Ann. Occup. Hyg., pp. 1–7

Published by Oxford University Press

on behalf of the British Occupational Hygiene Society

doi:10.1093/annhyg/mem069

Received 11 December 2006; in final form 17 December 2007

*Author to whom correspondence should be addressed.

Tel: 412-386-6689; fax: 412-386-4917; e-mail: jdv1@cdc.gov

1 of 7

Field Measurement of Diesel Particulate Matter 

Emissions 

JON C. VOLKWEIN1 *, STEVEN E. MISCHLER1

1

Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health,

Pittsburgh Research Laboratory, PO Box 18070, Pittsburgh, PA 15236, USA;

, BRIAN DAVIES2 

2

School of Health

Sciences, University of Wollongong, NSW 2522, Australia;

and 

CLIVE ELLIS3† 

3

NSW Department of Mineral Resources,

PO Box 76, Lidcombe, NSW 2141, Australia

y

Now retired. 

A primary means to reduce environmental levels of diesel particulate matter (DPM) exposure 

to miners is to reduce the amount of DPM emission from the engine. A quick and economic 

method to estimate engine particulate emission levels has been developed. The method relies 

on the measurement of pressure increase across a filter element that is briefly used to collect 

a DPM sample directly from the engine exhaust. The method has been refined with the inclusion of an annular aqueous denuder to the tube which permits dry filter samples to be obtained 

without addition of dilution air. Tailpipe filter samples may then be directly collected in hot and 

water-supersaturated exhaust gas flows from water bath-cooled coal mine engines without the 

need for dilution air. 

Measurement of a differential pressure (DP) increase with time has been related to the mass 

of elemental carbon (EC) on the filter. Results for laboratory and field measurements of the 

method showed agreement between DP increase and EC collected on the filter with R2 values 

>0.86. The relative standard deviation from replicate samples of DP and EC was 0.16 and 0.11, 

respectively. The method may also have applications beyond mining, where qualitative evaluation of engine emissions is desirable to determine if engine or control technology maintenance 

may be required. 

INTRODUCTION 

Diesel engines are efficient and economical power 

sources for mobile equipment used by the underground mining industry. Increasing the size of mining equipment to achieve economies of scale has 

led to larger engines with increasing exhaust gas volumes. The health effects of most of the inorganic gaseous components of the exhaust are well known. In 

particular, the carbon monoxide emission levels of 

diesel vehicles in the US are required to be monitored 

weekly by a qualified person in the mine (CFR 30, 

1978). 

The particulate fraction of diesel exhaust, on the 

other hand, is much more complex in nature and 

the suspected health effects are not well understood. 

It is generally accepted that human exposure to diesel 

particulate matter (DPM) should be minimized because of the designation of DPM as a suspected carcinogen (NIOSH, 1988). Nevertheless, at this time, 

control technology and monitoring of DPM levels 

in underground work environments are quite new 

and governments and industry worldwide are striving 

to set acceptable limits and monitoring regimes to 

protect the health of workers. 

Exposure of underground workers to DPM can be 

controlled using three basic approaches. The first approach would be to reduce the DPM emissions at the 

source by implementing a variety of techniques such 

as engine maintenance, exhaust filtration and use of 

reformulated fuels. The second approach would be 

to assure adequate volumes of dilution air. The third 

method would be to administratively limit the 

number and horsepower of vehicles allowed within 

a given volume of ventilation air (Schnakenberg 
2 of 7 J. C. Volkwein et al.

and Bugarski, 2002). Simple methods to know the 

emission levels would be useful to help minimize 

exposure of workers to DPM. 

Over time, engine use leads to component wear 

and changing emission levels. Mines, therefore, are 

typically mandated to measure and keep records of 

gas emission levels on a weekly basis. Particulate 

levels could be monitored on a similar basis. Current 

techniques to monitor raw exhaust gas particulate 

levels from engines rely on laboratory quality gravimetric measurements of diluted fractions of the 

exhaust gas stream (ASTM Standard, 2002). Similar 

quantitative measurements in the field cannot be 

done without complex instrumentation and extreme 

control of experimental variables. 

