IC 9467

INFORMATION CIRCULAR/2004

Department of Health and Human Services

Centers for Disease Control and Prevention

National Institute for Occupational Safety and Health

Analyses of Mobile Equipment Fires

for All U.S. Surface and Underground

Coal and Metal/Nonmetal Mining

Categories, 1990-1999
Information Circular 9467

Analyses of Mobile Equipment Fires for All U.S. Surface 

and Underground Coal and Metal/Nonmetal Mining 

Categories, 1990-1999

By Maria I. De Rosa

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES 

Public Health Service 

Centers for Disease Control and Prevention 

National Institute for Occupational Safety and Health 

Pittsburgh Research Laboratory 

Pittsburgh, PA 

January 2004
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DHHS (NIOSH) Publication No. 2004-105 

This document is the public domain and may be freely copied or reprinted. 

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Disclaimer: Mention of any company or product does not constitute endorsement by NIOSH. 
CONTENTS 

Page 

Abstract ................................................................................................................................................................... 1 

Introduction ................................................................................................................................................................... 2 

Methodologies................................................................................................................................................................. 2 

Mobile equipment data analysis for all coal mining categories ...................................................................................... 3 

Mobile equipment fires at surface coal mines ............................................................................................................ 3 

Mobile equipment fires at surface of underground coal mines................................................................................... 9 

Mobile equipment fires at coal preparation plants ..................................................................................................... 13 

Mobile equipment fires in underground coal mines ................................................................................................... 17 

Mobile equipment data analysis for all metal/nonmetal mining categories .................................................................... 22 

Mobile equipment fires at surface metal/nonmetal mines .......................................................................................... 22 

Mobile equipment fires at surface sand and gravel and stone mines.......................................................................... 26 

Mobile equipment fires at metal/nonmetal and stone mills........................................................................................ 31 

Mobile equipment fires in underground metal/nonmetal and stone mines................................................................. 36 

Summary of major mobile equipment fire and fire injury findings for all coal mining categories ................................. 42 

Summary of major mobile equipment fire and fire injury findings for all metal/nonmetal mining categories............... 46 

Conclusions ................................................................................................................................................................... 51 

Acknowledgment ............................................................................................................................................................ 51 

References ................................................................................................................................................................... 51 

ILLUSTRATIONS 

 1. Mobile equipment fires and injuries for surface coal mines by state, 1990-1999 ............................................... 4 

 2. Major variables for mobile equipment fires at surface coal mines, 1990-1999................................................... 4 

 3. Mobile equipment fires, injuries, risk rates, employees' working hours, and coal production (coal production 

 for surface and underground coal mines only) by time period for each coal mining category, 1900-1999... 8 

 4. Mobile equipment fires and injuries for surface of underground coal mines by state, 1990-1999...................... 11 

 5. Major variables for mobile equipment fires at surface of underground coal mines, 1990-1999......................... 12 

 6. Mobile equipment fires and injuries for coal preparation plants by state, 1990-1999......................................... 14 

 7. Major variables for mobile equipment fires at coal preparation plants, 1990-1999............................................ 16 

 8. Mobile equipment fires and injuries for underground coal mines by state, 1990-1999 ...................................... 18

 9. Major variables for mobile equipment fires in underground coal mines, 1990-1999.......................................... 18 

 10. Mobile equipment fires and injuries for surface metal/nonmetal mines by state, 1990-1999 ............................. 24 

 11. Major variables for mobile equipment fires at surface metal/nonmetal mines, 1990-1999................................. 24 

 12. Mobile equipment fires, injuries, risk rates, and employees' working hours by time period for each 

 metal/nonmetal mining category, 1990-1999 ................................................................................................. 28 

 13. Mobile equipment fires and injuries for surface sand and gravel and stone mines by state, 1990-1999............. 29 

 14. Major variables for mobile equipment fires at surface sand and gravel and stone mines, 1990-1999 ................ 29 

 15. Mobile equipment fires and injuries for metal/nonmetal and stone mills by state, 1990-1999........................... 33 

 16. Major variables for mobile equipment fires at metal/nonmetal and stone mills, 1990-1999 .............................. 33 

 17. Mobile equipment fires and injuries for underground metal/nonmetal and stone mines by state, 1990-1999 .... 37 

 18. Major variables for mobile equipment fires in underground metal/nonmetal and stone mines, 1990-1999 ....... 37 

 19. Mobile equipment fires, injuries, risk rates, employees' working hours, and coal production (coal production 

 for surface and underground coal mines only) for all coal mining categories by time period, 1990-1999..... 46 

 20. Mobile equipment fires, injuries, risk rates, and employees' working hours for all metal/nonmetal mining 

 categories by time period, 1990-1999 ........................................................................................................... 48 

TABLES 

 1. Number of mobile equipment fires, injuries, and risk rates for surface coal mines by state, equipment 

 involved, coal production, and employees' working hours, 1990-1999.......................................................... 5 

 2. Number of mobile equipment fires, injuries, and risk rates for surface coal mines by time period, equipment 

 involved, activity, and employees' working hours, 1990-1999 ...................................................................... 6 

 3. Number of mobile equipment fires for surface coal mines by ignition source, equipment involved, and time 

 period, 1990-1999 .......................................................................................................................................... 6 
TABLES–Continued 

Page 

 4. Number of mobile equipment fires for surface coal mines by method of detection, equipment involved, 

 and time period, 1990-1999............................................................................................................................ 7 

 5. Number of mobile equipment fires for surface coal mines by suppression method, equipment involved, 

 and time period, 1990-1999............................................................................................................................ 8 

 6. Number of fire injuries per number of mobile equipment fires causing injuries and total fires at surface 

 coal mines by year, ignition source, equipment involved, and location, 1990-1999...................................... 10 

 7. Number of mobile equipment fires, injuries, and risk rates for surface of underground coal mines by state, 

 equipment involved, and employees' working hours, 1990-1999................................................................... 10 

 8. Number of mobile equipment fires, injuries, and risk rates for surface of underground coal mines by time 

 period, equipment involved, activity, and employees' working hours, 1990-1999......................................... 11 

 9. Number of mobile equipment fires for surface of underground coal mines by ignition source, equipment 

 involved, and time period, 1990-1999............................................................................................................ 12 

 10. Number of mobile equipment fires for surface of underground coal mines by method of detection, equipment 

 involved, and time period, 1990-1999............................................................................................................ 12 

 11. Number of mobile equipment fires for surface of underground coal mines by suppression method, equipment 

 involved, and time period, 1990-1999............................................................................................................ 13 

 12. Number of fire injuries per number of mobile equipment fires causing injuries and total fires at surface of 

 underground coal mines by year, ignition sources, equipment involved, and location, 1990-1999 ............... 14 

 13. Number of mobile equipment fires, injuries, and risk rates for coal preparation plants by state, equipment 

 involved, and employees' working hours, 1990-1999 .................................................................................... 14 

 14. Number of mobile equipment fires, injuries, and risk rates for coal preparation plants by time period, 

 equipment involved, activity, and employees' working hours, 1990-1999.................................................... 15 

 15. Number of mobile equipment fires for coal preparation plants by ignition source, equipment involved, and 

 time period, 1990-1999 ................................................................................................................................. 16 

 16. Number of mobile equipment fires for coal preparation plants by method of detection, equipment involved, 

 and time period, 1990-1999............................................................................................................................ 16 

 17. Number of mobile equipment fires for coal preparation plants by suppression method, equipment involved, 

 and time period, 1990-1999............................................................................................................................ 17 

 18. Number of fire injuries per number of mobile equipment fires causing injuries and total fires at coal 

 preparation plants by year, ignition sources, equipment involved, and location, 1990-1999......................... 19 

 19. Number of mobile equipment fires, injuries, and risk rates for underground coal mines by state, equipment 

 involved, coal production, and employees' working hours, 1990-1999.......................................................... 19 

 20. Number of mobile equipment fires, injuries, and risk rates for underground coal mines by time period, 

 equipment involved, activity, and employees' working hours, 1990-1999..................................................... 20 

 21. Number of mobile equipment fires for underground coal mines by ignition source, equipment involved, and 

 time period, 1990-1999 .................................................................................................................................. 20 

 22. Number of mobile equipment fires for underground coal mines by method of detection, equipment involved, 

 and time period, 1990-1999............................................................................................................................ 21 

 23. Number of mobile equipment fires for underground coal mines by suppression method, equipment involved, 

 and time period, 1990-1999............................................................................................................................ 21 

 24. Number of fire injuries per number of mobile equipment fires causing injuries and total fires in underground 

 coal mines by year, ignition source, equipment involved, and location, 1990-1999...................................... 22 

 25. Number of mobile equipment fires, injuries, and risk rates for surface metal/nonmetal mines by state, 

 equipment involved, and employees' working hours, 1990-1999.................................................................. 23 

 26. Number of mobile equipment fires, injuries, fatalities, and risk rates for surface metal/nonmetal mines by 

 time period, equipment involved, activity, and employees' working hours, 1990-1999................................ 23 

 27. Number of mobile equipment fires for surface metal/nonmetal mines by ignition source, equipment involved, 

 and time period, 1990-1999............................................................................................................................ 26 

 28. Number of mobile equipment fires for surface metal/nonmetal mines by method of detection, equipment 

 involved, and time period, 1990-1999............................................................................................................ 26 

 29. Number of mobile equipment fires for surface metal/nonmetal mines by suppression method, equipment 

 involved, and time period, 1990-1999............................................................................................................ 27 

 30. Number of fire injuries per number of mobile equipment fires causing injuries and total fires at surface 

 metal/nonmetal mines by year, ignition source, equipment involved, and location, 1990-1999.................... 27 
TABLES–Continued 

Page 

 31. Number of mobile equipment fires, injuries, and risk rates for surface sand and gravel and stone mines by 

 state, equipment involved, and employees' working hours, 1990-1999 ........................................................ 28 

 32. Number of mobile equipment fires, injuries, fatalities, and risk rates for surface sand and gravel and stone 

 mines by time period, equipment involved, activity, and employees' working hours, 1990-1999...................... 30 

 33. Number of mobile equipment fires for surface sand and gravel and stone mines by ignition source, 

 equipment involved, and time period, 1990-1999 .......................................................................................... 31 

 34. Number of mobile equipment fires for surface sand and gravel and stone mines by method of detection, 

 equipment involved, and time period, 1990-1999 .......................................................................................... 32 

 35. Number of mobile equipment fires for surface sand and gravel and stone mines by suppression method, 

 equipment involved, and time period, 1990-1999 .......................................................................................... 32 

 36. Number of fire injuries per number of mobile equipment fires causing injuries and total fires at surface sand 

 and gravel and stone mines by year, ignition source, equipment involved, and location, 1990-1999............ 34 

 37. Number of mobile equipment fires, injuries, and risk rates for metal/nonmetal and stone mills by state, 

 equipment involved, and employees' working hours, 1990-1999................................................................... 34 

 38. Number of mobile equipment fires, injuries, and risk rates for metal/nonmetal and stone mills by time period, 

 equipment involved, activity, and employees' working hours, 1990-1999..................................................... 35 

 39. Number of mobile equipment fires for metal/nonmetal and stone mills by ignition source, equipment 

 involved, and time period, 1990-1999............................................................................................................ 35 

 40. Number of mobile equipment fires for metal/nonmetal and stone mills by method of detection, equipment 

 involved, and time period, 1990-1999............................................................................................................ 38 

 41. Number of mobile equipment fires for metal/nonmetal and stone mills by suppression method, equipment 

 involved, and time period, 1990-1999............................................................................................................ 38 

 42. Number of fire injuries per number of mobile equipment fires causing injuries and total fires at 

 metal/nonmetal and stone mills by year, ignition source, equipment involved, and location, 1990-1999 ..... 38 

 43. Number of mobile equipment fires, injuries, and risk rates for underground metal/nonmetal and stone mines 

 by state, equipment involved, and employees' working hours, 1990-1999 .................................................... 39

 44. Number of mobile equipment fires, injuries, and risk rates for underground metal/nonmetal and stone mines 

 by time period, equipment involved, activity, and employees' working hours, 1990-1999............................ 39 

 45. Number of mobile equipment fires for underground metal/nonmetal and stone mines by ignition source, 

 equipment involved, and time period, 1990-1999 .......................................................................................... 40 

 46. Number of mobile equipment fires for underground metal/nonmetal and stone mines by method of detection, 

 equipment involved, and time period, 1990-1999 .......................................................................................... 41 

 47. Number of mobile equipment fires for underground metal/nonmetal and stone mines by suppression method, 

 equipment involved, and time period, 1990-1999 ......................................................................................... 41 

 48. Number of fire injuries per number of mobile equipment fires causing injuries and total fires in underground 

 metal/nonmetal and stone mines by year, ignition source, equipment involved, and location, 1990-1999.... 41 

 49. Major mobile equipment fire findings for all coal mining categories, 1990-1999.............................................. 44 

 50. Major mobile equipment fire injury findings for all coal mining categories, 1990-1999.................................... 45 

 51. Major mobile equipment fire findings for all metal/nonmetal mining categories, 1990-1999............................ 49 

 52. Major mobile equipment fire injury findings for all metal/nonmetal mining categories, 1990-1999 ................. 50 

UNIT OF MEASURE ABBREVIATIONS USED IN THIS REPORT 

 hr hour st short tons 

 

 min minute °F degrees Fahrenheit 

 
ANALYSES OF MOBILE EQUIPMENT FIRES FOR ALL U.S. SURFACE AND 

UNDERGROUND COAL AND METAL/NONMETAL MINING CATEGORIES, 

1990-1999 

By Maria I. De Rosa1 

ABSTRACT 

 This report analyzes mobile equipment fires for all U.S. surface and underground coal and 

metal/nonmetal mining categories by state and 2 year time periods during 1990-1999. Risk rate values are 

derived, and ignition source, methods of fire detection and suppression, and other variables are examined. 

The data were derived from MSHA mine fire accident publications and verbal communications with mine 

personnel. The analyses will provide the National Institute for Occupational Safety and Health (NIOSH), the 

Mine Safety and Health Administration (MSHA), and the mining industry with a better understanding of the 

hazards associated with mobile equipment fires and will create a basis for future fire research programs. 

1

Industrial hygienist, Pittsburgh Research Laboratory, National Institute for Occupational Safety and Health, Pittsburgh, PA.
2

INTRODUCTION

Mobile equipment fires are extremely hazardous to the safety

of miners and their livelihood, especially when they occur in the

confined space of underground mines. Enactment of safety laws

[30 CFR2

 75], which require machine fire suppression systems

on all underground coal mine diesel equipment and electrical

powered mine face equipment using non-fire-resistant hydraulic

fluids, has greatly improved the safety of miners. However,

equipment fires still occur with disastrous consequences. Fireresistant hydraulic fluid for use in equipment is not required at

all metal/nonmetal mining operations.

This report analyzes mobile equipment fires for all surface

and underground coal and metal/nonmetal3

 mining categories

during 1990-1999. Fires involving semimobile equipment such

as shearers, hoists, and continuous miners have also been

included. The mining categories include surface coal mines,

surface of underground coal mines, coal preparation plants, and

underground coal mines; surface metal/nonmetal mines, surface

sand and gravel and stone mines, metal/nonmetal and stone

mills, and underground metal/nonmetal and stone mines. No

equipment fires were reported for surface of underground

metal/nonmetal and stone mines.

For each category, the injury risk rates for a 10-year time

period and for five successive 2-year time periods within the

10-year period are derived. The fire risk rates were derived for

surface and underground coal only.4

 Also, risk rate values for

individual states for a 10-year time period are derived. Other

variables such as ignition source, methods of

detection/suppression, and other variables are explored.

Included are mobile equipment fire data for working contractors.

The data were derived from "Injury Experience in Mining"

[MSHA 1990b,c,d,e,f; 1991a,b,c,d,e; 1992a,b,c,d,e; 1993a,b,

c,d,e; 1994a,b,c,d,e; 1995a,b,c,d,e; 1996a,b,c,d,e; 1997a,b,c,d,e;

1998a,b,c,d,e; 1999b,c,d,e,f], "Fire Accident Reports" [MSHA

1990a,g; 1991f; 1992f,g,h; 1993f; 1994f,g,h,i; 1995f,g,h;

1996f,g; 1997f,g; 1998f; 1999a], MSHA "Fire Accident Abstracts" internal publications, and verbal communications with

mine personnel. Mining companies are required by 30 CFR 50

to report to MSHA all fires that result in injuries and those that

cannot be extinguished within 30min from their discovery. A

small number of courtesy reports (regarding fires without

injuries lasting <30 min) reported in the "Abstracts" were

included in the analyses.

The analyses, which are done by state (10-year time period)

and five 2-year time periods, include the number of equipment

fires, fire injuries, risk rates,4

 employees' working hours, and

production3

 according to the equipment involved. Also, by time

period, the analyses include other variables such as activity,

ignition source, and methods of detection and suppression according to the equipment involved. Furthermore, the analyses

include the number of fire injuries and fatalities per number of

equipment fires causing injuries and total fires by year, ignition

source, equipment involved, and location. For comparison

purposes, major fire and fire injury findings are reported for

1990-1999.

The current analyses will provide the National Institute for

Occupational Safety and Health, MSHA, and the mining

industry with a better understanding of the causes and hazards

associated with equipment fires and fire injuries and will create

a basis for present and future research programs.

Previous analyses/studies by the former U.S. Bureau of

Mines (USBM) included: mobile equipment accidents at surface coal mines during 1989-1991 [Aldinger et al. 1995]; underground coal mine fires during 1950-1977 [McDonald and

Pomroy 1980] and 1978-1992 [Pomroy and Carigiet 1995];

underground and surface metal/nonmetal mine fires during

1950-1984 [Butani and Pomroy 1987]; and equipment fire

detection and suppression systems [Johnson and Forshey 1975;

Pomroy and Bickel 1980].

METHODOLOGIES

In this report, the methodologies used to analyze the data

deal with actual numbers and calculated values.

1. For each mining category, actual numbers include the

total numbers of equipment fires, injuries, employees' working

hours, and production for a 10-year time period (1990-1999) and

for five successive 2-year time periods within the 10-year period

according to the equipment involved and activity. Actual

numbers of fires, injuries, employees' working hours, and

production4

 were also reported by state for the 10-year time

2

Code of Federal Regulations. See CFR in references.

3

"Metal/nonmetal" includes stone and sand and gravel. 3

Coal production values used to calculate the fire risk rates have been

reported for these two mining categories only.

period. Also, for the five 2-year time periods, the actual number

of fires were reported by ignition source and methods of

detection and suppression according to the equipment involved.

Furthermore, actual numbers of fire injuries per number of

equipment fires causing injuries and total fires were reported by

year, ignition source, equipment involved, and location for

1990-1999.

2. For each mining category, the calculated values include

the fire and injury risk rates during the 10-year time period and

the five 2-year time periods. The fire risk rate (Frr) values were

calcuated according to the USBM formula [Pomroy and Carigiet

1995]. The injury risk rate (Irr) values were calculated
3

according to the MSHA formula (incidence rate (IR) = number

of injuries multiplied by 200,000 working hours divided by the

number of working hours) [MSHA 1990b,c,d,e,f; 1991a,b,c,d,e;

1992a,b,c,d,e; 1993a,b,c,d,e; 1994a,b,c,d,e; 1995a,b,c,d,e;

1996a,b,c,d,e; 1997a,b,c,d,e; 1998a,b,c,d,e; 1999b,c,d,e,f].

Also, fire and injury risk rate values for individual states during

the 10-year time period were calculated according to the

abovementioned formulas.

Of note is that only the risk rate values for the 10-year and

five 2-year time periods and risk rate values for individual states

with the highest number of fires and fire injuries have been

considered for comparison purposes. The fatality risk rate

values were not calculated because of the extremely small

number of fatalities occurring during the 10-year period.

Calculations of risk rate values and other values were done

as follows:

a. Fire risk rate values (Frr): Number of fires per million

tons of coal produced [Pomroy and Carigiet 1995] (calculated for surface and underground coal mines only).

b. Injury risk rate values (Irr): Number of injuries multiplied by 200,000 working hours per total employees'

working hours [MSHA 1990b,c,d,e,f; 1991a,b,c,d,e;

1992a,b,c,d,e; 1993a,b,c,d,e; 1994a,b,c,d,e;1995a,b,c,d,e;

1996a,b,c,d,e; 1997a,b,c,d,e; 1998a,b,c,d,e;

1999b,c,d,e,f]. The Irr value is the average risk rate value

for the number of injuries per 200,000 working hours for

a given time period.

c. Total employees' working hours (Ewhr) value during

1990-1999: Sum of 10 yearly Ewhr values for all the

states involved in equipment fires. This value also

includes the Ewhr value reported for all of the other states

not involved in equipment fires. The Ewhr value for each

state (10-year time period) is the sum of 10 yearly Ewhr

values for that state.

d. Total employees' working hours for five 2-year time

periods: Sum of two yearly Ewhr values for all of the

states, with and without equipment fires, within that

2-year time period.

e. The coal production (CP) values in short tons were

calculated similarly.

f. Calculations of Ewhr values for the states within mining

categories with more than one subcategory (e.g.,

metal/nonmetal and stone mills) were made according to

that subcategory.

g. All flame cutting/welding fires and injuries occurring on

mobile equipment, which include fires involving welders'

clothing, oxyfuels, and/or grease embedded in the

equipment's mechanical components, have been reported

here.

MOBILE EQUIPMENT DATA ANALYSIS FOR ALL COAL MINING CATEGORIES

MOBILE EQUIPMENT FIRES AT SURFACE

COAL MINES

At surface coal mines, there were a total of 140 equipment

fires during 1990-1999; 56 of those fires caused 56 injuries

(table 1 and figure 1). Eleven fires with six injuries involved

contractors. In all, five pieces of equipment (3.6%) involved in

the fires had machine fire suppression systems.

The highest number of equipment fires occurred in Kentucky

(39 fires and 18 injuries), followed by West Virginia (19 fires

and 9 injuries), Pennsylvania (16 fires and 6 injuries), and

Indiana (15 fires and 5 injuries). Pennsylvania had the highest

fire risk rate (Frr = 0.07); Kentucky had the highest injury risk

rate (Irr = 0.027). For surface coal mines, the total Ewhr value

was 729 × 106

 hr (Irr = 0.015); the total CP value was 6,355

× 106

 st (Frr = 0.022).

The equipment involved, mostly during working activities,

included haulage/utility trucks (46 fires and 24 injuries), dozers

(25 fires and 8 injuries), shovels (22 fires and 10 injuries),

loaders (22 fires and 5 injuries), and drills (12 fires and 4 injuries) (table 2 and figure 2).

A large number of equipment fires (77 fires or 55%) were

caused by pressurized hydraulic fluid/fuel sprayed onto

equipment hot surfaces due to ruptured lines and failed fittings

and gaskets (table 3 and figure 2). Of note is that the wear and

tear of lines, fittings, and gaskets may occur more readily

beyond 5,000 operating hours, which was acknowledged by

mine personnel during field visits.

