Landrigan, P. J., et al., "Health Hazard Evaluation Report on the Tobin-Mystic River Bridge,"
TA80-099-859, NIOSH Report to City Boston Department of Health and Hospitals, Boston, MA,
July 25, 1980.
11. Bareford, P. E., and F. A. Record, "Air Monitoring at the Bourne Bridge Cape Cod Canal,
Massachusetts," Final Report, Contract No. DACW 33-79-C-0126, U.S. Army Corps of Engineers,
New England Division, Waltham, MA, January 1982.
12. Beddows, N. A., "Lead Hazards and How to Control Them," Natl. Safety News, 128(6), December
1983.
13. Lehner, E., et al., Memo to D. M. Moline, Department of Public Utilities, Division of Environmental
Services, City of Toledo, OH, January 31, 1985.
14. WhiteMetal, Inc., "Protecting Our Environment with the Jet Stripper," Houston, TX, June 1987.
15. South Coast Air Quality Management District, "Section 2: Unconfmed Abrasive Blasting," Draft
Document, El Monte, CA, September 8, 1988.
4-12
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5. PROPOSED AP-42 SECTION 13.2.6
The following pages contain the proposed new AP-42 section for abrasive blasting as it would
actually appear in the document.
5-1
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