Field-worthy techniques to provide a qualitative 

estimate of DPM emissions each have their limitations. The Bosch smoke method is an optical 

transmission method whose results vary with load 

and gives variable results in water-supersaturated 

environments. The ECOM (ECOM America Ltd, 

Gainsville, GA, USA) gas analyzer has a built-in 

filter that blackens with particulate loading. Interpretation of the smoke dot on the filter requires 

a subjective judgment on the blackness of the filter. Opacity and light-scattering monitors do not 

work well in water-condensing environments since 

the water droplets affect the measurement. Some 

efforts to use a minidiluter with the optical techniques have met with some success but require careful attention to the dilution system. Another field 

technique that has been used involved a large 

laboratory-type elemental carbon (EC) analyzer 

mounted in a trailer (Davies, 2000); however, because of the size and cost, it is not truly a field 

type of instrument. What would be useful is a 

small simple device that the mechanics could 

use during a gas emission-level check to also determine when an engine begins to emit excessive 

levels of DPM. 

One of the challenges of sampling combustion 

aerosols is the changing nature of the particulate 

matter as it cools and condenses into the atmosphere. The presence of water as a product of combustion normally precludes collecting aerosols on 

filters unless heated sampling lines or a quantitative 

volume of dilution air is provided. The ability to 

collect a dry filter sample in raw exhaust gas is 

even more difficult in some engines used in underground coal mining because of the requirement to 

pass exhaust gas through a water trap to cool and 

thus prevent possible ignition of mine gas and coal 

dust. 

The chemical and physical complexity of DPM 

further complicates measurement techniques. The 

National Institute for Occupational Safety and 

Health (NIOSH) recommends that EC be the marker 

for DPM as analyzed by NIOSH Analytical Method 

5040 (Birch and Cary, 1996). EC has few interfering 

chemical species and is the major component of 

the chemically complex DPM produced by diesel 

engines. While no one parameter totally describes 

DPM from an analytical point of view, EC, or a technique that tracks EC, gives a result that is as least as 

accurate as our current knowledge of the health 

effects of DPM (NIOSH, 1988). 

In an effort to find a mine-worthy particulate 

monitor that mine mechanics can routinely use to 

monitor the particulate emission levels of their 

mining equipment, the Coal Services Health and 

Safety Trust in New South Wales, Australia, 

funded a project to measure the effectiveness of various approaches to tailpipe particulate monitoring. 

Through this effort, the New South Wales Department of Minerals Resources funded the Centers 

for Disease Control and Prevention/NIOSH/ 

Pittsburgh Research Laboratory (PRL) to test 

a newly developed differential pressure (DP)-based 

diesel particulate tailpipe monitor. Testing was conducted in Londonderry’s TestSafe Australia diesel 

dynamometer research laboratory and at various diesel engine shops at underground mines in Australia. 

The overall study compared various potential portable engine tailpipe monitor devices with the standard American Society for Testing and Materials 

(ASTM) laboratory particulate measurement instruments whose results will be published elsewhere. 

The Coal Services Report (2004) compared the 

Diesel Detective to the full-scale dilution tunnel test 

and concluded that the Diesel Detective is suitable 

for measuring DPM from raw diesel exhaust. 

The PRL tailpipe monitor system described in this 

work was developed through a cooperative research 

and development agreement between SKC, Inc. 

(Eighty Four, PA, USA), and the NIOSH/PRL. The 

development was an extension of a Dust Dosimeter 

that used similar principles to provide a qualitative 

assessment of workplace-respirable dust levels 

(Volkwein et al., 2000; Page et al., 2000). This paper 

describes the relationship of near-real-time DP 

measurements with the amount of EC deposited on 

a filter collected from raw diesel tailpipe exhaust. 