Most of the hydraulic fluid/fuel fires, although detected by

the operators when they started as flames/flash fires, a popping

sound, or power loss, often raged out of control (requiring at

least 15 fire-fighting interventions) because of the continuous

flow of fluids from pumps and tanks due to engine shutoff

failure, lack of an emergency line drainage system (whose flow

is not affected by the engine shutoff system), difficulty in

reaching available emergency systems at ground level due to

flames engulfing the area, or lack of effective and rapid local

fire-fighting response capabilities. On at least five occasions the

cab was suddenly engulfed in flames, forcing the operator to

exit the cab under difficult conditions, most likely due to the

ignition of flammable vapors and mists that formed and

penetrated the cab during the spraying of hydraulic fluid/fuel

onto equipment hot surfaces. Dual activation (three activations)

of machine fire suppression/engine shutoff systems succeeded

in abating the flames temporarily. However, the flames

reignited, fueled by the flow of pressurized hydraulic fluid/fuel

entrapped in the lines. Four fires were detected late (which

made fire-fighting efforts ineffective), and 10 were undetected

and burned themselves out (table 4 and figure 2).
4

Figure 2.—Major variables for mobile equipment fires at surface coal mines, 1990-1999. (FE = portable fire extinguisher; FSS = machine

fire suppression system.)

Figure 1.—Mobile equipment fires and injuries for surface coal mines by state, 1990-1999.
5

Table 1.—Number of mobile equipment fires, injuries, and risk rates for surface coal mines by state,

equipment involved, coal production, and employees’ working hours, 1990-1999

State1 Equipment1 No. fires1 No. Injuries Ewhr,2

 106 hr Cp,2106 st Irr3 Frr3

AL . . . . . Truck . . . . . . . . . . . . 1 1

Drill . . . . . . . . . . . . . 1 1

Loader .......... 1 1

Shovel . . . . . . . . . . 1 — 25.5 80.3 0.024 0.05

AZ . . . . . Truck . . . . . . . . . . . . 1 —

Shovel . . . . . . . . . . 1 1 16.3 120 0.012 0.017

CO . . . . Truck . . . . . . . . . . . . 1 —

Dozer . . . . . . . . . . . 1 — 11.8 90 — 0.022

IL . . . . . . Truck . . . . . . . . . . . . 1 —

Shovel . . . . . . . . . . 1 — 24.2 93.6 — 0.021

IN . . . . . Loader .......... 1 —

Drill . . . . . . . . . . . . . 1 —

Truck . . . . . . . . . . . . 5 2

Dozer . . . . . . . . . . . 1 —

Shovel . . . . . . . . . . 5 2

Excavator . . . . . . . . 2 1 53.5 290.3 0.02 0.052

KS . . . . . Dozer . . . . . . . . . . . 1 — 1.5 3.7 — 0.27

KY . . . . . Loader .......... 5 1

Truck . . . . . . . . . . . . 15 7

Dozer . . . . . . . . . . . 4 2

Backhoe . . . . . . . . . 3 2

Drill . . . . . . . . . . . . . 5 3

Shovel/bucket . . . . . 5 2

Auger/miner ...... 2 1 133.2 602 0.027 0.06

LA . . . . . Dozer . . . . . . . . . . . 1 — 2.5 27.2 — 0.037

MO . . . . Truck . . . . . . . . . . . . 1 1

Dozer . . . . . . . . . . . 1 1

Drill . . . . . . . . . . . . . 1 — 4.8 11.8 0.08 0.25

Loader .......... 1 —

Shovel . . . . . . . . . . 1 — 16.2 394 — 0.005

NM . . . . Truck . . . . . . . . . . . . 1 1

Loader .......... 1 —

Dozer . . . . . . . . . . . 2 — 30 245.6 0.007 0.016

OH . . . . Loader .......... 2 1

Truck . . . . . . . . . . . . 1 —

Dozer . . . . . . . . . . . 3 1 40 167.3 0.01 0.04

OK . . . . Scraper . . . . . . . . . . 1 1 6 16 0.03 0.063

PA . . . . . Loader .......... 4 1

Truck . . . . . . . . . . . . 3 2

Dozer . . . . . . . . . . . 2 —

Drill . . . . . . . . . . . . . 2 —

Shovel . . . . . . . . . . 5 3 72.6 228.1 0.017 0.07

TX . . . . . Truck . . . . . . . . . . . . 3 2

Shovel . . . . . . . . . . 2 1

Drill . . . . . . . . . . . . . 1 —

Miner . . . . . . . . . . . . 1 —

Dozer . . . . . . . . . . . 1 1 60.1 535.2 0.013 0.015

VA . . . . . Loader .......... 3 —

Dozer . . . . . . . . . . . 3 3 22.5 88.5 0.027 0.07

WV . . . . Loader .......... 2 1

Truck . . . . . . . . . . . . 11 7

Dozer . . . . . . . . . . . 4 —

Drill . . . . . . . . . . . . . 1 —

Shovel . . . . . . . . . . 1 1 94.5 455.8 0.02 0.042

WY . . . . Loader .......... 3 —

Truck . . . . . . . . . . . . 2 1

Dozer . . . . . . . . . . . 1 —

Excavator . . . . . . . . 1 —

Auger/miner . . . . . . 2 — 76 2,454.4 0.003 0.004

All other states . . . . . . . . . . . . . . — — 38 551.2 — —

Total . . . . . . . . . . . . . . . . . . . 140 56 729 6,355 3

0.015 30.022 1

Derived from MSHA "Fire Accident Abstract" and "Fire Accident Report" publications. 2

Derived from MSHA "Injury Experience in Coal Mining" publications. 3

Calculated according to MSHA and USBM formulas reported in the "Methodologies" section.
6

Table 2.–Number of mobile equipment fires, injuries, and risk rates for surface coal mines by time period, equipment involved, activity,

and employees’ working hours, 1990-1999

Equipment Activity

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

Loader .......... Loading . . . . . . . . . . . . 8 2 1 1 5 – 5 1 2 – 21 4

Flame cutting/welding – – 1 1 – – – – – – 1 1

Dozer . . . . . . . . . . . Mining . . . . . . . . . . . . . 6 1 3 – 3 3 1 – 4 1 17 5

Flame cutting/welding 1 1 – – 1 1 – – 2 1 4 3

Maintenance/idle .... 1 – 1 – – – 2 – – – 4 –

Shovel/bucket . . . . . Mining . . . . . . . . . . . . . 3 1 5 2 – – – – 1 – 9 3

Flame cutting/welding 4 2 2 1 1 – 1 1 2 1 10 5

Maintenance/idle .... 1 – – – – – 2 2 – – 3 2

Scraper . . . . . . . . . . Flame cutting/welding – – 1 1 – – – – – – 1 1

Drill . . . . . . . . . . . . . Drilling ............ 3 1 2 1 1 – – – – – 6 2

Flame cutting/welding 1 1 2 1 1 – – – – – 4 2

Maintenance/idle .... 1 – 1 – – – – – – – 2 –

Haulage/utility truck Haulage/utility . . . . . . . 9 4 4 2 7 3 8 3 2 1 30 13

Flame cutting/welding 1 1 2 2 4 4 1 1 1 1 9 9

Maintenance/idle .... 2 1 3 1 1 – 1 – – – 7 2

Excavator . . . . . . . . Mining . . . . . . . . . . . . . – – 1 – – – – – 1 – 2 –

Flame cutting/welding – – – – 1 – 1 1 – – 2 1

Auger/miner . . . . . . Mining . . . . . . . . . . . . . – – 1 – 1 – 1 – – – 3 –

Flame cutting/welding – – – – 2 1 – – – – 2 1

Backhoe . . . . . . . . . Flame cutting/welding 2 2 1 – – – – – – – 3 2

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 17 31 13 28 12 23 9 15 5 140 56

Ewhr,1

 106 hr . . . . . . . . . . . . . . . . . . . . . . 177 154 143 131 124 729

Irr2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.019 0.017 0.017 0.014 0.008 2

0.015

CP1

, 106 st . . . . . . . . . . . . . . . . . . . . . . . . 1,182 1,176 1,267 1,325 1,405 6,355

Frr2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.036 0.026 0.022 0.017 0.011 2

0.022 1

Derived from MSHA "Injury Experience in Mining" publications. 2

Calculated according to MSHA and USBM formulas reported in the "Methodologies" section.

Table 3.–Number of mobile equipment fires for surface coal mines by ignition source,

equipment involved, and time period, 1990-1999

Equipment Ignition source

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Loader . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces . 8 1 5 5 2 21

Flame cutting/welding spark/slag . . . . . . . . . . . – 1 – – – 1

Dozer . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces . 5 2 3 1 2 13

Electrical short/arcing . . . . . . . . . . . . . . . . . . . . – 2 – 2 1 5

Engine/mechanical malfunctions ........... 1 – – – – 1

Flame cutting/welding spark/slag . . . . . . . . . . . 1 – 1 – 2 4

Natural gas explosion . . . . . . . . . . . . . . . . . . . . 1 – – – 1 2

Shovel/bucket . . . . . Flammable liquid on hot surfaces . . . . . . . . . . . 1 – – 2 – 3

Flame cutting/welding spark/slag . . . . . . . . . . . 4 2 1 1 2 10

Engine/mechanical friction ................ 1 1 – – – 2

Hydraulic fluid/fuel on equipment hot surfaces . 2 3 – – 1 6

Electrical short/arcing . . . . . . . . . . . . . . . . . . . . – 1 – – – 1

Scraper . . . . . . . . . . Flame cutting/welding spark/slag . . . . . . . . . . . – 1 – – – 1

Drill . . . . . . . . . . . . . Flame cutting/welding spark/slag . . . . . . . . . . . 1 2 1 – – 4

Hydraulic fluid/fuel on equipment hot surfaces . 2 3 1 – – 6

Flammable liquid on hot surfaces . . . . . . . . . . . 1 – – – – 1

Mechanical friction/explosion .............. 1 – – – – 1

Haulage/utility truck Hydraulic fluid/fuel on equipment hot surfaces . 8 4 8 6 1 27

Mechanical malfunction .................. 1 3 – 2 1 7

Flame cutting/welding spark/slag . . . . . . . . . . . 1 2 4 1 1 9

Electrical short/arcing . . . . . . . . . . . . . . . . . . . . 2 – – 1 – 3

Excavator . . . . . . . . Flame cutting/welding spark/slag . . . . . . . . . . . – – 1 1 – 2

Hydraulic fluid on equipment hot surfaces .... – 1 – – 1 2

Auger/miner . . . . . . Hydraulic fluid on equipment hot surfaces .... – 1 1 – – 2

Flame cutting/welding spark/slag . . . . . . . . . . . – – 2 – – 2

Electrical short/arcing . . . . . . . . . . . . . . . . . . . . – – – 1 – 1

Backhoe . . . . . . . . . Flame cutting/welding spark/spark . . . . . . . . . . 2 1 – – – 3

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 31 28 23 15 140
7

Table 4.–Number of mobile equipment fires for surface coal mines by method of detection,

equipment involved, and time period, 1990-1999

Equipment Method of detection

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Loader . . . . . . . . . . . . . Visual-flames/flash fire . . 7 1 3 3 2 16

Popping sound ........ – – 2 1 – 3

Visual–smoke . . . . . . . . . 1 – – 1 – 2

Visual-sparks . . . . . . . . . – 1 – – – 1

Dozer . . . . . . . . . . . . . . Undetected ........... 1 – – 1 1 3

Visual-smoke . . . . . . . . . 1 2 – 1 1 5

Late detection–smoke . . – – – 1 – 1

Visual-sparks . . . . . . . . . 1 – 1 – 1 3

Explosion . . . . . . . . . . . . 1 – – – 1 2

Visual-flames/flash fire . . 4 1 2 – 1 8

Power loss . . . . . . . . . . . – – – – 1 1

Smell . . . . . . . . . . . . . . . – 1 – – – 1

Popping sound ........ – – 1 – – 1

Shovel/bucket . . . . . . . . Visual-flames/flash fire . . 3 2 – 2 1 8

Visual-sparks . . . . . . . . . 3 – 1 1 2 7

Popping sound ........ 1 – – – – 1

Undetected ........... 1 1 – – – 2

Visual-smoke . . . . . . . . . – 3 – – – 3

Power loss . . . . . . . . . . . – 1 – – – 1

Scraper . . . . . . . . . . . . . Visual-sparks . . . . . . . . . – 1 – – – 1

Drill . . . . . . . . . . . . . . . . Visual-sparks . . . . . . . . . 1 1 1 – – 3

Undetected ........... 1 1 – – – 2

Explosion . . . . . . . . . . . . 1 – – – – 1

Popping sound ........ 1 – – – – 1

Visual-flames/flash fire . . 1 3 1 – – 5

Haulage/utility truck . . . Visual-flames/flash fire . . 9 3 7 8 2 29

Visual-sparks . . . . . . . . . 1 2 3 1 1 8

Late detection-smoke . . . – 1 – 1 – 2

Visual-smoke . . . . . . . . . 2 – – – – 2

Popping sound ........ – 1 – – – 1

Power loss . . . . . . . . . . . – 2 – – – 2

Undetected ........... – – 1 – – 1

Explosion . . . . . . . . . . . . – – 1 – – 1

Excavator . . . . . . . . . . . Visual-sparks . . . . . . . . . – – – 1 – 1

Visual-flames/flash fire . . – 1 – – 1 2

Undetected ........... – – 1 – – 1

Auger/miner . . . . . . . . . Late detection-smoke . . . – – 1 – – 1

Visual-flames/flash fire . . – 1 1 – – 2

Visual-sparks . . . . . . . . . – – 1 1 – 2

Backhoe . . . . . . . . . . . . Visual-sparks . . . . . . . . . 2 1 – – – 3

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 31 28 23 15 140

Fire brigades and fire departments, handicapped by travel

distances, fought the hydraulic/fuel fires with foam (mostly used

by fire brigades), dry chemical powder (mostly used by fire

departments), and water. Ten pieces of equipment were destroyed or heavily damaged because of failed fire suppression

and fire-fighting methods, late fire detection, undetected fires,

or fire size (table 5 and figure 2).

Other ignition sources included flame cutting/welding

spark/slag (this source usually caused fires involving welders'

clothing, oxyfuel, or grease embedded in the equipment's

mechanical components), electrical short/arcing of wires and

cables, engine/mechanical malfunctions/friction/explosion, and

flammable liquids on hot surfaces (table 3 and figure 2). The

flame cutting/welding fires, detected mostly as sparks, were

suppressed by manual methods (welders' method to extinguish

clothing fires) or with portable fire extinguishers (welders'

method to extinguish oxyfuel and/or grease fires). The

electrical, engine malfunction/friction/explosion, and flammable

liquid fires, detected as smoke or flames, were also extinguished

with portable fire extinguishers (table 5 and figure 2).

The five hydraulic fluid/fuel fires involving equipment with

fire suppression systems behaved as follows. In three instances,

the flames, which abated temporarily upon dual activation of the

fire suppression/engine shutoff systems, reignited, fueled by the

fluids entrapped in the lines. In the other two instances, the fires

raged out of control because of engine shutoff failure upon

activation of the machine fire suppression system.

Data during the five time periods, including the number of

fires, injuries, risk rates, employees' working hours, and coal

production according to the equipment involved and activity are

shown in table 2 and partly illustrated in figure 3. Other

variables such as ignition source and methods of detection and

suppression are shown in tables 3-5.

Equipment fires and injuries decreased sharply throughout

the five time periods (the decline in haulage truck fires was

evident only during the last period (table 3)), accompanied by a
8

Figure 3.—Mobile equipment fires, injuries, risk rates, employees' working hours, and coal production (coal production for surface and

underground coal mines only) by time period for each coal mining category, 1900-1999.

Table 5.–Number of mobile equipment fires for surface coal mines by suppression method, equipment involved and time period, 1990-1999

Equipment Suppression method

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Loader . . . . . . . . . . . . . . . . FE-water-foam-dry chemical powder1 . . 5 – 5 4 2 16

FE/manual2 ....................... 1 1 – – – 2

FE-FSS-water-dry chemical powder3 ... 1 – – 1 – 2

Water–

dry chemical powder4 .......... 1 1 – – – 2

Dozer . . . . . . . . . . . . . . . . . FE-dry chemical powder4 . . . . . . . . . . . . 5 2 3 1 1 12

Portable fire extinguisher ............ 1 2 – 2 1 6

FE/manual2 ....................... 1 – 1 – 2 4

FE-FSS-dry chemical powder3 ........ – – – – 1 1

Destroyed/heavily damaged5 ......... 1 – – – 1 2

Shovel/bucket . . . . . . . . . . . FE-water-foam-dry chemical powder1 .. 2 3 – – 1 6

FE/manual2 . . . . . . . . . . . . . . . . . . . . . . . 4 3 1 3 2 13

Destroyed/heavily damaged5 ......... 1 – – – – 1

Water-dry chemical powder4 .......... 1 1 – – – 2

Scraper . . . . . . . . . . . . . . . . FE/manual2 ....................... – 1 – – – 1

Drill . . . . . . . . . . . . . . . . . . . FE-water-foam-dry chemical powder1 .. 2 2 1 – – 5

FE/manual2 ....................... 1 1 1 – – 3

Water-dry chemical powder4 .......... – 1 – – – 1

Destroyed/heavily damaged5 ......... 2 1 – – – 3

Haulage/utility truck . . . . . . FE-water-foam-dry chemical powder1 . . 7 3 4 5 1 20

FE/manual2 . . . . . . . . . . . . . . . . . . . . . . . 4 4 4 3 1 16

Water-dry chemical powder4 .......... 1 2 2 1 – 6

FE-FSS-dry chemical powder3 ........ – – – 1 1 2

Destroyed/heavily damaged5 ......... – – 2 – – 2

Excavator . . . . . . . . . . . . . . FE-water-foam-dry chemical powder1 .. – 1 – – 1 2

FE/manual2 ....................... – – – 1 – 1

Destroyed/heavily damaged5 ......... – – 1 – – 1

Auger/miner . . . . . . . . . . . . FE-water-foam-dry chemical powder1 .. – – 2 – – 2

FE/manual2 ....................... – – 1 – – 1

Water-dry chemical powder4 .......... – 1 – – – 1

Destroyed/heavily damaged5 ......... – – – 1 – 1

Backhoe . . . . . . . . . . . . . . . FE-water-foam-dry chemical powder1 .. – 1 – – – 1

FE/manual2 ....................... 2 – – – – 2

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 31 28 23 15 140

FE Portable fire extinguisher.

FSS Machine fire suppression system.

1

Methods used by fire brigades (mostly foam) and fire departments (mostly dry chemical powder). 2

Methods used by welders to extinguish clothing or oxyfuel/grease fires (grease embedded in the equipment’s mechanical components). 3

Methods used by fire departments following available FSS discharge by operator. 4

Method used by fire departments.

5

Usually due to failed fire suppression and fire-fighting methods, late fire detection, undetected fires, or fire size.
9

decline in employees' working hours and a small increase in coal

production.

During 1990-1991, there were 43 fires (Frr = 0.036) and 17

fire injuries (Irr = 0.019). The equipment involved included

haulage/utility trucks (12 fires and 6 injuries), shovels (8 fires and

3 injuries), loaders (8 fires and 2 injuries), dozers (8 fires and 2

injuries), and drills (5 fires and 2 injuries) mostly during haulage,

loading, mining, and drilling activities. The Ewhr value was 177

× 106

 hr; the CP value was 1,182 × 106 st. The most common

ignition sources were hydraulic fluid/fuel sprayed onto equipment

hot surfaces and flame cutting/welding spark/ slag, followed by

engine/mechanical malfunctions/ friction explosion and electrical

short/arcing. The most frequent methods of detection were

operators who saw flames/flash fires, followed by operators/

miners/welders who saw smoke or sparks. The most commonly

used fire suppression methods were foam, dry chemical powder,

and water, followed by manual methods and portable fire

extinguishers (four equipment fires were not extinguished).

A machine fire suppression system was discharged once.

During 1992-1993, there were 31 fires (Frr = 0.026) and 13

fire injuries (Irr = 0.017). The equipment involved included

haulage/utility trucks (nine fires and five injuries), drills (five

fires and two injuries), shovels (seven fires and three injuries),

and dozers (four fires and no injuries) mostly during

haulage/utility, drilling, and mining activities. The Ewhr was

154 × 106

 hr; the CP value was 1,176 × 106 st. The most

common ignition sources were hydraulic fluid/fuel sprayed onto

equipment hot surfaces, followed by flame cutting/welding

spark/slag and electrical short/arcing. The most frequent

methods of detection were operators who saw flames/flash fires

and welders/operators/miners who saw sparks or smoke (one

fire was detected late). The most commonly used suppression

methods were foam, dry chemical powder, water, and portable

fire extinguishers (one equipment fire was not extinguished).

During 1994-1995, there were 28 fires (Frr = 0.022) and 12

fire injuries (Irr = 0.017). The equipment involved included

haulage/utility trucks (12 fires and 7 injuries), loaders (5 fires

and no injuries), dozers (4 fires and 4 injuries), and augers (3

fires and 1 injury) mostly during haulage, loading, and mining

activities. The Ewhr value was 143 × 106

 hr; the CP value was

1,267 × 106

 st. The most common ignition sources were hydraulic fluid/fuel sprayed onto equipment hot surfaces, followed

by flame cutting/welding spark/slag. The most frequent methods of detection were operators who saw flames/flash fires and

welders who saw sparks (two fires were undetected). The most

commonly used suppression methods were foam, dry chemical

powder, water, and portable fire extinguishers (three equipment

fires were not extinguished).

During 1996-1997, there were 23 fires (Frr = 0.017) and 9

fire injuries (Irr = 0.014). The equipment involved included

haulage/utility trucks (10 fires and 4 injuries), dozers (3 fires

and no injuries), loaders (5 fires and 1 injury), and shovels (3

fires and 3 injuries) mostly during haulage, loading, and mining

activities. The Ewhr value was 131 × 106

 hr; the CP value was

1,325 × 106

 st. The most common ignition sources were

hydraulic fluid/fuel sprayed onto equipment hot surfaces,

followed by electrical short/arcing and flame cutting/welding

spark/slag. The most frequent methods of detection were operators who saw flames/flash fires and miners/welders who saw

smoke, flames, or sparks. The most commonly used

suppression methods were foam, dry chemical powder, and

water, followed by manual methods and portable fire

extinguishers (one equipment fire was not extinguished). The

machine fire suppression systems were discharged twice.

During 1998-1999, there were 15 equipment fires (Frr

= 0.011) and 5 fire injuries (Irr = 0.008). The equipment

involved included dozers (six fires and two injuries),

haulage/utility trucks (three fires and two injuries), shovels

(three fires and one injury), and loaders (two fires and no

injuries) mostly during mining, haulage, and loading activities.

The Ewhr value was 124 × 106

 hr; the CP value was 1,405 × 106

st. The most common ignition sources were hydraulic fluid/fuel

sprayed onto equipment hot surfaces, followed by flame

cutting/welding spark/slag and electrical short/arcing. The most

frequent methods of detection were operators who saw

flames/flash fires, welders who saw sparks, and

operators/miners who saw smoke. The most commonly used

suppression methods were foam, dry chemical powder, water,

and portable fire extinguishers (one equipment fire was not

extinguished). The machine fire suppression systems were

discharged twice.

Table 6 shows the number of fire injuries per number of fires

causing injuries and total fires by year, ignition source, equipment involved, and location. The highest number of fire injuries

was recorded in 1990 (10 fire injuries caused by 10 equipment

fires). These involved haulage/utility trucks, drills, shovels,

backhoes, and dozers during hydraulic fluid/fuel, flammable

liquids, mechanical friction/explosion, and flame

cutting/welding fires.

MOBILE EQUIPMENT FIRES AT SURFACE OF

UNDERGROUND COAL MINES

At surface of underground coal mines, there were 14 equipment fires with 4 injuries (caused by 4 equipment fires) during

1990-1999 (table 7 and figure 4). No contractor fires were reported for this mining category. In all, two pieces of equipment

(14%) involved in the fires had machine fire suppression

systems.

The highest number of equipment fires occurred in Pennsylvania (four fires and two injuries), followed by West Virginia

and Alabama (three fires and no injuries for each state) and

Kentucky (two fires and one injury). Pennsylvania had the

highest injury risk rate (Irr = 0.038). For surface of underground coal mines, the total Ewhr value was 97 × 106

 hr (Irr

= 0.008) (table 7).

The equipment involved, mostly during working activities,

included loaders (three fires and one injury), scrapers (three fires

and no injuries), and dozers and hoists (two fires and no injuries

for each) (table 8 and figure 5).

Most of the fires were caused by pressurized hydraulic

fluid/fuel (10 fires or 71%) sprayed onto equipment hot

surfaces. At least twice the cab was suddenly engulfed in

flames, forcing the operator to exit under difficult conditions
10

Table 6.–Number of fire injuries per number of mobile equipment fires causing injuries and total fires at surface coal mines by year,

ignition source, equipment involved, and location, 1990-1999

Year

No.

total

fires

No. fires

causing

injuries

No. fire

injuries Ignition source Equipment Location

1990 . . . 25 3 3 Hydraulic fluid/fuel on equipment hot surfaces Truck . . . . . . . . . . . Haulage area.

1 1 Mechanical friction/explosion . . . . . . . . . . . . . Drill . . . . . . . . . . . . Drilling area.

– 2 2 Flammable liquid on hot surfaces . . . . . . . . . . Shovel-truck . . . . . Maintenance area.

– 4 4 Flame cutting/welding spark/slag . . . . . . . . . . Truck-bucket/

 dozer-backhoe.

Flame cutting/welding areas.1

1991 . . . 18 5 5 Hydraulic fluid/fuel on equipment hot surfaces Loader-truck-dozer Loading/haulage/mining areas.

– 2 2 Flame cutting/welding spark/slag . . . . . . . . . . Back hoe-shovel-

 drill.

Flame cutting/welding areas.1

1992 . . . 16 3 3 Hydraulic fluid/fuel on equipment hot surfaces Drill-shovel . . . . . . Drilling/mining areas.

– 3 3 Flame cutting/welding spark/slag . . . . . . . . . . Loader-shovel . . . . Flame cutting/welding areas.1

– 1 1 Flammable liquid on hot surfaces . . . . . . . . . . Truck . . . . . . . . . . . Maintenance area.

1993 . . . 15 2 2 Hydraulic fluid/fuel on equipment hot surfaces Truck-loader . . . . . Haulage/loading areas.

– 3 3 Flame cutting/welding spark/slag . . . . . . . . . . Shovel-drill-truck . . Flame cutting/welding areas.1

1 1 Engine malfunction . . . . . . . . . . . . . . . . . . . . . Truck . . . . . . . . . . . Haulage area.

1994 . . . 15 2 2 Hydraulic fluid/fuel on equipment hot surfaces Dozer . . . . . . . . . . Mining area.

– 2 2 Flame cutting/welding spark/slag . . . . . . . . . . Dozer-truck . . . . . . Flame cutting/welding areas.1

1995 . . . 13 4 4 Hydraulic fluid/fuel on equipment hot surfaces Truck-dozer . . . . . Haulage/mining areas.

– 4 4 Flame cutting/welding spark/slag . . . . . . . . . . Auger-truck . . . . . . Flame cutting/welding/haulage

 areas.1

1996 . . . 12 3 3 Hydraulic fluid/fuel on equipment hot surfaces Truck-loader . . . . . Haulage/loading areas.

– 1 1 Flame cutting/welding spark/slag . . . . . . . . . . Truck . . . . . . . . . . . Flame cutting/welding areas.1

– 1 1 Engine malfunction . . . . . . . . . . . . . . . . . . . . . Truck . . . . . . . . . . . Haulage area.

1997 . . . 11 2 2 Flame cutting/welding spark/slag . . . . . . . . . . Shovel-excavator Flame cutting/welding areas.1

– 2 2 Flammable liquid on hot surfaces . . . . . . . . . . Shovel . . . . . . . . . Maintenance area.

1998 . . . 8 1 1 Hydraulic fluid/fuel on equipment hot surfaces Truck . . . . . . . . . . . Haulage area.

– 2 2 Flame cutting/welding spark/slag . . . . . . . . . . Dozer-truck . . . . . . Flame cutting/welding areas.1

– 1 1 Natural gas explosion . . . . . . . . . . . . . . . . . . . Dozer . . . . . . . . . . Pipeline area.

1999 . . . 7 1 1 Flame cutting/welding spark/slag . . . . . . . . . . Shovel . . . . . . . . . Flame cutting/welding areas.1

Total . . . 140 56 56

1

Includes working, mining, and maintenance areas.

Table 7.–Number of mobile equipment fires, injuries, and risk rates for surface of underground coal mines by state, equipment involved, and employees’ working hours, 1990-1999

State1 Equipment1 No. fires1 No. injuries1 Ewhr,2

 106 hr Irr3

AL . . . . . . . . . Dozer . . . . . . . . . . . . 1 –

Scraper . . . . . . . . . . . 2 – 5.8 –

CO . . . . . . . . Excavator . . . . . . . . . 1 – 3.6 –

KY . . . . . . . . . Loader . . . . . . . . . . . 2 1 23.1 0.01

PA . . . . . . . . . Hoist . . . . . . . . . . . . . 2 –

Highlift . . . . . . . . . . . 1 1

Tractor . . . . . . . . . . . 1 1 10.5 0.038

UT . . . . . . . . . Truck . . . . . . . . . . . . . 1 1 3.7 0.05

WV . . . . . . . . Loader ........... 1 –

Scraper ........... 1 –

Dozer . . . . . . . . . . . . 1 – 19.5 –

All other states . . . . . . . . . . . . . . . . . – – 30.35 –

Total . . . . . . . . . . . . . . . . . . . . . . 14 4 97 3

0.008 1

Derived from MSHA "Fire Accident Abstract" and "Fire Accident Report" publications. 2

Derived from MSHA "Injury Experience in Mining" publications. 3

Calculated according to MSHA formula reported in the "Methodologies" section.

most likely due to the ignition of flammable vapors and mists

that formed and penetrated the cab. Other ignition sources were

flame cutting/welding spark/slag (this source caused at least one

hydraulic fluid fire), electrical short/arcing, and overheated oil

on hot surfaces due to compressor malfunction (table 9 and

figure 5). Operators/ miners/ welders detected most of the fires

when they started as flames/flash fires, smoke, sparks, or as a

battery explosion. Two fires were detected late (which made

fire-fighting efforts ineffective) (table 10 and figure 5). Most of

the hydraulic fluid/ fuel fires grew out of control (requiring at

least once fire-fighting intervention) because of the continuous

flow of fluids from pumps and tanks due to engine shutoff

failure, lack of an emergency line drainage system, difficulty in

reaching available emergency systems at ground level, or lack

of effective and rapid local fire-fighting response capabilities.
11

Figure 4.—Mobile equipment fires and injuries for surface of underground coal mines by state, 1990-1999.

Table 8.–Number of mobile equipment fires, injuries, and risk rates for surface of underground coal mines by time period,

equipment involved, activity, and employees’ working hours, 1990-1999

Equipment Activity

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires 

No.

injuries

No.

fires

No.

injuries

No.

fires 

No.

injuries

Highlift . . . . . . . . Mining . . . . . . . . . . . . 1 1 – – – – – – – – 1 1

Hoist . . . . . . . . . . Hoisting . . . . . . . . . . 2 – – – – – – – – – 2 –

Loader ........ Loading ........... 2 1 – – – – – – 1 – 3 1

Haulage truck . . . Flame cutting/welding – – – – – – 1 1 – – 1 1

Scraper . . . . . . . . Mining . . . . . . . . . . . . – – – – 1 – – – 1 – 2 –

Idle . . . . . . . . . . . . . . – – – – 1 – – – – – 1 –

Dozer . . . . . . . . . Mining . . . . . . . . . . . . – – 1 – 1 – – – – – 2 –

Tractor . . . . . . . . Flame cutting/welding – – – – 1 1 – – – – 1 1

Excavator . . . . . . Mining . . . . . . . . . . . . – – 1 – – – – – – – 1 –

Total . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2 2 – 4 1 1 1 2 – 14 4

Ewhr,1

 106 hr . . . . . . . . . . . . . . . . . . . . 27 21 18 16 15 97

Irr2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.015 – 0.011 0.013 – 2

0.008 1

Derived from MSHA "Injury Experience in Mining" publications. 2

Calculated according to MSHA formula reported in the "Methodologies" section.

Fire brigades and fire departments fought the hydraulic

fluid/fuel fires with foam, dry chemical powder, and water. Two

pieces of equipment were destroyed or heavily damaged because

of failed fire suppression methods (table 11 and figure 5).

The two fires involving equipment with fire suppression

systems behaved as follows. In one instance, a fuel fire

involving a scraper burned out of control, although the operator

had performed dual activation of machine fire suppression and

engine shutoff systems. Evidently, the flow of fuel entrapped in

the lines continued to fuel the fire. In the second instance, a

hydraulic fluid/fuel fire involving an excavator burned out of

control because the operator had first tried to fight the fire with

portable fire extinguishers instead of activating the machine fire

suppression system.
12

Figure 5.—Major variables for mobile equipment fires at surface of underground coal mines, 1990-1999. (FE = portable fire extinguisher;

FSS = machine fire suppression system.)

Table 9.–Number of mobile equipment fires for surface of underground coal mines by ignition source,

 equipment involved, and time period, 1990-1999

Time period

Equipment Ignition source 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Highlift . . . . . . . . . Electrical short-battery explosion . . . . . . . . . . 1 – – – – 1

Hoist . . . . . . . . . . . Hydraulic fluid on equipment hot surfaces . . . 1 – – – – 1

Overheated oil 1 ....................... 1 – – – – 1

Loader . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces 2 – – – 1 3

Haulage truck . . . . Flame cutting/welding spark/slag 2 ......... – – – 1 – 1

Scraper . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces – – 2 – 1 3

Dozer . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces – 1 1 – – 2

Tractor . . . . . . . . . Flame cutting/welding spark/slag . . . . . . . . . . – – 1 – – 1

Excavator . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces – 1 – – – 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2 4 1 2 14 1

Due to compressor malfunction.

2

This source caused a hydraulic fluid fire.

Table 10.–Number of mobile equipment fires for surface of underground coal mines by method of detection,

equipment involved, and time period, 1990-1999

Time period

Equipment Method of detection 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Highlift . . . . . . . . Visual-smoke/explosion . . . 1 ––––1

Hoist . . . . . . . . . . Visual-smoke . . . . . . . . . . . 1 ––––1

Visual-flames/flash fire . . . . 1 ––––1

Loader . . . . . . . . Visual-flames/flash fire . . . . 2 –––13

Haulage truck . . . Visual-flames/flash fire .... – ––1–1

Scraper . . . . . . . . Visual-flames/flash fire . . . . – –1–12

Late detection-smoke . . . . . – –1––1

Dozer . . . . . . . . . Visual-flames/flash fire . . . . – 11––2

Tractor . . . . . . . . Visual-sparks . . . . . . . . . . . – –1––1

Excavator . . . . . . Visual-flames/flash fire . . . . – 1–––1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2 4 1 2 14
13

Table 11.–Number of mobile equipment fires for surface of underground coal mines by suppression method, 

equipment involved, and time period, 1990-1999

Time period

Equipment Suppression method 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Highlift . . . . . . . . Portable fire extinguisher ................. 1 – – – – 1

Hoist . . . . . . . . . . Water-foam-dry chemical powder-water1 ..... 1 – – – – 1

Portable fire extinguisher ................. 1 – – – – 1

Loader . . . . . . . . Water-foam-dry chemical powder1 .......... 2 – – – 1 3

Haulage truck . . . FE-foam-dry chemical powder-water1 ....... – – – 1 – 1

Scraper . . . . . . . . FSS-water-foam/dry chemical powder/HD2 ... – – 1 – – 1

FE-dry chemical powder-water . . . . . . . . . . . . . – – 1 – 1 2

Dozer . . . . . . . . . FE-water-foam/dry chemical powder1 ........ – 1 1 – – 2

Tractor . . . . . . . . FE/manual3 ............................ – – 1 – – 1

Excavator . . . . . . FE-FSS-HD . . . . . . . . . . . . . . . . . . . . . . . . . . . – 1 – – – 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2 4 1 2 14

FSS Machine fire suppression system.

FE Portable fire extinguisher.

HD Heavily damaged.

1

Methods used by fire brigades (mostly foam) and fire departments (mostly dry chemical powder). 2

Methods used by fire department and fire brigades following available FSS discharge by operator. 3

Methods used by welders to extinguish clothing or oxyfuel/grease fires (grease embedded in the equipment’s mechanical components). 4

Usually due to failed fire suppression methods.

Data during the five time periods, including the number of

fires and fire injuries, risk rates, and employees' working hours

according to the equipment involved and activity, are shown in

table 8 and partly illustrated in figure 3. Other variables such as

ignition source and methods of detection and suppression are

shown in tables 9-11.

Fires and injuries decreased slightly during most of the five

time periods; employees' working hours also declined (figure 3).

During 1990-1991, there were five fires and two injuries.

The equipment involved included loaders (two fires and one

injury), hoists (two fires and no injuries), and a highlift (one fire

and one injury) mostly during loading, hoisting, and lifting

activities. The Ewhr value was 27 × 106

 hr (Irr = 0.015). The

ignition sources were hydraulic fluid/fuel sprayed onto equipment hot surfaces, followed by overheated oil and electric

short/arcing. The most frequent methods of detection were

operators who saw flames/flash fires and operators/miners who

saw smoke. The most commonly used suppression methods

were foam, dry chemical powder, water, and portable fire

extinguishers.

During 1992-1993, there were two fires and no injuries. The

equipment involved included a dozer and an excavator (one fire

and no injuries for each) during mining activities. The Ewhr

value was 21 × 106

 hr. The ignition sources were hydraulic

fluid/fuel sprayed onto equipment hot surfaces. The fires, detected by the operators as flames/flash fires, were extinguished

with foam, dry chemical powder, and water (one equipment fire

was not extinguished). A machine fire suppression system was

discharged once.

During 1994-1995, there were four fires and one injury. The

equipment involved included scrapers (two fires and no injuries), a tractor (one fire and one injury), and a dozer (one fire

and no injuries) mostly during mining and flame cutting/welding

activities. The Ewhr value was 18 × 106

 hr (Irr = 0.011). The

ignition sources were hydraulic fluid/fuel sprayed onto equipment

hot surfaces and flame cutting/welding spark/slag. The fires

detected by the operator/welder as flames/flash fires or sparks

were extinguished with foam, dry chemical powder, and water

and by manual techniques (one equipment fire was not

extinguished). A machine fire suppression system was discharged

once.

During 1996-1997, there was only one fire and one injury.

The equipment involved was a haulage truck during flame

cutting/welding activities. During these activities, undetected

hot slag caused a hydraulic fluid fire. The Ewhr value was 16

× 106

 hr (Irr = 0.013).

During 1998-1999, there were two fires and no injuries. The

equipment involved included a loader and a scraper (one fire

and no injuries for each) during loading and mining activities.

The Ewhr value was 15 × 106

 hr. The ignition sources were

hydraulic fluid/fuel sprayed onto equipment hot surfaces. The

fires, detected by the operators as flames/flash fires, were

extinguished with foam, dry chemical, and water.

Table 12 shows the number of fire injuries per number of

equipment fires causing injuries and total fires by year, ignition

source, equipment involved, and location. In 1990, 1991, 1994,

and 1997, there were four fire injuries (one injury per year

caused by one fire per year). These involved highlifts, loaders,

tractors, and trucks during battery explosion, hydraulic

fluid/fuel, and flame cutting/welding fires.

MOBILE EQUIPMENT FIRES AT COAL

PREPARATION PLANTS

At coal prep plants, there were a total of 17 equipment fires

during 1990-1999; 7 injuries were caused by 6 of those fires

(table 13 and figure 6). One fire with one injury involved a

contractor. None of the equipment involved in the fires had

machine fire suppression systems.
14

Figure 6.—Mobile equipment fires and injuries for coal preparation plants by state, 1990-1999.

Table 12.–Number of fire injuries per number of mobile equipment fires causing injuries and total fires at surface of underground coal

mines by year, ignition source, equipment involved, and location, 1990-1999

Year No. fires

causing injuries

No. total

 fires

No. fire

injuries Ignition source Equipment Location

1990 . . . . 1 3 1 Battery explosion . . . . . . . . . . . . . . . . . . . . . . . . Highlift . . . Charging station.

1991 . . . . 1 2 1 Hydraulic fluid/fuel on equipment hot surfaces . . Loader . . . Loading area.

1992 .... – 1 – – – –

1993 .... – 1 – – – –

1994 . . . . 1 2 1 Flame cutting/welding spark/slag . . . . . . . . . . . . Tractor . . . Flame cutting/welding areas.1

1995 .... – 2 – – – –

1996 .... – – – – – –

1997 . . . . 1 1 1 Flame cutting/welding spark/slag . . . . . . . . . . . . Truck . . . . . Flame cutting/ welding areas.1

1998 .... – 1 – – – –

1999 .... – 1 – – – –

Total . . . . 4 14 4

1

Includes working and maintenance areas.

Table 13.–Number of mobile equipment fires, injuries, and risk rates for coal preparation

plants by state, equipment involved, and employees’ working hours, 1990-1999

State Equipment1 No. fires1 No. injuries1 Ewhr,2

 106 hr Irr3

IN . . . . . . . . Loader . . . . . . . . . . 1 – 8.3 –

KY . . . . . . . . Loader .......... 2 2

Truck . . . . . . . . . . . . 2 1 56.1 0.011

PA . . . . . . . . Loader .......... 1 –

Truck . . . . . . . . . . . . 1 – 34.6 –

VA . . . . . . . . Loader .......... 1 2

Truck . . . . . . . . . . . . 2 –

Dozer . . . . . . . . . . . 1 – 24 0.0167

WV . . . . . . . Loader .......... 2 1

Dozer . . . . . . . . . . . 2 –

Truck . . . . . . . . . . . . 2 1 60.6 0.0066

All other

states . . . . .

– – 57.2 –

Total . . . . . . . . . . . . . . . . . . . . . . . . 17 7 241 3

0.006 1

Derived from MSHA "Fire Accident Abstract" and "Fire Accident Report" publications. 2

Derived from MSHA "Injury Experience in Mining" publications. 3

Calculated according to MSHA formula reported in the "Methodologies" section.
15

The highest number of fires occurred in West Virginia (six

fires and two injuries), followed by Kentucky (four fires and

three injuries) and Virginia (four fires and two injuries).

Virginia had the highest injury risk rate (Irr = 0.0167). For coal

prep plants, the total Ewhr value was 241 × 106

 hr (Irr = 0.006)

(table 13).

The equipment involved, mostly during working activities,

included loaders (seven fires and five injuries), haulage/utility

trucks (seven fires and two injuries), and dozers (three fires and

no injuries) (table 14 and figure 7).

The ignition sources that caused most of the fires were

pressurized hydraulic fluid/fuel (7 fires or 41%) sprayed onto

equipment hot surfaces, followed by engine/mechanical

malfunctions, flammable liquid/ oil on hot surfaces, and electrical

short/arcing. Other sources were flame cutting/welding spark/slag

and heat sources (mostly heaters) (table 15 and figure 7).

Operators/miners/welders detected most of the fires when

they started as flames/flash fires, dim lights, smoke, or sparks

(table 16 and figure 7). One fire was detected late (which made

fire-fighting efforts ineffective), and two fires were undetected

and burned themselves out. Most of the hydraulic fluid/fuel

fires, although detected by the operators when they started, grew

out of control (requiring fire-fighting interventions at least once)

because of the continuous flow of fluids from pumps and tanks

due to engine shutoff failure, lack of an emergency line drainage

system, difficulty in reaching available emergency systems at

ground level, or lack of effective and rapid local fire-fighting

response capabilities. At least twice the cab was suddenly

engulfed in flames, forcing the operator to exit under difficult

conditions most likely due to the ignition of flammable vapors

and mists that formed and penetrated the cab.

Fire departments fought the hydraulic fluid/fuel fires with dry

chemical powder and water. Three pieces of equipment were

destroyed or heavily damaged because of late fire detection,

undetected fire, or fire size (table 17 and figure 7).

Data during the five time periods, including the number of

fires, injuries, risk rates, and employees' working hours according to the equipment involved and activity, are shown in

table 14 and partly illustrated in figure 3. Other variables such

as ignition source and methods of detection and suppression are

shown in tables 15-17.

The number of equipment fires shows small decreases during

most of the periods, accompanied by a decline in employees'

working hours. Injuries increased slightly during 1994-1995.

During 1990-1991, there were five fires and one injury. The

equipment involved included loaders (three fires and one injury)

and a haulage truck and dozer (one fire and no injuries for each)

during loading, haulage, and grading activities. The Ewhr value

was 60 × 106

 hr (Irr = 0.003). The ignition sources were hydraulic

fluid/fuel sprayed onto equipment hot surfaces, flammable

liquid/oil on hot surfaces, and heat sources. The most frequent

methods of detection were operators/miners who saw flames/flash

fires or smoke. (One fire was detected late, and one was

undetected). The most commonly used suppression methods were

portable fire extinguishers, dry chemical powder, and water.

During 1992-1993, there were four fires and one injury. The

equipment involved included loaders (two fires and one injury)

and a haulage truck and dozer (one fire and no injuries for each)

during loading and haulage activities. The Ewhr value was 51

× 106

 hr (Irr = 0.004). The ignition sources were hydraulic

fluid/fuel sprayed onto equipment hot surfaces, electrical

short/arcing, flammable liquid/ oil on hot surfaces, and engine

mechanical malfunctions. The most frequent methods of detection were operators who saw flames/flash fires and

operators/miners who saw smoke (one fire was undetected).