This method is suitable for periodic measurements 

of DPM emission in field conditions. The results 

can be used to determine when servicing is necessary 

to minimize DPM emissions or to determine if a particular engine exceeds normal operating emission 

levels in coal mine service. Initial laboratory results 

from NIOSH, results of the Australian laboratory 

and field testing are presented. A previously presented paper described similar results when using 

this technique for hot exhaust gas streams exceeding 

100°C (Mischler et al., 2005). While the focus of this 

paper has been toward mining applications, there are 

considerable applications of tailpipe monitoring in 

over-the-road and off-road diesel emission monitoring. 
DESCRIPTION OF THE DEVICE 

This device, known as the Diesel Detective uses 

two components to determine tailpipe DPM levels. 

The first component is a detector tube that is placed 

directly into the exhaust tailpipe and contains a 

filter, holder and aqueous denuder for control of 

moisture on the filter. The second component is 

a handheld programmable pump that is connected 

to the detector tube. This pump automatically takes 

a predetermined sample and calculates the difference in pressure across the filter in the tube from 

the beginning to the end of a sample. The pump 

currently reports the DP but, if properly calibrated, 

can provide an estimate of the EC present on the 

filter. 

Detector tube

The detector tube is used to sample the exhaust 

from an engine used in coal mines, where exhaust 

is passed through a baffled, water-filled tank, to cool 

and prevent ignitions of mine gases. These scrubberequipped vehicles normally have a water vaporsaturated tailpipe temperature of 60°C. Similar 

principles apply to detector tubes sampling hot 

untreated exhaust streams with the exception that 

no desiccant is needed, materials that can tolerate 

higher temperatures are required and temperature 

measurement for correction of gas volume flow rate 

is recommended. 

The detector tubes for use with scrubbers were 

constructed from commercially available copper 

tubing [9.2 cm long, 9.5 mm outer diameter (OD) 

and 7.6 mm inner diameter (ID)] and nominal 

3/8-in. ( 10 mm) brass fittings. The brass fittings 

were counterbored to create a square-edge shoulder 

to support a stainless steel backup screen and glass 

fiber filter compatible with the NIOSH 5040 carbon 

analysis. A 9.5-mm OD and 6.4-mm ID precision 

stainless steel washer, placed on the front of the filter, precisely defined the area where the DPM was 

deposited and the area over which the filter pressure 

difference occurred. A high-temperature O-ring 

sealed the area between the washer and copper tube. 

An annular aqueous denuder within the copper tube 

consisted of a 7-cm-long cylinder of 5 A ̊ mole sieve 

desiccant rings with outer and inner diameters of 

7.5 and 4.8 mm, respectively. These were used to 

remove moisture before the DPM deposited on the 

filter. The denuder design permits an unobstructed 

path for particulate from the inlet to the filter. Previous testing of this design showed that a flow of 

saturated steam would be absorbed by the desiccant 

for a period of 2 min before moisture breakthrough 

occurred. The filter may then be removed from 

the tube and sent to a laboratory for analysis of the 

EC. Figure 1 shows the major components of the 

detector tube. 

Fig. 1. Principal components of detector tube. 

P ® ocket Pump

Early stages of testing used a commercially avail­ ® able SKC Pocket Pump (SKC Inc.). This is a variable low flow rate pump with an integral pressure 

gauge that monitors filter back pressure. The researcher used a stopwatch to time an initial 20-s period of filter stabilization in the exhaust stream, 

followed by manually observing an initial pressure, 

timing a 60-s sample period, quickly observing a final 

pressure and removing the probe from the exhaust. 

Diesel detective pump

The Diesel Detective Pump was developed to 

simplify the measurement method. It is based on ® the Pocket Pump design but operates at a fixed 

volumetric flow-controlled rate of 250 ml min-1

. 

This new pump also includes improved pressure sensors, improved memory capacity, new programing, 

automated sampling and rugged case for mine 

environments. 