The most commonly used suppression methods were water, dry

chemical powder, and portable fire extinguishers.

During 1994-1995, there were three fires and four injuries.

The equipment involved included haulage/utility trucks (two

fires and two injuries) and a loader (one fire and two injuries)

during haulage and loading activities. The Ewhr value was 48

× 106

 hr (Irr = 0.017). The most common ignition sources were

hydraulic fluid/fuel sprayed onto equipment hot surfaces, followed by engine/mechanical malfunctions. The most frequent

methods of detection were operators/miners who saw

flames/flash fires or smoke. The most commonly used

suppression methods were water, dry chemical powder, and

portable fire extinguishers.

Table 14.–Number of mobile equipment fires, injuries, and risk rates for coal preparation plants by time period,

 equipment involved, activity, and employees’ working hours, 1990-1999

Equipment Activity

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No.

fires

No.

Injuries

No.

fires

No.

Injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires 

No.

injuries

No.

fires

No.

injuries

Loader ......... Loading ......... 2 1 2 1 1 2 – – 1 1 6 5

Idle . . . . . . . . . . . . 1 – – – – – – – – – 1 –

Dozer . . . . . . . . . . Grading . . . . . . . . . – – – – – – 1 – – – 1 –

Idle . . . . . . . . . . . . 1 – 1 – – – – – – – 2 –

Haulage/utility truck Flame cutting/

 welding.

1– – – –– –– –– 1 –

Haulage/utility .... – – 1 – 2 2 1 – 2 – 6 2

Total . . . . . . . . . . . . . . . . . . . . . . 5 1 4 1 3 4 2 – 3 1 17 7

Ewhr,1

 106 hr . . . . . . . . . . . . . . . . 60 51 48 44 39 241

Irr2 . . . . . . . . . . . . . . . . . . . . . . . . 0.003 0.004 0.017 – 0.005 2

0.006 1

Derived from MSHA "Injury Experience in Mining" publications. 2

Calculated according to MSHA formula reported in the "Methodologies" section.
16

Figure 7.—Major variables for mobile equipment fires at coal preparation plants, 1990-1999. (FE = portable fire extinguisher.)

Table 15.–Number of mobile equipment fires for coal preparation plants by ignition source, 

equipment involved, and time period, 1990-1999

Equipment Ignition source

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Loader . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces . . 2 1 1 – 1 5

Heat source . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 – – – – 1

Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . – 1 – – – 1

Dozer . . . . . . . . . . . . . Flammable liquid/fuel oil on hot surfaces . . . . . . 1 1 – 1 – 3

Haulage/utility truck . . Hydraulic fluid/fuel on equipment hot surfaces . . – – 1 – 1 2

Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . – – – – 1 1

Flame cutting/welding spark/slag . . . . . . . . . . . . 1 – – – – 1

Engine/mechanical malfunctions ............ – 1 1 1 – 3

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4 3 2 3 17

Table 16.–Number of mobile equipment fires for coal preparation plants by method of detection, 

equipment involved, and time period, 1990-1999

Equipment Method of detection

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Loader . . . . . . . . . . . . . Visual-flames/flash fire . . . 2 1 1 – 1 5

Visual-smoke . . . . . . . . . . – 1 – – – 1

Late detection-smoke . . . . 1 – – – – 1

Dozer . . . . . . . . . . . . . . Visual-flames/flash fire . . . – – – 1 – 1

Undetected ............ 1 1 – – – 2

Haulage/utility truck . . . Visual-flames/flash fire . . . – – 1 – 1 2

Visual-sparks . . . . . . . . . . 1 – – – – 1

Touch-hot surface . . . . . . . – – 1 – – 1

Visual-smoke . . . . . . . . . . – 1 – 1 – 2

Visual-dim lights . . . . . . . . – – – – 1 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4 3 2 3 17
17

During 1996-1997, there were two fires and no injuries. The

equipment involved included a haulage truck and a dozer during

haulage and grading activities. The Ewhr value was 44 × 106

 hr.

The ignition sources were flammable liquid/oil on hot surfaces

and engine/mechanical malfunctions. The methods of detection

were miners/operators who saw flames or smoke. The

suppression methods used were portable fire extinguishers.

During 1998-1999, there were three fires and one injury. The

equipment involved included haulage/utility trucks (two fires

and no injuries) and a loader (one fire and one injury) during

haulage and loading activities. The Ewhr value was 39 × 106

 hr

(Irr = 0.005). The ignition sources were hydraulic fluid/fuel

sprayed onto equipment hot surfaces and electrical short/arcing.

The fires, which were detected by the operators/miners as

flames/flash fires, dim lights, or sparks, were extinguished with

water, dry chemical powder, and portable fire extinguishers.

Table 18 shows the number of fire injuries per number of

fires causing injuries and total fires by year, ignition source,

equipment involved, and location. The highest number of injuries was recorded in 1995 (four fire injuries caused by three

equipment fires). These involved loaders and trucks during

hydraulic fluid/fuel and mechanical malfunction fires.

MOBILE EQUIPMENT FIRES IN UNDERGROUND

COAL MINES

In underground coal mines, there were a total of 26 equipment

fires during 1990-1999; 10 of those fires caused 10 injuries (table

19 and figure 8). One fire with one injury involved a contractor.

In all, three pieces of equipment (12%) had machine fire suppression systems. These are required by law on all underground

diesel equipment and electrically powered mine face equipment

using non-fire-resistant hydraulic fluids.

The highest number of fires occurred in Kentucky (six fires

and two injuries), followed by Alabama (five fires and two

injuries), Virginia and Pennsylvania (four fires and one injury

for each state), and West Virginia (three fires and two injuries).

Alabama had the highest fire and injury risk rates (Frr = 0.03;

Irr = 0.006). For underground coal mines, the total Ewhr value

was 1,003 × 106

 hr (Irr = 0.002); the CP value was 4,008 × 106

st (Frr = 0.007) (table 19).

The equipment involved, mostly during working activities, included scoops (six fires and three injuries), shuttle cars (five fires and

three injuries), roof bolters (five fires and two injuries), and

continuous miners (three fires and no injuries) (table 20 and figure 9).

The ignition sources that caused most of the underground

equipment fires were electrical short/arcing (13 fires or 50%).

At least once, an electrical fire spread to the hydraulic lines,

(most underground equipment is electrically powered). Other

ignition sources were flame cutting/welding spark/slag,

refueling fuel on hot surfaces, mechanical malfunction/friction,

heat source, hydraulic fluid sprayed onto equipment hot

surfaces, and overheated oil (table 21 and figure 9).

Operators/miners/ welders detected most of the fires when they

started as flames, smoke, or sparks. One fire was detected by a

conveyor belt entry carbon monoxide (CO) sensor alarm after

the fire had started, and three were detected late (which made

fire-fighting methods ineffective) (table 22 and figure 9). Upon

mine/section evacuation, mine rescue teams (required five

times), which were often severely hindered by intense smoke in

trying to reach the fire location, fought three electrical fires, one

hydraulic fluid fire, and one heat source fire with rock dust, dry

chemical powder, and water. Four pieces of equipment were

destroyed or heavily damaged because of failed fire suppression

methods and late fire detection (table 23 and figure 9).

The three fires involving equipment with fire suppression

systems behaved as follows. In two instances, a hydraulic fluid

fire and an electrical fire involving two bolters were temporarily

contained upon dual activation of the fire suppression/motor

deenergization systems; portable fire extinguishers and water

were used to complete the extinguishment. In the third instance,

an electrical fire involving a scoop, detected by a conveyor belt

entry CO sensor alarm long after the fire had started, raged out

of control and spread to the hydraulic lines because of machine

fire suppression system failure (clogged hoses).

Table 17.–Number of mobile equipment fires for coal preparation plants by suppression method,

equipment involved, and time period, 1990-1999

Time Period

Equipment Suppression method 90-91

No. fires

92-93

No. fires

94-95

No. fires

96-97

No. fires

98-99

No. fires

90-99

No. fires

Loader . . . . . . . . . . . . . . FE-water-dry chemical powder1 ..... 2 1 1 –1 5

Destroyed/heavily damaged2 ....... 1 – – –– 1

Portable fire extinguisher .......... – 1 – –– 1

Dozer . . . . . . . . . . . . . . . Water-dry chemical powder1 ........ – – – 1– 1

Destroyed/heavily damaged2 ....... 1 1 – –– 2

Haulage/utility truck . . . . FE-water-dry chemical powder1 ..... – – 1 –1 2

FE-water . . . . . . . . . . . . . . . . . . . . . . . – – 1 –– 1

Portable fire extinguisher .......... – 1 – 11 3

Manual3 ........................ 1 – – –– 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4 3 2 3 17

FE Portable fire extinguisher.

1

Methods mostly used by fire departments.

2

Usually due to late fire detection, undetected fires or fire size. 3

Methods used by welders to extinguish clothing fires.
18

Figure 8.—Mobile equipment fires and injuries for underground coal mines by state, 1990-1999.

Figure 9.—Major variables for mobile equipment fires in underground coal mines, 1990-1999. (FE = portable fire extinguisher; FSS =

machine fire suppression system.)
19

Table 18.–Number of fire injuries per number of mobile equipment fires causing injuries and total fires

at coal preparation plants by year, ignition source, equipment involved, and location, 1990-1999

Year

No. fires

causing

injuries

No. total

fires

No. fire

injuries Ignition source Equipment Location

1990 .... – 4 – – – –

1991 . . . . 1 1 1 Hydraulic fluid/fuel on equipment hot

 surfaces.

Loader ........ Loading area.

1992 .... – 1 – – – –

1993 . . . . 1 3 1 Hydraulic fluid/fuel on equipment hot

 surfaces.

Loader ........ Loading area.

1994 .... – – – – – –

1995 . . . . 2 3 3 Hydraulic fluid/fuel on equipment hot

 surfaces.

Loader–truck .... Loading/haulage areas.

1 – 1 Mechanical malfunction . . . . . . . . . . Truck . . . . . . . . . . Maintenance area.

1996 .... – – – – – –

1997 .... – 2 – – – –

1998 .... – – – – – –

1999 . . . . 1 3 1 Hydraulic fluid/fuel on equipment hot

 surfaces.

Loader ........ Loading area.

Total . . . . 6 17 7

Table 19.–Number of mobile equipment fires, injuries, and risk rates for underground coal mines by state, 

equipment involved, coal production, and employees’ working hours, 1990-1999

State1 Equipment1 No. fires1 No. injuries1 Ewhr,2

 106 hr CP,2 106 st Irr3 Frr3

AL . . . . . Bolter . . . . . . . . . . . . 1 1

Scoop . . . . . . . . . . . . 1 1

Shuttle car . . . . . . . . 1 –

Continuous miner . . . 1 –

Shearer . . . . . . . . . . . 1 – 67.1 165.1 0.006 0.03

CO . . . . Scoop . . . . . . . . . . . . 1 1 20.1 148.2 0.01 0.007

IL . . . . . . Scoop . . . . . . . . . . . . 1 –

Shuttle car . . . . . . . . 1 1 96.6 404.5 0.002 0.005

KY . . . . . Scoop . . . . . . . . . . . . 2 1

Continuous miner . . . 1 –

Bolter . . . . . . . . . . . . 1 –

Golf cart . . . . . . . . . . 1 –

Railrunner ......... 1 1 245.6 949.5 0.0016 0.0063

PA . . . . . Scoop . . . . . . . . . . . . 1 –

Truck . . . . . . . . . . . . . 1 –

3-wheeler ......... 1 –

Jeep . . . . . . . . . . . . . 1 1 124.5 455.4 0.0016 0.009

UT . . . . . Continuous miner . . . 1 – 34.3 241 – 0.0042

VA . . . . . Shearer ........... 1 –

Shuttle car . . . . . . . . 2 1

Bolter . . . . . . . . . . . . 1 – 96 291.4 0.002 0.014

WV . . . . Bolter . . . . . . . . . . . . 2 1

Shuttle car . . . . . . . . 1 1 281.5 1,156.2 0.0014 0.0026

All other

states . .

– – – 37.6 196.7

Total . . . . . . . . . . . . . . . . . . . 26 10 1,003 4,008 3

0.002 30.007 1

Derived from MSHA "Fire Accident Abstract" and "Fire Accident Report" publications. 2

Derived from MSHA "Injury Experience in Mining" publications. 3

Calculated according to MSHA and USBM formulas reported in the "Methodologies" section.
20

Table 20.–Number of mobile equipment fires, injuries, and risk rates for underground coal mines by time period, 

equipment involved, activity, and employees’ working hours, 1990-1999

Equipment Activity

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires 

No.

injuries

No.

fires

No.

injuries

Scoop . . . . . . . . . Mucking . . . . . . . . . . – – – – 3 1 – – 1 – 4 1

Flame cutting/welding 1 1 – – – – – – 1 1 2 2

Continuous miner Mining ............ 2 – – – – – – – – – 2 –

Flame cutting/welding 1 – – – – – – – – – 1 –

Shearer . . . . . . . . Mining . . . . . . . . . . . . 2 – – – – – – – – – 2 –

Bolter . . . . . . . . . Bolting . . . . . . . . . . . – – 2 1 – – – – 2 – 4 1

Flame cutting/welding 1 1 – – – – – – – – 1 1

Shuttle car . . . . . Maintenance ....... 1 1 1 – 2 1 – – 1 1 5 3

Railrunner . . . . . . Transportation . . . . . – – 1 1 – – – – – – 1 1

Golf cart . . . . . . . Maintenance ....... – – – – 1 – – – – – 1 –

Haulage truck . . . Haulage .......... – – 1 – – – – – – – 1 –

3–Wheeler . . . . . Idle . . . . . . . . . . . . . . – – – – – – 1 – – – 1 –

Jeep . . . . . . . . . . Idle . . . . . . . . . . . . . . – – – – 1 1 – – – – 1 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3 5 2 7 3 1 – 5 2 26 10

Ewhr,1

 106 hr . . . . . . . . . . . . . . . . . . . . . 257 209 196 179 162 1,003

Irr2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.0023 0.002 0.0031 – 0.0025 2

0.002

CP,1

 106 st . . . . . . . . . . . . . . . . . . . . . . . 824 752 792 830 810 4,008

Frr2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.01 0.007 0.009 0.001 0.006 3

0.007 1

Derived from MSHA "Injury Experience in Mining" publications. 2

Calculated according to MSHA and USBM formula reported in the "Methodologies" section.

Table 21.–Number of mobile equipment fires for underground coal mines by ignition source, 

equipment involved, and time period, 1990-1999

Equipment Ignition source

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Scoop . . . . . . . . . . . . Electrical short/arcing1 ............... – – 1 – – 1

Flame cutting/welding spark/slag . . . . . . . 1 – – – 1 2

Electrical short/arcing . . . . . . . . . . . . . . . . – – 2 – 1 3

Continuous miner . . . Mechanical friction .................. 1 – – – – 1

Flame cutting/welding spark/slag . . . . . . . 1 – – – – 1

Fuel oil on hot surfaces . . . . . . . . . . . . . . 1 – – – – 1

Shearer . . . . . . . . . . . Mechanical malfunction .............. 1 – – – – 1

Overheated oil2 ..................... 1 – – – – 1

Bolter . . . . . . . . . . . . Hydraulic fluid on equipment hot surfaces – 1 – – – 1

Flame cutting/welding spark/slag . . . . . . . 1 – – – – 1

Electrical short/arcing . . . . . . . . . . . . . . . . – 1 – – 2 3

Shuttle car . . . . . . . . Refueling fuel on hot surfaces . . . . . . . . . 1 1 – – – 2

Electrical short/arcing . . . . . . . . . . . . . . . . – – 2 – – 2

Heat source . . . . . . . . . . . . . . . . . . . . . . . – – – – 1 1

Golf cart . . . . . . . . . . Electrical short/arcing . . . . . . . . . . . . . . . . – – 1 – – 1

Haulage truck . . . . . . Electrical short/arcing . . . . . . . . . . . . . . . . – 1 – – – 1

3–wheeler . . . . . . . . . Electrical short/arcing . . . . . . . . . . . . . . . . – – – 1 – 1

Jeep . . . . . . . . . . . . . Heat source . . . . . . . . . . . . . . . . . . . . . . . – – 1 – – 1

Railrunner . . . . . . . . . Electrical short/arcing . . . . . . . . . . . . . . . . – 1 – – – 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5 7 1 5 2 1

This source caused a hydraulic fluid fire. 2

Due to compressor malfunction.

Data during the five time periods, including the number of

fires, fire injuries, risk rates, employees' working hours, and coal

production according to the equipment involved and activity, are

shown in table 20 and partly illustrated in figure 3. Other

variables such as ignition source and methods of detection and

suppression are shown in tables 21-23.

Equipment fires and fire injuries decreased during 1996-

1997, then increased during 1998-1999, accompanied by a sharp

decline in employees' working hours and small changes in coal

production.

During 1990-1991, there were eight fires and three injuries.

The equipment involved included continuous miners (three fires

and no injuries), shearers (two fires and no injuries), and a bolter

and shuttle car (one fire and injury for each) during mining,

maintenance, and flame cutting/welding activities. The Ewhr

value was 257 × 106

 hr (Irr = 0.002); the CP value was 824

× 106

 st (Frr = 0.01). The most common ignition sources were

flame cutting/welding spark/slag, followed by mechanical friction/

malfunction and refueling fuel/fuel oil on hot surfaces. The
21

Table 22.–Number of mobile equipment fires for underground coal mines by method of detection, 

equipment involved, and time period, 1990-1999

Time period

Equipment Method of detection 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Scoop . . . . . . . . . . . . Visual-flames/flash fire . ––1––1

Visual-sparks . . . . . . . . 1–––12

Late detection-CO alarm – – 1 – – 1

Visual-smoke . . . . . . . . ––1–12

Continuous miner . . . Visual-smoke ........ 2––––2

Visual-sparks . . . . . . . . 1––––1

Shearer . . . . . . . . . . . Visual-flames/flash fire . 1––––1

Visual-smoke . . . . . . . . 1––––1

Bolter . . . . . . . . . . . . Visual-sparks . . . . . . . . 1––––1

Visual-smoke . . . . . . . . –1–––1

Undetected .......... ––––11

Power loss . . . . . . . . . . ––––11

Late detection–smoke . –1–––1

Shuttle car . . . . . . . . Visual-flames/flash fire . 11–––2

Late detection-smoke . . – – 1 – – 1

Visual-smoke . . . . . . . . ––1––1

Touch-hot spot . . . . . . . ––––11

Golf cart . . . . . . . . . . Visual-smoke . . . . . . . . ––1––1

Haulage truck . . . . . . Visual-smoke . . . . . . . . –1–––1

3-wheeler . . . . . . . . . Late detection-smoke . . –––1–1

Jeep . . . . . . . . . . . . . Late detection-smoke . . ––1––1

Railrunner . . . . . . . . . Visual-sparks . . . . . . . . –1–––1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5 7 1 5 26

Table 23.–Number of mobile equipment fires for underground coal mines by suppression method, 

equipment involved, and time period, 1990-1999

Time period

Equipment Suppression method 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Scoop . . . . . . . . . . . . . FE/manual1 ............................ 1 – – – 1 2

FE-rockdust-dry chemical powder-water2 ..... – – 2 – 1 3

Destroyed/heavily damaged3 .............. – – 1 – – 1

Continuous miner . . . . FE-WSS2 ............................. 2 – – – – 2

Portable fire extinguisher ................. 1 – – – – 1

Shearer . . . . . . . . . . . . FE-WSS2 ............................. 1 – – – – 1

Portable fire extinguisher ................. 1 – – – – 1

Bolter . . . . . . . . . . . . . FE-water-dry chemical powder2 ............ – – – – 1 1

FE/manual1 ............................ 1 1 – – – 2

FE-FSS-water-dry chemical powder4 ........ – 1 – – 1 2

Shuttle car . . . . . . . . . FE-rockdust-dry chemical powder-water2 ..... – 1 – – – 1

Destroyed/heavily damaged3 .............. – – 1 – – 1

FE/manual1 ............................ 1 – 1 – 1 3

Golf cart . . . . . . . . . . . Portable fire extinguisher ................. – – 1 – – 1

Haulage/utility truck . . Portable fire extinguisher ................. – 1 – – – 1

3-wheeler . . . . . . . . . . Portable fire extinguisher ................. – – – 1 – 1

Jeep . . . . . . . . . . . . . . FE-dry chemical powder-water2 ............ – – 1 – – 1

Railrunner . . . . . . . . . . FE-dry chemical powder-water2 ............ – 1 – – – 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5 7 1 5 26

FE Portable fire extinguisher.

FSS Machine fire suppression system.

WSS Machine water spray.

1

Methods used by welders to extinguish clothing or oxyfuel/grease fires (grease embedded in the equipment’s mechanical components). 2

Method used by mine rescue teams following, at times, machine water spray discharge by operator. 3

Usually due to failed fire suppression methods (one FSS failure) or late detection. 4

Methods used by mine rescue teams following available FSS discharge by operator.

methods of detection were welders/operators who saw sparks,

smoke, or flames. The suppression methods were manual methods, portable fire extinguishers, and machine water sprays.

During 1992-1993, there were five fires and two injuries.

The equipment involved included bolters (two fires and one

injury), a railrunner (one fire and one injury), and a truck and a

shuttle car (one fire and no injuries for each) during bolting,

transportation, and haulage activities. The Ewhr value was 209

× 106

 hr (Irr = 0.002); the CP value was 752 × 106 st (Frr

= 0.007). The ignition sources were electrical short/arcing,
22

followed by hydraulic fluid sprayed onto equipment hot surfaces

and refueling fuel on hot surfaces. The methods of detection

were operators who saw smoke or flames/flash fires (one fire

was detected late). The suppression methods used were portable

fire extinguishers, rock dust, and dry chemical powder. A

machine fire suppression system was discharged once.

During 1994-1995, there were seven fires and three injuries.

The equipment involved included scoops (three fires and one

injury), shuttle cars (two fires and one injury), a jeep (one fire

and one injury), and a golf cart (one fire and no injuries) mostly

during mucking and maintenance activities. The Ewhr value

was 196 × 106

 hr (Irr = 0.003); the CP value was 792 × 106 st

(Frr = 0.009). The ignition sources were electrical/short/arcing,

followed by heat sources. The most frequent methods of detection were operators who saw smoke or flames/flash fires

three fires were detected late; (one of these fires was detected

late by a conveyor belt entry CO sensor alarm). The most

commonly used suppression methods were portable fire

extinguishers, dry chemical powder, rock dust, and water.

A machine fire suppression system failed to discharge because

of clogged hoses.

During 1996-1997, there was one fire and no injuries involving a three-wheeler. The electrical fire was detected late as

smoke; it was extinguished with dry chemical powder. The Ewhr

value was 179 × 106

 hr; the CP value was 830 × 106 st (Frr

= 0.001).

During 1998-1999, there were five fires and two injuries.

The equipment involved included scoops (two fires and one

injury), bolters (two fires and no injuries), and a shuttle car

(one fire and one injury) during mucking, bolting, flame

cutting/welding, and maintenance activities. The Ewhr value

was 162 × 106

 hr (Irr = 0.003); the CP value was 810 × 106 st

(Frr = 0.006). The ignition sources were electrical short/arcing,

followed by heat sources and flame cutting/welding spark/slag.

The most frequent methods of detection were operators/miners

who saw smoke or flames or experienced power loss and

welders who saw sparks (one fire was undetected). The most

commonly used suppression methods were portable fire

extinguishers, dry chemical powder, rock dust, and water. A

machine fire suppression system was discharged once.

Table 24 shows the number of fire injuries per number of fires

causing injuries and total fires by year, ignition source, equipment

involved, and location. The highest number of fire injuries was

recorded in 1994 (two fire injuries caused by two equipment fires)

during electrical fires involving a scoop and a shuttle car.

Table 24.–Number of fire injuries per number of mobile equipment fires causing injuries and total fires

in underground coal mines by year, ignition source, equipment involved, and location, 1990-1999

Year No. fires

causing injuries

No. total

fires

No. fire

injuries Ignition source Equipment Location

1990 . . . 1 6 1 Flame cutting/welding spark/slag . . . . Scoop . . . . . . . . . . . . Flame cutting/welding areas.1

1991 . . . 1 2 1 Refueling fuel on hot surfaces . . . . . . Shuttle car . . . . . . . . Transport area.

1 – 1 Flame cutting/welding spark/ slag . . . Bolter . . . . . . . . . . . . Flame cutting/welding areas.1

1992 . . . 1 3 1 Electrical short/arcing . . . . . . . . . . . . . Railrunner . . . . . . . . . Rail track area.

1993 . . . 1 2 1 Electrical short/arcing . . . . . . . . . . . . . Bolter . . . . . . . . . . . . Bolting area.

1994 . . . 2 2 2 Electrical short/arcing . . . . . . . . . . . . . Scoop/shuttle car . . . Mining face/charging station.

1995 . . . 1 5 1 Heat source . . . . . . . . . . . . . . . . . . . . Jeep . . . . . . . . . . . . . Crosscut section.

1996 . . . – – – – – –

1997 . . . – 1 – – – –

1998 . . . – – – – – –

1999 . . . 1 5 1 Flame cutting/welding spark/ slag . . . Scoop . . . . . . . . . . . . Flame cutting/welding areas.1

1 - 1 Heat source . . . . . . . . . . . . . . . . . . . . Shuttle car . . . . . . . . Maintenance area.

Total . . . 10 26 10

1

Includes headgate, bolting, and mining areas.

MOBILE EQUIPMENT DATA ANALYSIS FOR ALL METAL/NONMETAL 

MINING CATEGORIES

MOBILE EQUIPMENT FIRES AT SURFACE

METAL/NONMETAL MINES

At surface metal/nonmetal mines, there were a total of 49

equipment fires during 1990-1999; 24 of those fires caused

24 injuries and 1 fatality (table 25 and figure 10). Six

equipment fires with five injuries occurred at metal mines.

Forty-three fires with nineteen injuries and one fatality occurred

at nonmetal mines. Seven fires with five injuries involved

contractors. In all, five pieces of equipment (10%) had machine

fire suppression systems.

The highest number of equipment fires occurred in Nevada (15

fires, 7 injuries, and 1 fatality), followed by Arizona (14 fires

and 8 injuries), Minnesota (8 fires and 3 injuries), and California

(3 fires and no injuries). Minnesota had the highest injury risk

rate (Irr = 0.014). For surface metal/nonmetal mines, the total

Ewhr value was 467 × 106

 hr (Irr = 0.01) (table 25).

The equipment involved, mostly during working activities,

included haulage/utility trucks (23 fires, 15 injuries, and 1

fatality), shovels (14 fires and 2 injuries), drills (5 fires and no

injuries) and loaders (4 fires and 5 injuries) (table 26 and figure

11).
23

Table 25.–Number of mobile equipment fires, injuries, and risk rates for surface

metal/nonmetal mines by state, equipment involved, and employees’ 

working hours, 1990-1999

State1 Equipment1 No. fires1 No. injuries1 Ewhr,2

 106 hr Irr3

AK . . . . . . Shovel . . . . . . . . 2 – 9.2 –

AL . . . . . . Scraper . . . . . . . . 1 1 1.5 0.13

AZ . . . . . . Truck . . . . . . . . . . 8 6

Shovel . . . . . . . . 5 1

Loader . . . . . . . . 1 1 80 0.015

CA . . . . . . Shovel . . . . . . . . 1 –

Truck . . . . . . . . . . 1 –

Excavator . . . . . . 1 – 13 –

FL . . . . . . Loader ........ 1 1

Truck . . . . . . . . . . 1 1 33.4 0.012

GA . . . . . Truck . . . . . . . . . . 1 1 14.5 0.014

ID . . . . . . Shovel . . . . . . . . 1 – 7.5 –

MN . . . . . Truck . . . . . . . . . . 3 2

Loader ........ 1 1

Shovel . . . . . . . . 1 –

Drill . . . . . . . . . . . 3 – 42.5 0.014

MO . . . . . Shovel . . . . . . . . 1 1 0.7 0.3

NV4 . . . . . Truck . . . . . . . . . . 8 4

Drill . . . . . . . . . . . 2 –

Shovel . . . . . . . . 3 –

Dozer . . . . . . . . . 1 1

Loader . . . . . . . . 1 2 11.4 0.123

SC . . . . . . Truck . . . . . . . . . . 1 1 0.7 0.3

All other states . . . . . . . . . . . . . – – 252.2 –

Total . . . . . . . . . . . . . . . . . 49 24 467 3

0.01 1

Derived from MSHA "Fire Accident Abstract" and "Fire Accident Report" publications. 2

Derived from MSHA "Injury Experience in Mining" publications. 3

Calculated according to MSHA formula reported in the "Methodologies" section. 4

Nevada had one fire fatality.

Table 26.–Number of mobile equipment fires, injuries, fatalities, and risk rates for surface metal/nonmetal mines

by time period, equipment involved, activity, and employees’ working hours, 1990-1999

Equipment Activity

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires 

No.

Injuries

No.

fires

No.

Injuries

Haulage/utility truck1 Haulage/utility . . . . . . 4 3 3 2 6 3 7 4 - – 20 12

Maintenance ....... – – 1 1 – – – – 1 1 2 2

Flame cutting/welding – – – – – – – – 1 1 1 1

Scraper . . . . . . . . . . Mining . . . . . . . . . . . . – – 1 1 – – – – – – 1 1

Excavator . . . . . . . . Mining . . . . . . . . . . . . – – 1 – – – – – – – 1 –

Shovel . . . . . . . . . . Mining . . . . . . . . . . . . 1 – 4 – 1 – 2 – – – 8 –

Flame cutting/welding – – 2 1 1 1 – – – – 3 2

Idle . . . . . . . . . . . . . . 1 – 2 – – – – – – – 3 –

Loader .......... Loading ........... 2 3 2 2 – – – – – – 4 5

Drill . . . . . . . . . . . . . Idle . . . . . . . . . . . . . . – – – – 1 – – – – – 1 –

Drilling ........... – – 1 – 2 – 1 – – – 4 –

Dozer . . . . . . . . . . . Mining . . . . . . . . . . . . 1 1 – – – – – – – – 1 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 7 17 7 11 4 10 4 2 2 49 24

No. fatalities . . . . . . . . . . . . . . . . . . . . . – – 1 – – 1

Ewhr,2

 106 hr . . . . . . . . . . . . . . . . . . . . . 97 93 95 98 84 467

Irr3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.014 0.015 0.008 0.008 0.005 3

0.01 1

This equipment caused one fire fatality.

2

Derived from MSHA "Injury Experience in Mining" publications. 3

Calculated according to MSHA formula reported in the "Methodologies" section.
24

Figure 10.—Mobile equipment fires and injuries for surface metal/nonmetal mines by state, 1990-1999.

Figure 11.—Major variables for mobile equipment fires at surface metal/nonmetal mines, 1990-1999. (FE = portable fire extinguisher;

FSS = machine fire suppression system.)

Most of the fires were caused by pressurized hydraulic

fluid/fuel (33 fires or 67%) sprayed onto equipment hot surfaces, followed by flame cutting/welding spark/slag, flammable

liquid/refueling fuel/oil on hot surfaces, flame cutting/welding

spark/slag, and electrical short/arcing. Other sources were heat

sources and overheated oil (table 27 and figure 11). Operators/

miners/welders detected most of the fires when they started as

flames/flash fires, smoke, power loss, or sparks. Most of the

hydraulic fluid/fuel fires, although detected by the operators

when they started, grew out of control (requiring at least one

firefighter intervention) because of the continuous flow of fluids

from pumps and tanks due to engine shutoff failure, lack of an

emergency line drainage system, difficulty in reaching available

emergency systems at ground level due to flames engulfing the

area, or lack of effective and rapid local fire-fighting response

capabilities. Four fires were detected late (which made firefighting methods ineffective), and one was undetected and

burned itself out (table 28 and figure 11). At least twice the cab
25

was suddenly engulfed in flames, forcing the operator to exit the

cab under difficult conditions (one fatality) most likely due to

the ignition of flammable vapors and mists that formed and

penetrated the cab during the spraying of hydraulic fluid/fuel

onto equipment hot surfaces.

Fire brigades and fire departments, handicapped by travel

distances, fought the hydraulic fluid/fuel fires with foam (mostly

used by fire brigades), dry chemical powder (mostly used by fire

departments), and water. Seven pieces of equipment were destroyed or heavily damaged because of failed fire suppression and

fire-fighting methods, late fire detection, undetected fires, or fire

size, (table 29 and figure 11).

The five hydraulic fluid fires that involved equipment with

fire suppression systems behaved as follows. In the first

instance, which involved a loader, the fire abated temporarily

upon ground-level dual activation of the fire suppression and

engine shutoff systems. In the second and third instances, the

fires, which involved a shovel and haulage truck, raged out of

control because, upon activation of machine fire suppression

systems, the operators failed to shut off the engine because of

advancing flames. In the fourth instance, which involved an idle

shovel, the fire raged out of control because of late detection

and failure to activate the machine fire suppression system due

to fire size. In the fifth instance, which involved a haulage truck

wheel motor, the hydraulic fluid fire raged out of control

because the operator (one fatality), unaware of the automatic fire

suppression system self-activation (which occurred at a preset

temperature of 356 °F) due to unclear cab signals, continued to

operate the rig until the flames suddenly engulfed the cab.

Data during the five time periods, including the number of

fires, fire injuries and fire fatality, risk rates, and employees'

working hours according to the equipment involved and activity,

are shown in table 26 and partly illustrated in figure 12. Other

variables such as ignition source and methods of detection and

suppression are shown in tables 27-29.

Equipment fires increased sharply during 1992-1993 (the

number of fire injuries stayed steady during this period), then

decreased during subsequent periods, accompanied by a small

decline in employees' working hours.

During 1990-1991, there were nine fires and seven injuries.

The equipment involved included haulage/utility trucks (four

fires and three injuries), loaders (two fires and three injuries),

and shovels (two fires and no injuries) mostly during haulage,

loading, and mining activities. The Ewhr value was 97 × 106

 hr

(Irr = 0.014). The ignition sources were hydraulic fluid/fuel

sprayed onto equipment hot surfaces, followed by electrical

short/arcing and flammable liquid/refueling fuel/oil on hot

surfaces. The methods of detection were operators who saw

flames/flash fires and operators/miners who saw smoke (one fire

was detected late). The suppression methods used were portable

fire extinguishers, foam, dry chemical powder, and water (one

equipment fire was not extinguished). A machine fire suppression system was discharged once; in another instance, the

system was not activated.

During 1992-1993, there were 17 fires and 7 injuries. The

equipment involved included shovels (eight fires and one

injury), haulage/utility trucks (four fires and three injuries), and

loaders (two fires and two injuries) mostly during mining,

haulage, and loading activities. The Ewhr value was 93 × 106

hr (Irr = 0.015). The most common ignition sources were hydraulic fluid/fuel sprayed onto equipment hot surfaces, followed

by flame cutting/welding spark/slag, electrical short/arcing, and

flammable liquid/refueling fuel/oil on hot surfaces (one fire was

detected late and one fire was undetected). The most frequent

methods of detection were operators who saw flames/flash fires,

followed by miners/welders who saw smoke or sparks. The

most commonly used suppression methods were portable fire

extinguisher, foam, dry chemical powder, and water (three

equipment fires were not extinguished). A machine fire suppression system was discharged once.

During 1994-1995, there were 11 fires, 4 injuries, and

1 fatality. The equipment involved included haulage/utility

trucks (six fires, three injuries, and one fatality), drills (three

fires and no injuries), and shovels (two fires and one injury)

mostly during haulage, drilling, and mining activities. The

Ewhr value was 95 × 106

 hr (Irr = 0.008). The most common

ignition sources were hydraulic fluid/fuel sprayed onto

equipment hot surfaces, followed by electrical short/arcing, heat

sources, and flame cutting/welding spark/slag. The most

frequent methods of detection were operators who saw

flames/flash fires or experienced power loss and

operators/miners/welders who saw smoke or sparks. The most

commonly used suppression methods were portable fire

extinguishers, foam, and dry chemical powder (two equipment

fires were not extinguished). The machine fire suppression

systems were discharged twice.

During 1996-1997, there were 10 fires and 4 injuries. The

equipment involved included haulage/utility trucks (seven fires

and four injuries), shovels (two fires and no injuries), and drills

(one fire and no injuries) mostly during haulage, mining, and

drilling activities. The Ewhr value was 98 × 106

 hr (Irr

= 0.008). The ignition sources were hydraulic fluid/fuel sprayed

onto equipment hot surfaces, followed by electrical short/arcing,

heat sources, and flammable liquid/refueling fuel/oil on hot

surfaces. The methods of detection were operators who saw

flames/flash fires and operators/miners who saw smoke. The

most commonly used suppression methods were portable fire

extinguishers, foam, dry chemical powder, and water (one

equipment fire was not extinguished).

During 1998-1999, there were two fires and two injuries.

The equipment involved included haulage/utility trucks (two

fires and two injuries) during maintenance and flame

cutting/welding activities. The Ewhr value was 84 × 106

 hr (Irr

= 0.005). The ignition sources were flammable liquids on hot

surfaces and flame cutting/welding spark/slag. The methods of

detection were operators/miners who saw flames/flash fires and

welders who saw sparks. The suppression methods used were

portable fire extinguishers.
26

Table 30 shows the number of fire injuries per number of

fires causing injuries and total fires by year, ignition source,

equipment involved, and location. The highest number of fire

injuries was recorded in 1995 (two fire injuries and one fire

fatality caused by three equipment fires); these involved trucks

during hydraulic fluid/fuel and flammable liquid fires. The fire

fatality, which occurred in Nevada during a hydraulic fluid fire

involving a haulage truck wheel motor, was caused by flames

engulfing the cab. The operator, who was unaware of the automatic fire suppression system activation due to unclear signals,

had continued to operate the rig [MSHA 1995f].

MOBILE EQUIPMENT FIRES AT SURFACE SAND

AND GRAVEL AND STONE MINES

At surface sand and gravel and stone mines, there were a

total of 46 equipment fires during 1990-1999; 35 injuries and

1 fatality were caused by 36 of those fires (table 31 and figure

13). Nineteen fires with fifteen injuries occurred at sand and

gravel mines. Twenty-seven fires with twenty injuries and one

fatality occurred at stone mines. Three fires with three injuries

involved contractors. None of the equipment involved in the

fires had machine fire suppression systems.

The highest number of equipment fires and fire injuries

occurred in Pennsylvania (six fires and five injuries), followed

by California (six fires and four injuries) and Michigan (five

fires and two injuries). Pennsylvania had the highest injury risk

rate (Irr = 0.017). For surface sand and gravel and stone mines,

the total Ewhr value was 1,101 × 106

 hr (Irr = 0.006) (table 31).

The equipment involved, mostly during working activities,

included haulage/utility trucks (18 fires, 14 injuries, and 1

fatality), loaders (14 fires and 11 injuries), dozers (4 fires and

4 injuries), and dredges (3 fires and 3 injuries) (table 32 and

figure 14).

Table 27.–Number of mobile equipment fires for surface metal/nonmetal mines by ignition source,

equipment involved, and time period, 1990-1999

Equipment Ignition source

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No.

fires

No.

fires

No.

fires

No.

fires

No.

fires

No.

fires

Haulage/utility truck . . . . Hydraulic fluid/fuel on equipment hot surfaces . . . . . . . . . . 3 1 6 5 – 15

Heat source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – – – 1 – 1

Flame cutting/welding spark/slag . . . . . . . . . . . . . . . . . . . . – 1 – – 1 2

Flammable liquid/refueling fuel/fuel oil on hot surfaces . . . 1 1 – 1 1 4

Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 1 – – – 1

Scraper . . . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces .......... – 1 – – – 1

Excavator . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces .......... – 1 – – – 1

Shovel . . . . . . . . . . . . . . Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 – 1 1 – 3

Hydraulic fluid/fuel on equipment hot surfaces .......... 1 5 – 1 – 7

Overheated oil1 .................................. – 1 – – – 1

Flame cutting/weldingark/slag ...................... – 2 1 – – 3

Loader . . . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces .......... 2 2 – – – 4

Drill . . . . . . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces .......... – 1 2 1 – 4

Heat source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – – 1 – – 1

Dozer . . . . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces .......... 1 – – – – 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 17 11 10 2 49 1

Due to compressor malfunction.

Table 28.–Number of mobile equipment fires for surface metal/nonmetal mines by method of detection,

equipment involved, and time period, 1990-1999

Time period

Equipment Method of detection 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Haulage/utility truck . . . Visual-smoke ........ 3 1 1 2 – 7

Visual-sparks . . . . . . . . – 1 – – 1 2

Visual-flames/flash fire 1 1 3 5 1 11

Power loss . . . . . . . . . . – 1 2 – – 3

Scraper . . . . . . . . . . . . . Visual-flames/flash fire – 1 – – – 1

Excavator . . . . . . . . . . . Visual-flames/flash fire – 1 – – – 1

Shovel . . . . . . . . . . . . . Visual-smoke . . . . . . . . 1 1 – 1 – 3

Late detection-smoke . . 1 2 – – – 3

Visual-sparks . . . . . . . . – 2 1 – – 3

Visual-flames/flash fire – 2 – 1 – 3

Power trip . . . . . . . . . . . – – 1 – – 1

Undetected .......... – 1 – – – 1

Loader . . . . . . . . . . . . . Visual-flames/flash fire 2 2 – – – 4

Drill . . . . . . . . . . . . . . . . Late detection-smoke . . – – 1 – – 1

Visual-smoke . . . . . . . . – – 1 1 – 2

Visual-flames/flash fire – 1 1 – – 2

Dozer . . . . . . . . . . . . . . Visual-flames/flash fire 1 – – – – 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 17 11 10 2 49
27

Table 29.–Number of mobile equipment fires for surface metal/nonmetal mines by suppression method, 

equipment involved, and time period, 1990-1999

Time period

Equipment Suppression method 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Haulage/utility truck . . . FE-FSS-water-dry chemical powder1 .– – 1 – – 1

FE-water-foam-dry chemical powder2 1 1 – 1– 3

FE/manual3 ..................... – 1 1 1 1 4

Portable fire extinguisher .......... 3 2 – – 1 6

FE-water-foam-dry chemical powder2 – – 3 3– 6

Water . . . . . . . . . . . . . . . . . . . . . . . . . – – – 1 – 1

Destroyed/heavily damaged4 ....... – – – 1 – 1

FE-FSS-HD5 .................... – – 1 – – 1

Scraper . . . . . . . . . . . . . FE-water-foam-dry chemical powder2 – 1 – –– 1

Excavator . . . . . . . . . . . FE-dry chemical powder1 .......... – 1 – – – 1

Shovel . . . . . . . . . . . . . FE-FSS-dry chemical powder1 ...... – 1 – – – 1

Destroyed/heavily damaged4 ....... 1 3 – – – 4

FE/manual3 ..................... – 1 1 1 – 3

Portable fire extinguisher .......... – – 1 – – 1

FE–water-foam-dry chemical powder2 1 1 – 1– 3

Portable fire extinguisher .......... – 2 – – – 2

Loader . . . . . . . . . . . . . FE-FSS-foam-dry chemical powder1 .1 – – – – 1

FE-water-foam-dry chemical powder2 1 2 – –– 3

Drill . . . . . . . . . . . . . . . . FE-water-foam-dry chemical powder2 – 1 2 1– 4

Destroyed/heavily damaged4 ....... – – 1 – – 1

Dozer . . . . . . . . . . . . . . FE-water-foam-dry chemical powder2 1 – – –– 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 17 11 10 2 49

HD Heavily damaged.

FE Portable fire extinguisher.

FSS Machine fire suppression system. 1

Method used by fire departments following, at times, available FSS discharge by operator. 2

Methods used by fire brigades (mostly foam) and fire departments (mostly dry chemical powder) following available FSS discharge

by operator. 3

Methods used by welders to extinguish clothing or oxyfuel fires. 4

Usually due to failed fire-fighting methods, late fire detection, undetected fires, or fire size (one FSS activation failure). 5

Usually due to failed fire suppression methods.

Table 30.–Number of fire injuries per number of mobile equipment fires causing injuries and total fires at surface metal/nonmetal 

mines by year, ignition source, equipment involved, and location, 1990-1999

Year

No. fires

causing

injuries

No.

total

fires

No. fire

injuries Ignition source Equipment Location

1990 . . 1 2 1 Fuel oil on hot surfaces . . . . . . . . . . . . . . . . . . . . . Truck . . . . . . . . . . Haulage area.

1 1 Hydraulic fluid/fuel on equipment hot surfaces . . . . Truck . . . . . . . . . . Haulage area.

1991 . . 3 7 4 Hydraulic fluid/fuel on equipment hot surfaces .... Loader-dozer . . . Loading/mining areas.

1 1 Hydraulic fluid/fuel on equipment hot surfaces . . . . Truck . . . . . . . . . . Haulage area.

1992 . . 1 8 1 Hydraulic fluid/fuel on equipment hot surfaces .... Loader ........ Loading area.

1 1 Flame cutting/welding spark/slag . . . . . . . . . . . . . . Shovel . . . . . . . . Flame cutting/welding areas.1

1993 . . 1 9 1 Flame cutting/welding spark/slag . . . . . . . . . . . . . . Truck . . . . . . . . . . Flame cutting/welding areas.1

2 2 Hydraulic fluid/fuel on equipment hot surfaces . . . . Scraper-loader . . Mining/loading areas.

1 1 Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . . . Truck . . . . . . . . . . Haulage area.

1 1 Refueling fuel on hot surfaces . . . . . . . . . . . . . . . . Truck . . . . . . . . . . Maintenance area.