The sample air (less DPM on the filter) travels 

from the detector tube through a copper cooling coil 

where the temperature is reduced to ambient levels. 

Volumetric flow rate is maintained using a pressurebased flow control device that adjusts pump speed to 

maintain constant volumetric flow. 

The Diesel Detective Pump is unique in that it may 

be programed to take an automated 80-s sample. The 

first 20 s is used to acclimatize the filter to the temperature of the exhaust. The pump then marks the 

initial pressure and continues to sample for an additional 60 s. At the 80-s end point, the pump electronics subtract the initial pressure from the final 

pressure, display the DP and record the measurement 

history in memory for later retrieval and analysis. 

METHODS 

Initial laboratory testing

The first testing of the prototype of the Diesel 

Detective system took place at the NIOSH/PRL. A 

41-kW Isuzu diesel engine was used on a portable 

laboratory dynamometer with the exhaust run 

through a water bath scrubber commonly used in 

mines. The apparatus is shown in Fig. 2. The engine 

was run at steady state in each of the eight-mode 
4 of 7 J. C. Volkwein et al.

Mine Safety and Health Administration (MSHA) 

diesel engine test points (CFR 30, 1996). For each 

mode, testing began after a warm-up period and after 

temperatures of the exhaust gas stream became stable. Three sequential tailpipe DPM measurements 

were made in each mode. Tests were conducted using ® the Pocket Pump and a stopwatch to measure the 

rate of pressure increase per minute across the filter. 

The filters were then analyzed by NIOSH Method 

5040 for EC mass (NIOSH, 1999). The only modifications to the published method were that the entire 

filter rather than a punched sample of the larger filter 

was used for the analysis and the appropriate area 

calculations were used. The concentration of EC 

was then calculated using the total pump run time 

of 80 s and the flow rate of 250 ml min -1

. 

Fig. 2. Mobile engine dynamometer with exhaust of Isuzu C240 engine connected to stainless steel water bath in 

foreground used for preliminary laboratory testing at NIOSH/PRL. 

Australian laboratory testing

Based on the initial NIOSH laboratory results, 

more extensive testing was conducted at the TestSafe, Londonderry research facility near Sydney, 

Australia. The facility uses a state-of-the-art dynamometer with a full-flow exhaust gas dilution system 

to evaluate both gaseous and particulate emissions. 

Details of the testing were devised by a committee 

consisting of engineers and scientists from the mining industry, engine manufacturers and the New 

South Wales Department of Mineral Resources 

(Mine Safety Technical Services, 2004). Testing 

was done by researchers from several organizations 

coordinated by the Department. 

The Diesel Detective and a number of other tailpipe measurement techniques were evaluated in 

parallel at the Londonderry facility. Three engines 

commonly used by the underground mining industry 

were evaluated: a Caterpillar 3306 (72 kW) and 

a KIA (37 kW), both naturally aspirated engines, 

and a turbocharged Caterpillar 3126 (133 kW). The 

exhaust from each of the engines was passed through 

a water bath-cooling/scrubber system. DPM samples 

were taken with the detector tubes and Pocket ® Pump directly from the undiluted cooled exhaust 

gas portion of the test apparatus. The Diesel Detective tubes with filters in place were then sent to 

NIOSH/PRL for EC analysis using NIOSH Method 

5040. 

While the Pocket Pump DP versus the EC mass ®

collected on the same filter was being determined, 

a full-scale dilution filter sample was also collected 

and weighed. This enabled an analytically determined EC measurement from the undiluted exhaust 

to be compared with the diluted gravimetric sample 

collected according to the ASTM Standard (2002). 

Thus, the determination of the Diesel Detective EC 

and DP can be compared to the laboratory reference 

mass. In turn, field measurement of DP alone can be 

compared to analytically determined EC, a recognized surrogate of DPM. The calculated DP was 

manually corrected for temperature using Henry’s 

law. Use of the engine dynamometer allowed us to 

set and monitor steady-state conditions, which enabled triplicate sequential samples to be taken. In 

place of a standardized engine mode test that used 

fixed points, this test protocol permitted engine conditions to be adjusted to produce a nearly linear increase in DPM production from idle to full load. 
Field measurement of DPM emissions 5 of 7

Field measurements

The Diesel Detective Pump was used to conduct 

field sampling at five mines in New South Wales, 

Australia, in June and July, 2004. A total of 44 samples were collected from the water-scrubbed exhaust 

of 21 different machines. The DP reading from the 

Diesel Detective Pump display was recorded and 

the sample tubes were sent to NIOSH/PRL for 

NIOSH 5040 analysis. Because DP varied with load, 

it was essential that a consistent procedure be used to 

create similar load conditions for each test. 

Field test procedures consisted of bringing the 

mine machines’ engines to operating temperature 

then, while the machine was at idle, the detector tube 

was inserted into the tailpipe while simultaneously 

starting the Diesel Detective Pump sample. An initial 

pump pressure was recorded 20 s into the measurement. About 30 s into the sample, a torque converter 

stall condition was created by accelerating the engine 

while loading either the vehicle’s transmission or hydraulic system with a dead load. This loaded condition was held for 20 s and the engine was brought 

back to idle until the Diesel Detective Pump cycle 

was completed—at a time equal to 80 s. Not all machines could achieve torque converter stall, but some 

form of acceleration and load was substituted in 

those cases. An important part of this test procedure 

was that the initial pressure measurement at 20 s 

and final pressure measurement at 80 s be taken at 

approximately the same engine RPM. The DP per 

minute reported by the Diesel Detective Pump was 

recorded, and the tubes were sent to NIOSH/PRL, 

where filters were analyzed for EC content using 

NIOSH 5040 analysis. 

Statistical analysis

Data were examined using regression analysis to 

determine the coefficient of determination R2

, of

the DP and EC determinations from each test group. 

The limit of detection and limit of quantification 

were determined from the standard deviations 

(SDs) of the triplicate blank filter measurements. 

RESULTS AND DISCUSSION 

NIOSH Laboratory

The scatter plot of DP versus EC that resulted from 

the eight-point MSHA test is shown in Fig. 3. 

Fig. 3. Scatter plot of preliminary portable dynamometer 

water bath data following MSHA eight-point testing 

protocol (1 in. water-gauge 5 249 Pa). 

Because the instrument reports the pressure as inches 

of water (where 1 in. H2O 5 249 Pa) that notation 

will be used in all figures. In general, the correlation 

between DP and EC was linear. However, Test Mode 

5 called for lugging the engine under full load at an 

intermediate speed and resulted in the triplicate 

measurements showing a large concentration of EC 

and corresponding high DP. The exact functional 

form of this relationship was difficult to define because of the lack of data between the lowest and 

highest levels of emissions. Based on these preliminary results, however, it was apparent that the DP 

measurement alone had potential to predict EC levels 

on the filter. More detailed testing was required. 

Australian laboratory testing

Detailed results from the Londonderry testing 

are reported in Coal Services report 04/0884 

(2004). A subset of the data is presented in Fig. 4. 

Fig. 4. Laboratory dynamometer-diluted mass concentration
 


compared to undiluted DP and EC from the Diesel
 


Detective (dilution tunnel filter concentrations courtesy
 


of Coal Services 2004) (1 in. water-gauge 5 249 Pa).
 


DP: upper line and open squares; EC: lower line and diamonds.
 


These results show the undiluted exhaust EC concentrations measured by the Diesel Detective filters and 

corresponding diluted exhaust diesel particulate mass 

measurements. These data are from laboratory tests 

of three engines commonly used in mines and all using water bath scrubbing. The slope of the regression 

of 0.63 is in agreement with previous data which 

indicate that EC composes 0.6–0.8 of the total 

DPM of raw diesel emissions (Birch and Cary, 1996). 