1994 . . 1 8 1 Flame cutting/welding spark/slag . . . . . . . . . . . . . . Shovel . . . . . . . . Flame cutting/welding areas.1

1 1 Hydraulic fluid/fuel on equipment hot surfaces . . . . Truck . . . . . . . . . . Haulageway.

19952 . 1 3 1 Hydraulic fluid/fuel on equipment hot surfaces . . . . Truck . . . . . . . . . . Haulage area.

1 – 1 Fuel oil on collision . . . . . . . . . . . . . . . . . . . . . . . . . Truck . . . . . . . . . . Maintenance area.

1996 . . 2 6 2 Hydraulic fluid/fuel on equipment hot surfaces . . . . Truck . . . . . . . . . . Haulage area.

2 2 Refueling fuel on hot surfaces . . . . . . . . . . . . . . . . Truck . . . . . . . . . . Haulage area.

1997 . . – 4 – – – –

1998 . . – – – – –

1999 . . 1 2 1 Flame cutting/welding spark/slag . . . . . . . . . . . . . . Truck . . . . . . . . . . Flame cutting/welding areas.1

1 1 Flammable liquid on hot surfaces . . . . . . . . . . . . . . Truck . . . . . . . . . . Maintenance area.

Total . . 24 49 24

1

Includes working and maintenance areas.

2

During 1995, there was one fire fatality.
28

Figure 12.—Mobile equipment fires, injuries, risk rates, and employees' working hours by time period for each metal/nonmetal mining

category, 1990-1999.

Table 31.–Number of mobile equipment fires, injuries, and risk rates for surface sand and gravel

and stone mines by state, equipment involved, and employees’ working hours, 1990-1999

State1 Equipment1 No. fires1 No. injuries Ewhr,2

 106 hr Irr3

AZ. . . . . . . . . . . . . Truck . . . . . . . . . . . . . . . 3 3 3.6 0.165

CA . . . . . . . . . . Truck . . . . . . . . . . . . . . . 4 3

Loader ............. 1 1

Drill . . . . . . . . . . . . . . . . 1 – 95.7 0.0084

FL . . . . . . . . . . Loader . . . . . . . . . . . . . 1 1 35.5 0.0056

GA . . . . . . . . . Loader . . . . . . . . . . . . . 2 2 21.2 0.019

IL . . . . . . . . . . . Dozer . . . . . . . . . . . . . . 1 1

Scraper ............. 1 1

Loader . . . . . . . . . . . . . 1 1 42 0.014

IN . . . . . . . . . . Tanker . . . . . . . . . . . . . 1 –

Truck . . . . . . . . . . . . . . . 1 1

Dredge . . . . . . . . . . . . . 1 1 34.1 0.012

KY . . . . . . . . . . Dozer . . . . . . . . . . . . . . 1 1 15.5 0.013

LA . . . . . . . . . . Dredge . . . . . . . . . . . . . 1 1 14.2 0.014

MI . . . . . . . . . . Truck . . . . . . . . . . . . . . . 3 2

Loader ............. 1 –

Shovel . . . . . . . . . . . . . 1 – 40 0.005

MS . . . . . . . . . Dredge . . . . . . . . . . . . . 1 1 15 0.013

NC . . . . . . . . . Crane . . . . . . . . . . . . . . 1 1 24 0.008

NE . . . . . . . . . . Truck . . . . . . . . . . . . . . . 1 1 1.5 0.13

NH . . . . . . . . . Loader . . . . . . . . . . . . . 2 2 6.4 0.03

NJ . . . . . . . . . . Truck . . . . . . . . . . . . . . . 1 1 9.2 0.022

NY . . . . . . . . . . Loader ............. 1 –

Backhoe-forklift-truck . . 1 – 41 –

OK . . . . . . . . . Loader . . . . . . . . . . . . . 1 1 17.5 0.011

OR . . . . . . . . . Dozer . . . . . . . . . . . . . . 1 1 13 0.015

PA . . . . . . . . . . Loader ............. 3 3

Truck . . . . . . . . . . . . . . . 2 1

Bucket . . . . . . . . . . . . . 1 1 58.3 0.017

PR . . . . . . . . . . Dozer . . . . . . . . . . . . . . 1 1 11.4 0.013

SC . . . . . . . . . . Loader ............. 1 –

Truck . . . . . . . . . . . . . . . 1 1 13 0.015

TN4 . . . . . . . . . Truck . . . . . . . . . . . . . . . 1 – 18 –

WV . . . . . . . . . Truck . . . . . . . . . . . . . . . 1 1 5.2 0.04

All other states . . . . . . . . . . . . . . . . . . . . – – 565.81 –

Total . . . . . . . . . . . . . . . . . . . . . . . . 46 35 1,101 3

0.006 1

Derived from MSHA "Fire Accident Abstract" and "Fire Accident Report" publications. 2

Derived from MSHA "Injury Experience in Mining" publications. 3

Calculated according to MSHA formula reported in the "Methodologies" section. 4

Tennessee had one fire fatality.
29

Figure 13.—Mobile equipment fires and injuries for surface sand and gravel and stone mines by state, 1990-1999.

Figure 14.—Major variables for mobile equipment fires at surface sand and gravel and stone mines, 1990-1999. (FE = portable fire

extinguisher.)
30

Table 32.–Number of mobile equipment fires, injuries, fatalities, and risk rates for surface sand and gravel and stone mines

by time period, equipment involved, activity, and employees’ working hours, 1990-1999

Equipment Activity

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

Loader .............. Loading ........... 2 1 2 2 2 2 2 2 1 1 9 8

Flame cutting/welding – – – – 1 1 – – – – 1 1

Maintenance/idle . . . – – – – 2 1 1 1 1 – 4 2

Haulage/utilitytruck1 . . . . Maintenance/idle . . . 2 2 3 3 1 1 1 – 1 1 8 7

Haulage/utility ...... – – 3 1 1 – 4 4 1 1 9 6

Flame cutting/welding 1 1 – – – – – – – – 1 1

Drill . . . . . . . . . . . . . . . . . Drilling ........... – – 1 – – – – – – – 1 –

Dozer . . . . . . . . . . . . . . . Mining . . . . . . . . . . . . – – 2 2 1 1 1 1 – – 4 4

Dredge . . . . . . . . . . . . . . Dredging .......... – – 1 1 1 1 – – – – 2 2

Flame cutting/welding – – – – 1 1 – – – – 1 1

Scraper . . . . . . . . . . . . . . Mining . . . . . . . . . . . . – – – – 1 1 – – – – 1 1

Backhoe/forklift/truck . . . Idle .............. – – – – – – 1 – – – 1 –

Shovel/bucket . . . . . . . . . Flame cutting/welding – – – – – – 1 1 1 – 2 1

Tanker . . . . . . . . . . . . . . Transportation . . . . . – – – – – – – – 1 – 1 –

Crane . . . . . . . . . . . . . . . Flame cutting/welding – – 1 1 – – – – – – 1 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4 13 10 11 9 11 9 6 3 46 35

No. fatalities . . . . . . . . . . . . . . . . . . . . . . . – 1 – – – 1

Ewhr,2

 106 hr . . . . . . . . . . . . . . . . . . . . . . . 213 208 222 220 238 1,101

Irr3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.004 0.01 0.008 0.008 0.003 0.006 1

This equipment caused one fire fatality.

2

Derived from MSHA "Injury Experience in Mining" publications. 3

Calculated according to MSHA formula reported in this text "Methodologies" section.

Most of the fires were caused by pressurized hydraulic

fluid/fuel (25 fires or 54%) sprayed onto equipment hot surfaces,

followed by flammable liquid/refueling fuel/oil on hot surfaces,

flame cutting/welding spark/slag, electrical short/arcing,

mechanical friction/collision, and overheated oil (table 33 and

figure 14). Operators/miners/welders detected most of the fires

when they started as flames/flash fires or pressure and power loss,

smoke, sparks, or by hearing an explosion. Most of the hydraulic

fluid/fuel fires, although detected when they started, grew out of

control (requiring fire-fighting interventions at least four times)

because of the continuous flow of fluids from pumps and tanks

due to engine shutoff failure, lack of an emergency line drainage

system, difficulty in reaching available emergency systems at

ground level, or lack of effective and rapid local fire-fighting

response capabilities. Three fires were detected late (which made

fire-fighting efforts ineffective), and one was undetected and

burned itself out (table 34 and figure 14). At least twice the cab

was suddenly engulfed in flames, forcing the operator to exit the

cab under difficult conditions most likely due to the ignition of

flammable vapors and mists that formed and penetrated the cab

during the spraying of hydraulic fluids onto equipment hot

surfaces.

Fire departments fought the hydraulic fluid/fuel fires with dry

chemicals and water. Four pieces of equipment were destroyed

or heavily damaged (table 35 and figure 14).

Data during the five time periods, including the number of

fires, fire injuries and fire fatalities, risk rates, and employees'

working hours according to the equipment involved and activity,

are shown in table 32 and partly illustrated in figure 12. Other

variables such as ignition source and methods of detection and

suppression are shown in tables 33-35.

Equipment fires and fire injuries increased sharply during

1992-1993, then decreased during subsequent periods, especially 1998-1999, accompanied by a small increase in employees' working hours.

During 1990-1991, there were five fires and four injuries.

The equipment involved included haulage/utility trucks (three

fires and three injuries) and loaders (two fires and one injury)

mostly during maintenance and loading activities. The Ewhr

value was 213 × 106

 hr (Irr = 0.004). The most common ignition sources were hydraulic fluid/fuel sprayed onto equipment

hot surfaces and flammable liquid/refueling fuel/oil on hot

surfaces. The most frequent methods of detection were operators who saw flames/flash fires and miners who saw flames.

The most commonly used suppression methods were portable

fire extinguishers, water, and dry chemical powder.

During 1992-1993, there were 13 fires, 10 injuries, and

1 fatality. The equipment involved included haulage/utility

trucks (six fires, four injuries, and one fatality), dozers, and

loaders (two fires and two injuries for each), and dredges (one

fire and one injury) mostly during haulage, mining, loading, and

dredging activities. The Ewhr value was 208 × 106

 hr (Irr

= 0.01). The ignition sources were hydraulic fluid/fuel sprayed

onto equipment hot surfaces, followed by flame cutting/welding

spark/slag, flammable liquid/refueling fuel/oil on hot surfaces,

and overheated oil. The most frequent methods of detection

were operators who saw flames/flash fires or experienced power

or pressure loss and operators/miners/welders who saw smoke

or sparks. The most commonly used suppression methods were

water, dry chemical powder, and portable fire extinguishers.

During 1994-1995, there were 11 fires and 9 injuries. The

equipment involved included loaders (five fires and four
31

injuries), dredges (two fires and two injuries), haulage/utility

trucks (two fires and one injury), and scrapers and dozers (one

fire and injury for each) mostly during loading, haulage,

dredging, and mining activities. The Ewhr value was 222 × 106

hr (Irr = 0.008). The ignition sources were hydraulic fluid/fuel

sprayed onto equipment hot surfaces, followed by flame

cutting/welding spark/slag, flammable liquid/refueling fuel/oil

on hot surfaces, and electrical short/arcing. The most frequent

methods of detection were operators who saw flames/flash fires,

miners who saw smoke, and welders who saw sparks (one fire

was undetected). The most commonly used suppression methods were water, dry chemical powder, and portable fire extinguishers (one equipment fire was not extinguished).

During 1996-1997, there were 11 fires and 9 injuries. The

equipment involved included haulage/utility trucks (five fires

and four injuries), loaders (three fires and three injuries), a dozer

and shovel (one fire and injury for each), and a backhoe,

forklift, and truck (one fire and no injuries) mostly during

haulage, loading, mining, and maintenance activities. The Ewhr

was 220 × 106

 hr (Irr = 0.008). The most common ignition

sources were hydraulic fluid/fuel sprayed onto equipment hot

surfaces, followed by flammable liquid/refueling fuel/oil on hot

surfaces, electrical short/arcing, and flame cutting/welding

spark/slag. The most frequent methods of detection were

operators who saw flames/flash fires and miners/welders who

saw smoke or sparks (two fires were detected late). The most

commonly used suppression methods were water, dry chemical

powder, and portable fire extinguishers (two equipment fires

involving four pieces of equipment were not extinguished).

During 1998-1999, there were six fires and three injuries.

The equipment involved included haulage/utility trucks (two

fires and two injuries), loaders (two fires and one injury), and a

shovel and tanker (one fire and no injuries for each) mostly

during haulage, loading, mining, and transport activities. The

Ewhr was 238 × 106

 hr (Irr = 0.003). The most common ignition sources were hydraulic fluid/fuel sprayed onto equipment

hot surfaces, followed by flammable liquid/refueling fuel/oil on

hot surfaces, hazardous material explosion, and mechanical

friction/collision. The most frequent methods of detection were

operators/miners who saw flames/flash fires and miners who

heard an explosion. The most commonly used suppression

methods were water, dry chemical powder, and portable fire

extinguishers (one equipment fire was not extinguished).

Table 36 shows the number of fire injuries per number of

fires causing injuries and total fires by year, ignition source,

equipment involved, and location. The highest number of fire

injuries occurred in 1993 (six fire injuries and one fire fatality

caused by seven equipment fires). These involved loaders,

dozers, trucks, dredges, and a crane during hydraulic fluid/fuel,

refueling fuel, and flame cutting/welding fires. The fatality,

which occurred in Tennessee during a hydraulic fluid/fuel fire

involving a haulage truck, was caused by flames that suddenly

engulfed the cab [MSHA 1993f].

MOBILE EQUIPMENT FIRES AT METAL/NONMETAL

AND STONE MILLS

At metal/nonmetal and stone mills, there were a total of 23

equipment fires during 1990-1999; 16 of those fires caused

16 injuries (table 37 and figure 15). Two fires with one injury

occurred at a metal mill, 5 fires with 3 injuries occurred at

nonmetal mills, and 16 fires with 12 injuries occurred at stone

mills. Two fires with two injuries involved contractors. In all,

one piece of equipment (4%) involved in a fire had a machine

fire suppression system.

Table 33.–Number of mobile equipment fires for surface sand and gravel and stone mines by ignition source, 

equipment involved, and time period, 1990-1999

Time period

Equipment Ignition source 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Loader . . . . . . . . . . . . Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . . . . . . – ––1– 1

Hydraulic fluid/fuel on equipment hot surfaces ....... 2 2311 9

Flame cutting/welding spark/slag . . . . . . . . . . . . . . . . . – –1–– 1

Flammable liquid on hot surfaces . . . . . . . . . . . . . . . . . – –1–– 1

Mechanical friction/collision ..................... – ––11 2

Haulage/utility truck . . Flammable liquid/refueling fuel/fuel oil on hot surfaces . 2 1111 6

Hydraulic fluid/fuel on equipment hot surfaces ....... – 4131 9

Flame cutting/welding spark/slag . . . . . . . . . . . . . . . . . 1 1––– 2

Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . . . . . . – ––1– 1

Drill . . . . . . . . . . . . . . . Overheated oil1 ............................... – 1––– 1

Dozer . . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces ....... – 2–1– 3

Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . . . . . . – –1–– 1

Dredge . . . . . . . . . . . . Flame cutting/welding spark/slag . . . . . . . . . . . . . . . . . – –1–– 1

Hydraulic fluid/fuel on equipment hot surfaces ....... – 11–– 2

Scraper . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces ....... – –1–– 1

Backhoe/forklift/truck . Hydraulic fluid/fuel on equipment hot surfaces ....... – ––1– 1

Shovel/bucket . . . . . . . Flame cutting/welding spark/slag . . . . . . . . . . . . . . . . . – ––11 2

Tanker . . . . . . . . . . . . Hazardous material-explosion ................... – –––1 1

Crane . . . . . . . . . . . . . Flame cutting/welding spark/slag . . . . . . . . . . . . . . . . . – 1––– 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 13 11 11 6 46 1

Due to compressor malfunction.
32

Table 34.–Number of mobile equipment fires for surface sand and gravel and stone mines by method of detection,

 equipment involved, and time period, 1990-1999

Equipment Method of detection

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Loader . . . . . . . . . . . . . Visual-flames/flash fire . . . 2 2 3 1 2 10

Visual-sparks . . . . . . . . . . – – 1 – – 1

Visual-smoke . . . . . . . . . . – – – 2 – 2

Undetected ............ – – 1 – – 1

Haulage/utility truck . . . Visual-flames/flash fire . . . 2 2 2 2 2 10

Power loss . . . . . . . . . . . . – 1 – – – 1

Visual-smoke . . . . . . . . . . – 1 – 2 – 3

Visual-sparks . . . . . . . . . . 1 1 – – – 2

Late detection-smoke . . . . – 1 – 1 – 2

Drill . . . . . . . . . . . . . . . . Pressure loss . . . . . . . . . . – 1 – – – 1

Dozer . . . . . . . . . . . . . . Visual-flames/flash fire . . . – 2 – 1 – 3

Visual-smoke . . . . . . . . . . – – 1 – – 1

Dredge . . . . . . . . . . . . . Visual-flames/flash fire . . . – 1 1 – – 2

Visual-sparks . . . . . . . . . . – – 1 – – 1

Scraper . . . . . . . . . . . . . Visual-flames/flash fire . . . – – 1 – – 1

Backhoe-forklift-truck . . Late detection-smoke .... – – – 1 – 1

Shovel-bucket . . . . . . . . Visual-sparks . . . . . . . . . . – – – 1 1 2

Tanker . . . . . . . . . . . . . Explosion . . . . . . . . . . . . . – – – – 1 1

Crane . . . . . . . . . . . . . . Visual-sparks . . . . . . . . . . – 1 – – – 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 13 11 11 6 46

Table 35.–Number of mobile equipment fires for surface sand and gravel and stone mines by suppression method, 

equipment involved, and time period, 1990-1999

Equipment Suppression method

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Loader . . . . . . . . . . . . . Portable fire extinguisher ......... 1 – – 2– 3

FE-water-dry chemical powder1 .... 1 2 2 12 8

FE/manual2 .................... – – 2 –– 2

Destroyed/heavily damaged3 ...... – – 1 –– 1

Haulage/utility truck . . . Dry chemical powder-water1 ....... – 3 – 21 6

Portable fire extinguisher ......... 2 2 – 21 7

FE/manual2 .................... 1 – 1 –– 2

Water-dry chemical powder1 ...... – 1 1 –– 2

Destroyed/heavily damaged3 ...... – – – 1– 1

Drill . . . . . . . . . . . . . . . . FE-dry chemical powder-water1 .... – 1 – –– 1

Dozer . . . . . . . . . . . . . . Dry chemical powder-water1 ....... – 2 – 1– 3

Portable fire extinguisher ......... – – 1 –– 1

Dredge . . . . . . . . . . . . . FE-dry chemical powder-water1 .... – 1 1 –– 2

FE/manual2 .................... – – 1 –– 1

Scraper . . . . . . . . . . . . . FE-dry chemical powder/water1 .... – – 1 –– 1

Backhoe/forklift/truck4 . . Destroyed/heavily damaged3 ...... – – – 1– 1

Shovel/bucket . . . . . . . . FE/manual2 .................... – – – 11 2

Tanker . . . . . . . . . . . . . Destroyed/heavily damaged3 ...... – – – –1 1

Crane . . . . . . . . . . . . . . Portable fire extinguisher ......... – 1 – –– 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 13 11 11 6 46

FE Portable fire extinguisher.

1

Methods used by fire departments.

2

Methods used by welders to extinguish clothing or oxyfuel fires. 3

Usually due to undetected fires or fire size.

4

Three pieces of equipment were destroyed during one fire.

The highest number of equipment fires and fire injuries

occurred in Missouri (seven fires and four injuries), followed by

Pennsylvania and Michigan (two fires and two injuries for each

state). Michigan had the highest injury risk rate (Irr = 0.024).

For metal/nonmetal and stone mills, the total Ewhr value was

1,219 × 106

 hr (Irr = 0.003) (table 37).

The equipment involved, mostly during working and

maintenance activities, included loaders (eight fires and six

injuries), haulage/utility trucks (seven fires and five injuries),

shovels (three fires and one injury), and dozers (two fires and

one injury) (table 38 and figure 16).

Most of the fires were caused by pressurized hydraulic

fluid/fuel (seven fires or 30%) sprayed onto equipment hot

surfaces, followed by flame cutting/welding spark/slag and

flammable liquids on hot surfaces/collision. Other sources were

overheated oil and transmission oil on hot surfaces, electrical

short/arcing, and hot material (table 39 and figure 16).
33

Figure 15.—Mobile equipment fires and injuries for metal/nonmetal and stone mills by state, 1990-1999.

Figure 16.—Major variables for mobile equipment fires at metal/nonmetal and stone mills, 1990-1999. (FE = portable fire extinguisher;

FSS = machine fire suppression system.)
34

Table 36.–Number of fire injuries per number of mobile equipment fires causing injuries and total fires at surface

sand and gravel and stone mines by year, ignition source, equipment involved, and location, 1990-1999

Year

No. fires

causing

injuries

No.

total

fires

No.

fire

injuries

Ignition source Equipment Location

1990 . . . 2 4 2 Refueling fuel on hot surfaces . . . . . . . . . . . . . . . Truck . . . . . . . . . . . Maintenance areas.

1 – 1 Flame cutting/welding spark/slag . . . . . . . . . . . . . Truck . . . . . . . . . . . Flame cutting/welding areas.1

1991 . . . 1 1 1 Hydraulic fluid on equipment hot surfaces ...... Loader ......... Loading area.

1992 . . . 3 6 3 Hydraulic fluid/fuel on equipment hot surfaces . . . Truck-dozer . . . . . Haulage/maintenance areas.

1 – 1 Flame cutting/welding spark/slag . . . . . . . . . . . . . Truck . . . . . . . . . . . Flame cutting/welding areas.1

19932 . . 5 7 4 Hydraulic fluid/fuel on equipment hot surfaces . . . Loader-dredge-

 dozer-truck.

Haulage/mining areas.

1 – 1 Refueling fuel on hot surfaces . . . . . . . . . . . . . . . Truck . . . . . . . . . . . Haulage area.

1 – 1 Flame cutting/welding spark/slag . . . . . . . . . . . . . Crane . . . . . . . . . . Flame cutting/welding areas.1

1994 . . . 2 4 2 Hydraulic fluid/fuel on equipment hot surfaces . . . Loader-dredge . . . Loading/dredging areas.

1 – 1 Flame cutting/welding spark/slag . . . . . . . . . . . . . Loader . . . . . . . . . Flame cutting/welding areas.1

1995 . . . 2 7 2 Hydraulic fluid/fuel on equipment hot surfaces . . . Loader-scraper . . . Loading/mining areas.

2 – 2 Flammable liquid/refueling fuel on hot surfaces . . Loader-truck ..... Loading/haulage areas.

1 – 1 Flame cutting/welding spark/slag . . . . . . . . . . . . . Dredge . . . . . . . . . Dredging area.