The relationship between DP and dilution tunnel filter concentration shows similar correlation to that of 
6 of 7 J. C. Volkwein et al.

EC. Thus, the measurement of DP in the field would 

be expected to relate to laboratory dilution tunnel 

mass measurements. 

Figure 5 shows the coefficient of determination 

between DP and EC from the undiluted exhaust in 

the Londonderry Diesel Dynamometer Laboratory 

testing. 

Fig. 5. Laboratory dynamometer results of Diesel Detective.
 


Error bars represent 1 SD (1 in. water-gauge 5 249 Pa).
 


Exhaust gas temperatures were 60°C at

the filter and 25°C at the pump. The data were well 

distributed over a range of EC concentration levels 

from 8 to 110 mg m -3 of EC. The data have an 

R2 value of 0.91. 

The error bars on Fig. 5 represent 1 SD and are an 

estimate of the precision of the triplicate measurements of both the DP and EC measurements. Because 

the DP and EC results are from the same filter, systematic errors in sampling are likely to result in similar SDs. A large SD appearing in one parameter and 

not in the other is most likely a result from a measurement or analysis error of that parameter. 

For the laboratory experiments, the limit of detection, as defined by the mean filter blank mass value 

plus 3 SDs for EC, was 0.50 mg m -3

. The limit of 

quantification, defined by the mean filter blank mass 

plus 10 SDs for EC, was 1.30 mg m -3

. The laboratory relative SD of the triplicate DP and EC measurements was 0.15 and 0.11, respectively. 

Field measurements

Field results using the Diesel Detective Pump are 

shown in Fig. 6. 

Fig. 6. Field results from Australian mine equipment 

These results have a somewhat (1 in. water-gauge 5 249 Pa). 

improved R2 value over the laboratory data that used 

the Pocket Pump. This may be partially due to the 

improved pressure transducer and electronics of 

the newer Diesel Detective Pump. Four of the initial 

samples were voided during the analysis process 

due to obvious water spots on the filter. The source 

of the water was attributed to samplers ingesting 

a large stream of liquid water that water bath scrubbers occasionally emit. While the aqueous denuder 

works well at removing supersaturated water vapor, 

it can be overwhelmed by a significant stream of liquid water. Careful attention to probe placement can 

minimize this event. 

Field precision results were similar to the laboratory precision results. The field average precision estimated by the relative SD from 12 samples (ranging 

from 2 to 5 replicates) for DP and EC was 0.16 and 

0.11, respectively. Because the precision of the 

method determined with the Pocket Pump was similar to the precision based on the Diesel Detective 

Pump, the small difference in precision could not 

be attributed to the new pump design. 

Overall results

When data from the laboratory and field testing are 

combined in Fig. 7, the resulting R2 value drops 

slightly to 0.86, perhaps a reflection of the Pocket 

Pump versus the Diesel Detective Pump. 

Fig. 7. Combined laboratory and field data with –95% 

confidence limits (1 in. water-gauge 5 249 Pa). 

Note the y

intercept of 6.54 mg m -3 EC is interpreted as part 

of the bias of the technique which is subject to further 

investigation. The regression equation in Fig. 7 was 

calculated from Sigma Plot software which enables 

calculation of confidence intervals. Inclusion of the 

–95% confidence limits shows a number of data 

points outside of this limit, suggesting that the Diesel 

Detective is best suited as a survey quality measurement of engine particulate emission. If no design 
Field measurement of DPM emissions 7 of 7

changes occur with the filter holder, the data in Fig. 7 

could be used to create a calibration factor for the 

pump to convert from DP rate to EC concentration. 

Any design change to the filter holder would require 

recalibration since the measurements are sensitive to 

the precise area of the filter sample. In the interim, 

the DP reading reported by the device can always 

be used as a relative measurement of engine EC 

emission. 