1 – 1 Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . . Dozer . . . . . . . . . . Mining area.

1996 . . . 4 9 4 Hydraulic fluid/fuel on equipment hot surfaces . . . Loader-truck-dozer Loading/mining/haulage areas.

2 – 2 Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . . Truck-loader . . . . . Haulage/loading areas.

1 – 1 Fuel oil on hot surfaces . . . . . . . . . . . . . . . . . . . . Truck . . . . . . . . . . . Haulage area.

1997 . . . 1 2 1 Mechanical friction ........................ Loader ......... Loading area.

1 – 1 Flame cutting/welding spark/slag . . . . . . . . . . . . . Bucket . . . . . . . . . Flame cutting/welding areas.1

1998 . . . 2 4 2 Hydraulic fluid/fuel on equipment hot surfaces . . . Truck-loader . . . . . Haulage-loading areas.

1 – 1 Flammable liquid on hot surfaces . . . . . . . . . . . . . Truck . . . . . . . . . . . Haulage area.

1999 . . . – 2 – – – –

Total . . . 36 46 35

1

Includes working and maintenance areas.

2

During 1993, there was one fire fatality.

Table 37.–Number of mobile equipment fires, injuries, and risk rates for metal/nonmetal and

stone mills by state, equipment involved, and employees’ working hours, 1990-1999

State1 Equipment1 No. fires1 No. injuries1 Ewhr,2

 106 hr Irr3

AZ . . . . . . . . . . . . . . Shovel . . . . . . . . . 2 – 66.5 –

GA . . . . . . . . . . . . . Forklift . . . . . . . . . . 1 1 85.2 0.0024

IL . . . . . . . . . . . . . . . Loader . . . . . . . . . 1 – 30 –

Locomotive . . . . . . 1 1 – 0.0067

LA . . . . . . . . . . . . . . Loader . . . . . . . . . 1 1 1 0.2

MI . . . . . . . . . . . . . . Drill . . . . . . . . . . . . 1 1

Truck . . . . . . . . . . . 1 1 17 0.024

MO . . . . . . . . . . . . . Dozer . . . . . . . . . . 1 –

Loader ......... 3 2

Truck . . . . . . . . . . . 3 2 41.3 0.02

NJ . . . . . . . . . . . . . . Shovel . . . . . . . . . 1 1 0.6 0.33

NY . . . . . . . . . . . . . . Loader . . . . . . . . . 1 1 1.1 0.2

OH . . . . . . . . . . . . . Truck . . . . . . . . . . . 1 –

Loader . . . . . . . . . 1 1 29 0.007

OR . . . . . . . . . . . . . Dozer . . . . . . . . . . 1 1 0.24 0.83

PA . . . . . . . . . . . . . . Truck . . . . . . . . . . . 2 2 53.1 0.0075

SC . . . . . . . . . . . . . . Loader . . . . . . . . . 1 1 12 0.017

All other states . . . . . . . . . . . . . . . . . . . . – – 882 –

Total . . . . . . . . . . . . . . . . . . . . 23 16 1,219 3

0.003 1

Derived from MSHA "Fire Accident Abstract" and "Fire Accident Report" publications. 2

Derived from MSHA "Injury Experience in Mining" publications. 3

Calculated according to MSHA formula reported in the "Methodologies" section.
35

Table 38.–Number of mobile equipment fires, injuries, and risk rates for metal/nonmetal and stone mills by time period, 

equipment involved, activity, and employees’ working hours, 1990-1999

Equipment Activity

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No.

fires

No. 

injuries

No.

fires

No. 

injuries

No.

fires

No. 

injuries

No.

fires

No. 

injuries

No.

fires

No. 

injuries

No.

fires

No. 

injuries

Loader .......... Loading ............ 2 2 – – 1 1 1 1 – – 4 3

Flame cutting/welding – – 1 1 – – – – 1 1 2 2

Maintenance/idle .... – – – – – – 2 – – – 2 1

Haulage/utility truck Haulage/utility ....... 2 2 1 – 1 1 1 1 – – 5 4

Maintenance ........ – – 1 1 1 – – – – – 2 1

Dozer . . . . . . . . . . . Maintenance/idle .... – – 1 1 – – – – 1 – 2 1

Shovel . . . . . . . . . . Flame cutting/welding – – – – – – 1 1 1 – 2 1

Maintenance/idle .... – – 1 – – – – – – – 1 –

Locomotive . . . . . . . Transportation . . . . . . 1 1 – – – – – – – – 1 1

Drill . . . . . . . . . . . . . Flame cutting/welding 1 1 – – – – – – – – 1 1

Forklift . . . . . . . . . . . Maintenance ........ – – 1 1 – – – – – – 1 1

Total . . . . . . . . . . . . . . . . . . . . . . . . 6 6 6 4 3 2 5 3 3 1 23 16

Ewhr,1

 106 hr . . . . . . . . . . . . . . . . . . 259 247 248 236 229 1,219

Irr1 . . . . . . . . . . . . . . . . . . . . . . . . . . 0.005 0.003 0.002 0.003 0.001 2

0.003 1

Derived from MSHA "Injury Experience in Mining" publications. 2

Calculated according to MSHA formula reported in the "Methodologies" section.

Table 39.–Number of mobile equipment fires for metal/nonmetal and stone mills by ignition source,

equipment involved, and time period, 1990-1999

Time period

Equipment Ignition source 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Loader . . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces 1 – – 1 – 2

Flame cutting/welding spark/slag . . . . . . . . . . – 1 – – 1 2

Hot material/fuel . . . . . . . . . . . . . . . . . . . . . . . – – 1 1 – 2

Overheated oil1 ........................ – – – 1 – 1

Flammable liquid on collision ............. 1 – – – – 1

Haulage/utility truck . . . Hydraulic fluid/fuel on equipment hot surfaces 2 1 1 1 – 5

Flammable liquid on hot surfaces . . . . . . . . . . – 1 – – – 1

Overheated oil1 ........................ – – 1 – – 1

Dozer . . . . . . . . . . . . . . Electrical short/arcing . . . . . . . . . . . . . . . . . . . – – – – 1 1

Transmission oil-hot surfaces . . . . . . . . . . . . . – 1 – – – 1

Shovel . . . . . . . . . . . . . Flame cutting/welding spark/slag . . . . . . . . . . – – – 1 1 2

Flammable liquid on hot surfaces . . . . . . . . . . – 1 – – – 1

Drill . . . . . . . . . . . . . . . . Flame cutting/welding spark/slag . . . . . . . . . . 1 – – – – 1

Locomotive . . . . . . . . . . Electrical short/arcing . . . . . . . . . . . . . . . . . . . 1 – – – – 1

Forklift . . . . . . . . . . . . . . Flammable liquid on hot surfaces . . . . . . . . . . – 1 ––– 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 6 3 5 3 23 1

Due to compressor malfunction.

One fuel fire involving a truck with a machine fire

suppression system continued to burn until it was extinguished

by firefighters because of engine shutoff failure upon activation

of the fire suppression system.

Operators/miners/welders detected most of the fires when they

started as flames/flash fires, smoke, or sparks. One fire was detected late (which made fire-fighting efforts ineffective), and two

fires were undetected (burned themselves out) (table 40 and

figure 16). Most of the hydraulic fluid/fuel fires, although detected by the operators when they started, grew out of control

(requiring fire-fighting interventions at least twice) because of the

continuous flow of fluids from pumps and tanks due to engine

shutoff failure, lack of an emergency line drainage system, difficulty in reaching available emergency systems at ground level,

or lack of effective and rapid local fire-fighting response capabilities. On at least one occasion the cab was suddenly engulfed

in flames, forcing the operator to exit under difficult conditions

most likely due to the ignition of flammable vapors and mists that

formed and penetrated the cab during the spraying of hydraulic

fluids onto equipment hot surfaces.

Fire brigades and fire departments fought the hydraulic fluid/

fuel fires with foam, dry chemical powder, and water (table 41

and figure 16).

Data during the five time periods, including the number of

fires and injuries, risk rates, and employees' working hours according to the equipment involved and activity, are shown in

table 38 and partly illustrated in figure 12. Other variables such

as ignition source and methods of detection and suppression are

shown in tables 39-41.

Equipment fires decreased sharply during 1994-1995,

followed by small increases and decreases during subsequent

periods. This was accompanied by a small decline in
36

employees' working hours. Fire injuries decreased steadily

during most of the periods.

During 1990-1991, there were six fires and six injuries. The

equipment involved included haulage/utility trucks and loaders

(two fires and two injuries for each) and a drill and locomotive

(one fire and one injury for each) during haulage, loading, transportation, and flame cutting/welding activities. The Ewhr value

was 259 × 106

 hr (Irr = 0.005). The ignition sources were hydraulic fluid/fuel sprayed onto equipment hot surfaces, followed

by electrical short/arcing, flammable liquids on hot surfaces, and

flame cutting/welding spark/slag. The most frequent methods

of detection were operators who saw flames/flash fires or

sparks. The most commonly used suppression methods were

foam, dry chemical powder, water, and portable fire

extinguishers. A machine fire suppression system was

discharged once.

During 1992-1993, there were six fires and four injuries. The

equipment involved included haulage/utility trucks (two fires

and one injury) and a loader, dozer, and forklift (one fire and

one injury for each) mostly during mining and maintenance

activities. The Ewhr value was 247 × 106

 hr (Irr = 0.003). The

most common ignition sources were flammable liquids on hot

surfaces followed by hydraulic fluid/fuel sprayed onto

equipment hot surfaces. The most frequent methods of

detection were operators/miners who saw flames or smoke. The

most commonly used suppression methods were portable fire

extinguishers, foam, dry chemical powder, and water.

During 1994-1995, there were three fires and two injuries.

The equipment involved included haulage/utility trucks (two

fires and one injury) and a loader (one fire and one injury)

during haulage, loading, and maintenance activities. The Ewhr

value was 248 × 106

 hr (Irr = 0.002). The ignition sources were

hot material/fuel, overheated oil, and hydraulic fluid/fuel

sprayed onto equipment hot surfaces. The methods of detection

were miners who saw smoke and operators who saw flames/

flash fires (one fire was undetected). The suppression methods

used were foam, dry chemical powder, and portable fire

extinguishers and water alone.

During 1996-1997, there were five fires and three injuries.

The equipment involved included loaders (three fires and one

injury) and a haulage truck and shovel (one fire and one injury

for each) mostly during loading, haulage, and maintenance

activities. The Ewhr value was 236 × 106

 hr (Irr = 0.003). The

ignition sources were hydraulic fluid/fuel sprayed onto equipment hot surfaces, flame cutting/welding spark/slag, overheated

oil, and hot material/fuel. The most frequent methods of detection were operators who saw flames/flash fires and operators/

miners who saw smoke (one fire was detected late). The most

commonly used suppression methods were foam, dry chemical

powder, water, and portable fire extinguishers.

During 1998-1999, there were three fires and one injury. The

equipment involved included a loader (one fire and one injury)

and a dozer and shovel (one fire and no injuries for each) mostly

during flame cutting/welding and maintenance activities. The

Ewhr value was 229 × 106

 hr (Irr = 0.001). The ignition sources

were flame cutting/welding spark/slag followed by electrical

short/arcing. The methods of detection were welders/miners

who saw sparks (one fire was undetected). The suppression

methods used were manual methods and portable fire extinguishers (one equipment fire was not extinguished).

Table 42 shows the number of fire injuries per number of

fires causing injuries and total fires by year, ignition source,

equipment involved, and location. The highest number of fire

injuries was recorded in 1990 (four fire injuries caused by four

equipment fires). These involved trucks, loaders, and drills

during hydraulic fluid/fuel, flammable liquid, and flame cutting/

welding fires.

MOBILE EQUIPMENT FIRES IN UNDERGROUND

METAL/NONMETAL AND STONE MINES

At underground metal/nonmetal and stone mines, there were

a total of 24 equipment fires during 1990-1999; 7 injuries were

caused by 4 of those fires (table 43 and figure 17). Ten fires

with one injury occurred at metal mines; nine fires with six

injuries occurred at nonmetal mines; and five fires with no

injuries occurred at stone mines. One fire with no injuries

involved a contractor. In all, four pieces of equipment (17%)

involved in the fires had machine fire suppression systems.

The highest number of fires occurred in New York and Idaho

(four fires and no injuries for each state), followed by Louisiana

(three fires and two injuries) and Michigan (two fires and five

injuries). Michigan had the highest injury risk rate (Irr = 0.122).

For underground metal/nonmetal and stone mines, the total

Ewhr value was 214 × 106

 hr (Irr = 0.007) (table 43).

The equipment involved, mostly during working activities,

included scoops (five fires and five injuries), locomotives (three

fires and no injuries), haulage/utility trucks (five fires and no

injuries), loaders (three fires and no injuries), and power scalers

(two fires and no injury) (table 44 and figure 18).

Most of the fires were caused by pressurized hydraulic fluid

(12 fires or 50%) sprayed onto equipment hot surfaces followed

by electrical short/arcing and flammable liquid/motor/fuel oil on

hot surfaces. Other sources were flame cutting/welding spark/

slag and overheated oil on hot surfaces (table 45 and figure 18).

Operators/miners detected most of the fires when they started

as flames/flash fires, smoke, or power loss; one was undetected and

burned itself out (table 46 and figure 18). Most of the hydraulic

fluid fires grew out of control (requiring at least 10 mine rescue

interventions) because of the continuous flow of fluids from pumps

and tanks due to engine shutoff failure, lack of an emergency line

drainage system, or lack of effective and rapid local fire-fighting

response capabilities. At least twice the cab was suddenly engulfed

in flames, forcing the operator to exit the cab under difficult

conditions most likely due to the ignition of flammable vapors and

mists that formed and penetrated the cab. Upon mine/section

evacuation, mine rescue teams fought the electrical and hydraulic

fluid fires with dry chemical powder, rock dust, and water. Four

pieces of equipment were destroyed or heavily damaged because

of failed fire suppression methods, late machine fire suppression

system discharge, or undetected fires (table 47 and figure 18).
37

Figure 17.—Mobile equipment fires and injuries for underground metal/nonmetal and stone mines by state, 1990-1999.

Figure 18.—Major variables for mobile equipment fires in underground metal/nonmetal and stone mines, 1990-1999. (FE = portable

fire extinguisher; FSS = machine fire suppression system.)

The four hydraulic fluid fires involving equipment with

machine fire suppression systems behaved as follows. In the

first instance, the fire, which involved a scoop, burned out of

control because the system failed to activate promptly. In the

second and third instances, the fires, which involved a scoop

and power scaler, raged out of control because the operators

failed to activate the fire suppression systems. In the last case,

the fire, which involved a loader, was contained by cab dual

activation of the fire suppression and engine shutoff systems.

Data during the five time periods, including the number of

fires and fire injuries, risk rates, and employees' working hours

according to the equipment involved and activity, are shown in

table 44 and partly illustrated in figure 12. Other variables such

as ignition source and methods of detection and suppression are

shown in tables 45-47.

Equipment fires and fire injuries increased sharply during

1996-1997, then decreased sharply during 1998-1999,

accompanied by small changes in employees' working hours.
38

Table 40.–Number of mobile equipment fires for metal/nonmetal and stone mills by method of detection, 

equipment involved, and time period, 1990-1999

Time period

Equipment Method of detection 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Loader . . . . . . . . . . . . . Visual-flames/flash fire . . . . . 2 – – 1 – 3

Visual-sparks . . . . . . . . . . . . – 1 – – 1 2

Visual-smoke . . . . . . . . . . . . – – 1 1 – 2

Late detection-smoke . . . . . . – – – 1 – 1

Haulage/utility truck . . . Visual-flames/flash fire ..... 2 1 1 1 – 5

Visual-smoke . . . . . . . . . . . . – 1 – – – 1

Undetected .............. – – 1 – – 1

Dozer . . . . . . . . . . . . . . Visual-smoke . . . . . . . . . . . . – 1 – – – 1

Undetected .............. – – – – 1 1

Shovel . . . . . . . . . . . . . Visual-sparks . . . . . . . . . . . . – – – 1 1 2

Visual-flash fire/flash fire . . . – 1 – – – 1

Drill . . . . . . . . . . . . . . . . Visual-sparks . . . . . . . . . . . . 1 – – – – 1

Locomotive . . . . . . . . . . Visual-sparks . . . . . . . . . . . . 1 – – – – 1

Forklift . . . . . . . . . . . . . . Visual-flames/flash fire . . . . . – 1 – – – 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 6 3 5 3 23

Table 41.–Number of mobile equipment fires for metal/nonmetal and stone mills by suppression method,

equipment involved, and time period, 1990-1999

Time period

Equipment Suppression method 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Loader . . . . . . . . . . . . . Portable fire extinguisher ............ 1 – – 1 1 3

FE-water-foam-dry chemical powder1 .. 1 – – 2 – 3

FE/manual2 ....................... – 1 – – – 1

Water . . . . . . . . . . . . . . . . . . . . . . . . . . . – – 1 – – 1

Haulage/utility truck . . . Portable fire extinguisher ............ 1 1 1 – – 3

FE-water-foam-dry chemical powder1 .. – 1 1 1 – 3

FSS-water-foam-dry chemical powder3 1 – – –– 1

Dozer . . . . . . . . . . . . . . Portable fire extinguisher ............ – 1 – – – 1

Destroyed/heavily damaged4 ......... – – – – 1 1

Shovel . . . . . . . . . . . . . FE/manual2 ....................... – – – 1 1 2

Portable fire extinguisher ............ – 1 – – – 1

Drill . . . . . . . . . . . . . . . . FE/manual2 ....................... 1 – – – – 1

Locomotive . . . . . . . . . . Portable fire extinguisher ............ 1 – – – – 1

Forklift . . . . . . . . . . . . . . Portable fire extinguisher ............ – 1 – – – 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 6 3 5 3 23

FSS Machine fire suppression system.

FE Portable fire extinguisher.

1

Methods used by fire brigades (mostly foam) and fire departments (mostly dry chemical powder). 2

Methods used by welders to extinguish clothing or oxyfuel fires. 3

Methods used by fire brigades and fire departments following available FSS discharge by operator. 4

Usually due to undetected fires.

Table 42.–Number of fire injuries per number of mobile equipment fires causing injuries and total fires at metal/nonmetal and stone

mills by year, ignition source, equipment involved, and location, 1990-1999

Year No. total

fires

No. fires

causing

injuries

No. fire

injuries Ignition source Equipment Location

1990 . . . 4 2 2 Hydraulic fluid/fuel on equipment hot surfaces . Truck . . . . . . Haulage area.

– 1 1 Flammable liquid-collision ................ Loader . . . . Gas pump area.

– 1 1 Flame cutting/welding spark/slag . . . . . . . . . . . Drill . . . . . . . Flame cutting/ welding areas.1

1991 . . . 2 1 1 Hydraulic fluid/fuel on equipment hot surfaces . Loader .... Loading area.

– 1 1 Electrical short/arcing . . . . . . . . . . . . . . . . . . . . Locomotive Transport area.

1992 . . . 4 1 1 Transmission oil on hot surfaces . . . . . . . . . . . Dozer . . . . . Mining area.

– 1 1 Flame cutting/welding spark/slag . . . . . . . . . . . Loader . . . . Flame cutting/welding areas.1

1993 . . . 2 2 2 Flammable liquid on hot surfaces . . . . . . . . . . . Forklift-truck Maintenance area.

1994 . . . 1 1 1 Hydraulic fluid/fuel on equipment hot surfaces . Truck . . . . . . Haulage area.

1995 . . . 2 1 1 Hot material ........................... Loader . . . . Kiln area.

1996 . . . 2 2 2 Hydraulic fluid/fuel on equipment hot surfaces . Loader/truck Loading/haulage areas.

1997 . . . 3 1 1 Flame cutting/welding spark/slag . . . . . . . . . . . Shovel . . . . Flame cutting/welding areas.1

1998 . . . – – – – – –

1999 . . . 3 1 1 Flame cutting/welding spark/slag ........... Loader .... Loading area.

Total . . . 23 16 16

1

Includes working and maintenance areas.
39

Table 43.–Number of mobile equipment fires, injuries, and risk rates for

underground metal/nonmetal and stone mines by state, equipment 

involved, and employees’ working hours, 1990-1999

State1 Equipment1 No. fires1 No. injuries1 Ewhr,2

 106 hr Irr3

AZ . . . . . Trolley . . . . . . . 1 – 28.1 –

ID . . . . . Locomotive . . . 3 –

Loader . . . . . . 1 – 9.2 –

IL . . . . . . Truck . . . . . . . . 1 – 2 –

IN . . . . . Scaler . . . . . . . 1 – 1.4 –

KY . . . . . Crane . . . . . . . 1 – 8.1 –

LA . . . . . Drill . . . . . . . . . 1 1

Scoop . . . . . . . 1 1

Loader . . . . . . 1 – 7 0.057

MI . . . . . Scoop . . . . . . . 1 4

Ore cart . . . . . . 1 1 8.2 0.122

MO . . . . Truck . . . . . . . . 2 – 4.6 –

NM . . . . Shuttle car . . . 1 – 17.2 –

NV . . . . . Scoop . . . . . . . 1 – 12 –

NY . . . . . Scoop . . . . . . . 2 –

Scaler . . . . . . . 1 – 7.5 –

Bucket . . . . . . 1 –

OH . . . . Truck . . . . . . . . 1 – 5.3 –

SD . . . . . Truck . . . . . . . . 1 – 13 –

TN . . . . . Loader . . . . . . 1 – 13 –

All other states . . . . . . . . . . – – 77.4 –

Total . . . . . . . . . . . . . . . 24 7 214 3

0.007 1

Derived from MSHA "Fire Accident Abstract" and "Fire Accident Report" publications. 2

Derived from MSHA "Injury Experience in Mining" publications. 3

Calculated according to MSHA formula reported in the "Methodologies" section.