Given the wide variety of emission characteristics 

of diesel engines and the difficulty of establishing an 

accurate correlation of any measurement method 

in the field, the comparison of an engine to itself is 

perhaps the best solution. Monitoring the emission 

history or the pre- and post-maintenance of a particular engine would then indicate the appropriate time 

for maintenance to control DPM. Table 1 shows the 

results of a pre- and post-maintenance test of some 

engines using the Diesel Detective.

Table 1. Example of pre- and postmaintenance testing 

Vehicle Premaintenance Postmaintenance Maintenance 

type in H2O in H2O performed 

Eimco 13.9 4.1		 New injectors 

SMV 5076 5.9 3.2		 Retard timing, 

cleaned intake 

system, 

reduced fuel 

PJB 107 17.5 6.4		 Cleaned intake, 

reduced fuel 

PJB 15 12.5 5.9		 Changed air 

cleaner 

 Another suggested way to use this instrument would be to survey 

the fleet of engines in regular mine use to establish 

a baseline, perhaps by engine type, and to then select 

a target maximum pressure allowed for a specific vehicle type before maintenance is required. This 

would, in effect, enable mechanics to target repairs 

toward the worst DPM-producing engines, thereby 

providing the largest reduction in ambient DPM 

levels per maintenance hour. 

CONCLUSIONS 

A direct method to measure tailpipe DPM emissions can be made by placing a filter directly into 

the hot and even extremely wet exhaust gas flow 

without need for dilution. The inclusion of an annular 

aqueous denuder to the tube permits dry filter samples to be obtained. A rise in DP in the tailpipe filter 

samples correlates well with corresponding EC on 

those filters which is a measure of the engines 

DPM emission. Because EC is the predominate component of the black soot emitted from diesel engines, 

using this DP method, data from this instrument can 

help a mechanic immediately and clearly identify 

which engines in a vehicle fleet are producing EC 

at a greater rate than other engines. Focusing cleaning, tuning and maintenance on these high-emission 

engines will produce the greatest efficiency for the 

reduction of fleet DPM emissions. 

This technique offers a survey-type quality measurement of DPM. It provides an inexpensive, handheld and rugged device for everyday use in mines. 

Another version of the technique for hot exhausts 

that do not pass through a water bath scrubber may 

be used to spot-check DPM emissions on over-theroad vehicles. This approach would provide both immediate feedback on the relative emission of a vehicle 

and a filter sample for subsequent analysis of the 

results. Calibration of DP to EC concentration is 

certainly possible, but additional data are required 

before the accuracy of such a relationship can be 

determined. 

REFERENCES 

ASTM Standard. (2002) BS ISO 16183 (2002) Heavy duty engines. Measurement of gaseous emissions from raw exhaust 

gas and of particulate emissions using partial flow dilution 

systems under transient test conditions. New York: American 

National Standards Institute. 

Birch ME, Cary RA. (1996) Elemental carbon-based method 

for monitoring occupational exposures to particulate diesel 

exhaust. Aerosol Sci Technol; 25: 221–41. 

Mine Safety Technical Services, NSW Department of Primary 

Industries, Coal Services Health and Safety Trust. (2004) 

Ellis C, editor. Methods for measuring diesel particulate 

matter from underground mining equipment, Report 04/ 

0884. p. 133. Available at http://coalservices.hstrust.com. 

au/Files/Reports/DPI%20-%20Ellis%20-%202004%2020 

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(1978),‘‘Maintenance of diesel-powered equipment.’’ 

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‘‘Diesel engines intended for use in underground coal 

mines.’’ 

Davies B. (2000) Application of an elemental carbon analyser 

to the measurement of particulate levels from diesel vehicles, 

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Pty Ltd. 

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NIOSH. (1999) Elemental carbon (diesel particulate): method 

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classifier. Appl Occup Environ Hyg; 15: 561–8. 

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