Table 44.–Number of mobile equipment fires, injuries, and risk rates for underground metal/nonmetal and stone mines 

by time period, equipment involved, activity, and employees’ working hours, 1990-1999

Equipment Activity

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No.

fires

No.

injuries

No.

fires

No.

injuries

No.

fires

No.

injuries

No. 

fires

No.

injuries

No.

fires 

No.

injuries

No.

fires 

No.

injuries

Power scaler . . . . . . . . . Idle . . . . . . . . . . . . . . – – – – – – – – 1 – 1 –

Mining . . . . . . . . . . . . – – – – 1 – – – – – 1 –

Loader . . . . . . . . . . . . . Mucking . . . . . . . . . . – – – – 1 – 1 – – – 2 –

Loading ........... – – – – – – 1 – – – 1 –

Scoop . . . . . . . . . . . . . . Mining . . . . . . . . . . . . – – 1 1 – – 3 4 – – 4 5

Mucking . . . . . . . . . . – – – – – – – – 1 – 1 –

Drill . . . . . . . . . . . . . . . . Drilling ........... – – – – – – 1 1 – – 1 1

Haulage/utility truck . . . Haulage .......... – – 1 – – – 1 – – – 2 –

Utility ............. – – 2 – – – 1 – – – 3 –

Shuttle car . . . . . . . . . . Transportation . . . . . – – 1 – – – – – – – 1 –

Ore cart . . . . . . . . . . . . . Transportation . . . . . 1 1 – – – – – – – – 1 1

Locomotive . . . . . . . . . . Transportation . . . . . – – – – – – 1 – – – 1 –

Maintenance ....... 1 – – – – – – – – – 1 –

Idle . . . . . . . . . . . . . . – – – – – – – – 1 – 1 –

Trolley . . . . . . . . . . . . . . Transportation . . . . . – – – – 1 – – – – – 1 –

Crane . . . . . . . . . . . . . . Idle . . . . . . . . . . . . . . 1 – – – – – – – – – 1 –

Slusher bucket . . . . . . . Flame cutting/welding – – – – 1 – – – – – 1 –

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1 5 1 4 – 9 5 3 – 24 7

Ewhr,1

 106 hr . . . . . . . . . . . . . . . . . . . . . . . . . 48 41 41 44 40 214

Irr2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.004 0.005 – 0.027 – 2

0.007 1

Derived from MSHA "Injury Experience in Mining" publications. 2

Calculated according to MSHA formula reported in the "Methodologies" section.

Data during the five time periods show large increases in the

number of equipment fires during 1992-1993 and 1996-1997

and an increase in injuries during 1996-1997 only, accompanied

by a small decline in working hours throughout all of the

periods.

During 1990-1991, there were three fires and one injury. The

equipment involved included an ore cart (one fire and one

injury) and a locomotive and crane (one fire and no injuries for

each) during transportation and maintenance activities. The

Ewhr value was 48 × 106

 hr (Irr = 0.004). The ignition sources
40

were hydraulic fluid sprayed onto equipment hot surfaces,

followed by electrical short/arcing. The methods of detection

were operators who saw flames/flash fires and miners who saw

smoke (one fire was undetected). The suppression methods

were rock dust, water, and portable fire extinguishers (one

equipment fire was not extinguished).

During 1992-1993, there were five fires and one injury. The

equipment involved included haulage/utility trucks (three fires and

no injuries), a scoop (one fire and one injury), and a shuttle car

(one fire and no injuries) during haulage/utility, mining, and

transport activities. The Ewhr value was 41 × 106

 hr (Irr = 0.005).

The ignition sources were hydraulic fluid sprayed onto equipment

hot surfaces, followed by electrical short/arcing and motor oil on

hot surfaces. The most frequent methods of detection were

operators who saw flames/flash fires or experienced power loss

and miners who saw smoke. The most commonly used suppression methods were dry chemical powder, rock dust, and water

(one equipment fire was not extinguished). A machine fire

suppression system was not activated.

During 1994-1995, there were four fires and no injuries. The

equipment involved included a loader, power scaler, slusher/

bucket, and trolley (one fire and no injuries for each) during

mining, mucking, transportation, and flame cutting/welding

activities. The Ewhr value was 41 × 106

 hr. The most common

ignition sources were hydraulic fluid sprayed onto equipment

hot surfaces, followed by electrical short/arcing and flame

cutting/welding spark/slag. The methods of detection were operators who saw flames/flash fires and operators/miners/welders

who saw smoke or sparks. The most commonly used suppression methods were dry chemical powder, rock dust, and portable

fire extinguishers (one equipment fire was not extinguished).

A machine fire suppression system was discharged once; in

another instance, the system was not activated.

During 1996-1997, there were nine fires and five injuries. The

equipment involved included scoops (three fires and four injuries),

loaders, and haulage/utility trucks (two fires and no injuries for

each), a drill (one fire and one injury), and a locomotive (one fire

and no injuries) during mucking, loading, haulage/utility, mining,

drilling, and transportation activities. The Ewhr was 44 × 106

 hr

(Irr = 0.027). The most common ignition sources were hydraulic

fluid sprayed onto equipment hot surfaces followed by flammable

liquid/fuel/motor oil on hot surfaces and electrical short/arcing.

The most frequent methods of detection were operators who saw

flames/flash fires and operators/miners who saw smoke. The

most commonly used suppression methods were dry chemical

powder, rock dust, water, and portable fire extinguishers. A

machine fire suppression system was discharged once; however,

the discharge occurred late because of system late response.

During 1998-1999, there were three fires and no injuries. The

equipment involved included a power scaler, scoop, and

locomotive (one fire and no injuries for each) during mining and

idle activities. The Ewhr value was 40 × 106

 hr. The ignition

sources were hydraulic fluid sprayed onto equipment hot surfaces

followed by electrical short/arcing. The methods of detection

were operators who saw flames/flash fires and miners who saw

smoke. The suppression methods used were dry chemical

powder, rock dust, water, and portable fire extinguishers.

Table 48 shows the number of fire injuries per number of fires

causing injuries and total fires by year, ignition source, equipment

involved, and location. The highest number of fire injuries was

recorded in 1997 (four fire injuries caused by one equipment fire).

These involved scoops during hydraulic fluid fires.

Table 45.–Number of mobile equipment fires for underground metal/nonmetal and stone mines by ignition source, 

equipment involved, and time period, 1990-1999

Time period

Equipment Ignition source 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Power scaler . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces ..... – – 1 – 1 2

Loader . . . . . . . . . . . . . Flammable liquid/fuel oil on hot surfaces . . . . . . . . . – – – 2 – 2

Hydraulic fluid/fuel on equipment hot surfaces ..... – – 1 – – 1

Scoop . . . . . . . . . . . . . . Motor oil on hot surfaces . . . . . . . . . . . . . . . . . . . . . – 1 – 1 – 2

Hydraulic fluid/fuel on equipment hot surfaces ..... – – – 2 1 3

Drill . . . . . . . . . . . . . . . . Overheated oil1 ............................. – – – 1 – 1

Haulage/utility truck . . . Hydraulic fluid/fuel on equipment hot surfaces ..... – 3 – 1 – 4

Fuel oil on hot surfaces . . . . . . . . . . . . . . . . . . . . . . – – – 1 – 1

Shuttle car . . . . . . . . . . Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . . . . – 1 – – – 1

Ore cart . . . . . . . . . . . . . Hydraulic fluid on equipment hot surfaces ........ 1 – – – – 1

Locomotive . . . . . . . . . . Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . . . . 1 – – 1 1 3

Trolley . . . . . . . . . . . . . . Electrical short/arcing . . . . . . . . . . . . . . . . . . . . . . . . – – 1 – – 1

Crane . . . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot surfaces ..... 1 – – – – 1

Slusher bucket . . . . . . . Flame cutting/welding spark/slag . . . . . . . . . . . . . . . – – 1 – – 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 5 4 9 3 24 1

Due to compressor malfunction.
41

Table 46.–Number of mobile equipment fires for underground metal/nonmetal and stone mines

by method of detection, equipment involved, and time period, 1990-1999

Time period

Equipment Method of detection 90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Power scaler . . . . . . . . . Visual-flames/flash fire . . . – – 1 – 1 2

Loader . . . . . . . . . . . . . Visual-flames/flash fire . . . – – 1 – – 1

Visual-smoke . . . . . . . . . . – – – 2 – 2

Scoop . . . . . . . . . . . . . . Visual-flames/flash fire . . . – – – 2 – 2

Visual-smoke . . . . . . . . . . – 1 – 1 1 3

Drill . . . . . . . . . . . . . . . . Visual-smoke . . . . . . . . . . – – – 1 – 1

Haulage/utility/truck . . . Visual-flames/flash fire . . . – 3 – 1 – 4

Visual-smoke . . . . . . . . . . – – – 1 – 1

Shuttle car . . . . . . . . . . Power loss . . . . . . . . . . . . – 1 – – – 1

Ore cart . . . . . . . . . . . . . Visual-flames/flash fire . . . 1 – – – – 1

Locomotive . . . . . . . . . . Visual-smoke . . . . . . . . . . 1 – – 1 1 3

Trolley . . . . . . . . . . . . . . Visual-smoke . . . . . . . . . . – – 1 – – 1

Crane . . . . . . . . . . . . . . Undetected ............ 1 – – – - 1

Slusherbucket . . . . . . . . Visual-sparks . . . . . . . . . . – – 1 – – 1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 5 4 9 3 24

Table 47.–Number of mobile equipment fires for underground metal/nonmetal and stone mines by suppression method,

 equipment involved, and time period, 1990-1999

Equipment Suppression method

Time period

90-91 92-93 94-95 96-97 98-99 90-99

No. fires No. fires No. fires No. fires No. fires No. fires

Power scaler . . . . . . . . Destroyed/heavily damaged1 ............ – – 1––1

FE-dry chemical powder-rock dust2 ....... – – ––11

Loader . . . . . . . . . . . . FE-FSS-dry chemical powder-rock dust3 ... – – 1 – – 1

FE-dry chemical powder-rock dust-water2 .. – – – 2 – 2

Scoop . . . . . . . . . . . . . FE-FSS-HD4 ......................... – – –1–1

Destroyed/heavily damaged1 ............ – 1 –––1

FE-rock dust-dry chemical powder2 ....... – – –213

Drill . . . . . . . . . . . . . . . Portable fire extinguisher ............... – – –1–1

Haulage/utility truck . . FE-rock dust-dry chemical powder-water2 .. – 2 – 1 – 3

Portable fire extinguisher ............... – – –1–1

FE-rock dust-water . . . . . . . . . . . . . . . . . . . . – 1 –––1

Shuttle car . . . . . . . . . FE–dry chemical powder-water2 .......... – 1 –––1

Ore cart . . . . . . . . . . . . FE-rock dust-water . . . . . . . . . . . . . . . . . . . . 1 – –––1

Locomotive . . . . . . . . . Dry chemical powder-water2 ............. – – ––11

Portable fire extinguisher ............... 1 – –1–2

Trolley . . . . . . . . . . . . . Portable fire extinguisher ............... – – 1––1

Crane . . . . . . . . . . . . . Destroyed-heavily damaged1 ............ 1 – –––1

Slusher bucket . . . . . . Manual-FE5 .......................... – – 1––1

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 5 4 9 3 24

FE Portable fire extinguisher.

FSS Machine fire suppression system.

HD Heavily damaged.

1

Usually due to failed fire suppression methods or undetected fires (two FSS activation failures). 2

Methods used by mine rescue teams.

3

Methods used by mine rescue teams following available FSS discharge by operator. 4

Due to failed fire suppression methods.

5

Methods used by welders to extinguish clothing fires.

Table 48.–Number of fire injuries per number of mobile equipment fires causing injuries and total fires in underground

metal/nonmetal and stone mines by year, ignition source, equipment involved, and location, 1990-1999

Year

No. fires

causing

injuries

No. total

fires

No. fire

injuries Ignition source Equipment Location

1990 . . . . 1 1 1 Hydraulic fluid/fuel on equipment hot surfaces . . . Ore cart . . . . . Transportation area.

1991 .... – 2 –

1992 . . . . 1 2 1 Motor fuel on hot surfaces . . . . . . . . . . . . . . . . . . Scoop . . . . . . Mining area.

1993 .... – 3 – – – –

1994 .... – 3 – – – –

1995 .... – 1 – – – –

1996 . . . . 1 5 1 Overheated oil . . . . . . . . . . . . . . . . . . . . . . . . . . . Drill . . . . . . . . Drilling area.

1997 . . . . 1 4 4 Hydraulic fluid/fuel on equipment hot surfaces . . . Scoop . . . . . . Mining area.

1998 .... – 1 – – – –

1999 .... – 2 – – – –

Total . . . . 4 24 7
42

SUMMARY OF MAJOR MOBILE EQUIPMENT FIRE AND FIRE INJURY FINDINGS

FOR ALL COAL MINING CATEGORIES

Major mobile equipment fire and fire injury findings for all

coal mining categories during 1990-1999 are reported in tables

49-50. Data during the five 2-year time periods (figure 19) are

discussed below.

For these categories, there was a grand total of 197 equipment fires during 1990-1999; 77 injuries were caused by 76 of

those fires. The Ewhr value was 2,070 × 106

 hr (Irr = 0.007);

the CP value (surface and underground coal mines only) was

10,363 × 106

 st (Frr = 0.019). In all, 10 pieces of equipment

(5%) involved in the fires had machine fire suppression systems.

Nineteen equipment fires (9%) were not extinguished due to the

failure of fire-fighting methods, late fire detection, undetected

fires, or fire size, and the equipment involved was destroyed or

heavily damaged. The greatest number of fires and injuries

occurred at surface mines; the highest risk rates were also

calculated for these operations.

For all surface coal mining categories, the largest number of

equipment fires was caused by hydraulic fluid/fuel (94 fires or

48%, with 30 injuries) sprayed onto equipment hot surfaces.

Most of these fires, although detected by the operators when

they started, grew out of control because of the continuous flow

of fluids from pumps and tanks due to engine shutoff failure,

lack of an emergency line drainage system, difficulty in

reaching emergency systems at ground level due to flames

engulfing the area, or lack of effective and rapid local firefighting response capabilities. At least nine times the cab was

suddenly engulfed in flames, most likely due to the ignition of

flammable vapors and mists that formed and penetrated the cab,

and forced the operator to exit under difficult conditions. In

four instances, upon machine fire suppression activation, the

flames continued to be fueled by the flow of fluids from pumps

and tanks because of engine shutoff failure or lack of an

emergency line drainage system. Dual activation (nine

activations) of machine fire suppression and engine shutoff

systems succeeded in temporarily abating the flames, which

reignited, fueled by the continuous flow of pressurized fluids

entrapped in the lines (not affected by the engine shutoff

operation). Other ignition sources were flame cutting/welding

spark/slag (43 or 22%; at least once, this source caused a

hydraulic fluid fire), electrical short/arcing (25 fires or 13%;

at least once, this source caused a hydraulic fluid fire),

flammable liquid/refueling fuel/fuel oil on hot surfaces (10 fires

or 5%), and engine/mechanical/malfunctions/friction/explosion

(9 fires or 5%). Other fires and injuries were caused by heat

sources, overheated oil on hot surfaces due to compressor

malfunction, and battery explosions.

In underground coal mines, the largest number of fires was

caused by electrical short/arcing (13 fires or 7%) and 1 hydraulic fuel fire.

Fire brigades and fire departments at surface mines, handicapped by travel distances, fought the hydraulic fluid/fuel fires

with foam, dry chemical powder, and water. Mine rescue teams

in underground mines, which were often severely hindered by

smoke, fought the electrical and hydraulic fluid fires with foam,

dry chemical powder, rock dust, and water. Seventeen equipment fires (9%) were not extinguished and burned themselves

out because of failed fire suppression and fire-fighting methods,

late fire detection, undetected fires, or fire size, and the

equipment involved was destroyed or heavily damaged.

For all coal mining categories, data during the five time

periods show a decrease in the number of equipment fires and

injuries, accompanied by a decline in employees' working hours

and a small increase in coal production (this increase refers to

surface and underground coal mines only). However, some

observations common to all categories are reported below.

1. At surface coal mines, there were 140 fires; 56 of those

fires caused 56 injuries. The Ewhr value was 729 × 106

 hr (Irr

= 0.015); the CP value was 6,355 × 106

 st (Frr = 0.022). The

ignition sources that caused most of the equipment fires were

hydraulic fluid/fuel (77 fires or 55%) sprayed onto equipment

hot surfaces due to ruptured lines and failed fittings and gaskets.

Other ignition sources were flame cutting/welding spark/slag,

electrical short/arcing, engine/mechanical malfunctions/friction/

explosion, and flammable liquids on hot surfaces. The fires

were easily extinguished with portable fire extinguishers. Five

pieces of equipment (3.6%) involved in these fires had machine

fire suppression systems. Dual activation (three activations) of

machine fire suppression and engine shutoff systems succeeded

in abating the flames temporarily. However, the flames reignited, fueled by the flow of fluids entrapped in the lines. In

two other instances, the flames continued to be fueled by the

flow of fluids from the pump because of engine shutoff failure.

Most of the hydraulic fluid/fuel fires, although detected by the

operators when they started, grew out of control (requiring 15

fire-fighting interventions) because of the continuous flow of

hydraulic fluids from the pump and tanks due to engine shutoff

failure, lack of an emergency line drainage system, difficulty in

reaching emergency systems at ground level, or lack of effective

and rapid local fire-fighting response capabilities. At least three

times, flammable vapors and mists penetrated the cab and

ignites. Fire brigades and fire departments, often handicapped

by travel distances, fought the hydraulic fluid/fuel fires with

foam, dry chemical powder, and water. Ten equipment fires

were not extinguished because of failed fire-fighting methods,

late fire detection, undetected fires, or fire size. The equipment

involved in the fires included haulage/utility trucks, dozers,

loaders, shovels, and drills mostly during working activities.

The ignition sources that caused most of the injuries were

hydraulic fluid/fuel sprayed onto equipment hot surfaces, flame

cutting/welding spark/slag, flammable liquids on hot surfaces,

and engine/mechanical malfunctions. The equipment involved

in injuries included trucks, shovels, dozers, and loaders at

haulage, mining, loading, flame cutting/welding, and

maintenance areas.
43

Equipment fires and injuries decreased sharply throughout

the five time periods, accompanied by a decline in employees'

working hours and a small increase in coal production.

2. At surface of underground coal mines, there were

14 fires; 4 of those fires caused 4 injuries. The Ewhr value was

97 × 106

 hr (Irr = 0.008). The ignition sources that caused most

of the equipment fires were hydraulic fluid/fuel (10 fires or

71%) sprayed onto equipment hot surfaces, followed by flame

cutting/welding spark/slag (at least once this source caused a

hydraulic fluid fire), electrical short/arcing, and overheated oil.

Two pieces of equipment (14%) involved in the fires had

machine fire suppression systems. Dual activation (one activation) of machine fire suppression and engine shutoff systems

failed to suppress the fires due to the flow of fluids entrapped in

the lines. Most of the hydraulic fluid/fuel fires, although detected by the operators when they started, grew out of control

(requiring at least one fire-fighting intervention) because of the

continuous flow of fluids from pumps and tanks due to engine

shutoff failure, lack of an emergency line drainage system,

difficulty in reaching available emergency systems at ground

level, or lack of effective and rapid local fire-fighting response

capabilities. At least twice, flammable vapors and mists penetrated the cab and ignited. Fire brigades and fire department

fought the hydraulic fluid/fuel fires with foam, dry chemical

powder, and water. Two equipment fires were not extinguished

because of failed fire suppression and fire-fighting methods.

The equipment involved included scrapers, loaders, dozers, and

hoists mostly during working activities.

The ignition sources that caused the injuries were flame

cutting/welding spark/slag, hydraulic fluid/fuel sprayed onto

equipment hot surfaces, and battery explosion. The equipment

involved in injuries included a haulage truck, highlift, tractor,

and loader at flame cutting/welding and loading areas and at

charging stations.

Equipment fires and injuries decreased slightly during most

of the five time periods, accompanied by a small decline in

employees' working hours.

3. At coal prep plants, there were 17 fires; 6 of those fires

caused 7 injuries. The Ewhr value was 241 × 106

 hr (Irr

= 0.006). The ignition sources that caused most of the equipment fires were hydraulic fluid/fuel (7 fires or 41%) sprayed

onto equipment hot surfaces, followed by engine/mechanical

malfunctions, flammable liquid/fuel oil on hot surfaces, and

electrical short/arcing. Most of the hydraulic fluid/fuel fires

grew out of control (requiring at least one fire-fighting intervention) because of the continuous flow of fluids from pumps

and tanks due to engine shutoff failure, lack of an emergency

line drainage system, difficulty in reaching available emergency

systems at ground level, or lack of effective and rapid local firefighting response capabilities. At least twice, flammable vapors

and mists penetrated the cab and ignited. None of the

equipment involved in the fires had machine fire suppression

systems. Fire departments fought the hydraulic fluid/fuel fires

with dry chemical powder and water. Three equipment fires

were not extinguished because of late detection, undetected

fires, or fire size. The equipment involved included loaders,

trucks, and dozers mostly during working activities.

The ignition sources that caused most of the injuries were

hydraulic fluid/fuel sprayed onto equipment hot surfaces and

mechanical malfunction. The equipment involved in fire

injuries included loaders and trucks at loading, haulage, and

maintenance areas.

Equipment fires decreased slightly throughout the five time

periods, accompanied by a decline in employees' working hours.

Fire injuries increased slightly during 1994-1995.

4. In underground coal mines, there were 26 fires; 10 of

those fires caused 10 injuries. The Ewhr value was 1,003

× 106

 hr (Irr = 0.002); the CP value was 4,008 × 106 st (Frr

= 0.007). The ignition source that caused most of the equipment

fires was electrical short/arcing of wires and cables (13 fires or

50%; at least once, this source caused a hydraulic fluid fire).

Most of the underground equipment is electrically powered.

Other ignition sources were flame cutting/welding spark/slag,

refueling fuel/fuel oil on hot surfaces, mechanical malfunction/

friction, heat source, hydraulic fluid sprayed onto equipment hot

surfaces, and overheated oil. Three pieces of equipment (12%)

involved in the fires had machine fire suppression systems.

Dual activation (two activations) of machine fire suppression/

motor deenergization systems succeeded in temporarily

containing the fires. In another instance, the machine

suppression system failed to activate because of clogged lines.

Upon mine/section evacuation, mine rescue teams (required at

least five times), which were often severely hindered by dense

smoke in trying to reach the fire location, fought the electrical

(three fires), hydraulic fluid (one fire), and heat source fires (one

fire) with dry chemical powder, rock dust, and water. Two

equipment fires were not extinguished because of failed fire

suppression methods and late fire detection.

The equipment involved included scoops, bolters, shuttle

cars, and continuous miners during mining, bolting, transportation, maintenance, and flame cutting/welding activities.

The ignition sources that caused most of the fire injuries were

electrical short/arcing, flame cutting/welding spark/slag, heat

sources, and flammable liquids on hot surfaces. The equipment

involved in fire injuries included scoops, shuttle cars, bolters,

and railrunners at mining faces, crosscuts, charging stations, rail

track areas, and flame cutting/welding areas.

Equipment fires and injuries decreased during 1996-1997,

then increased during 1998-1999, accompanied by a sharp

decline in employees' working hours and small changes in coal

production.
44

Table 49.–Major mobile equipment fire findings for all coal mining categories, 1990-1999

Variables Surface coal mines Surface of underground coal mines Coal preparation plants 

GT: No. fires:

CP 106 st:

Frr:No. fires causing injuries:

197

10,363

0.019

76

No. fires:CP 106 st

Frr:No. fires causing injuries:

140

6,355

0.022

56

No. fires:No. fires causing injuries:

14

4

No. fires: No. fires causing injuries:

17

6

NC

FN

Ignition source . . . . . . . . . . . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot

 surfaces.Flame cutting/welding spark/slagElectrical short/arcingEngine/mechanical malfunction/ friction/explosion.

Hydraulic fluid/fuel on equipment hot surfaces.Flame cutting/welding spark/slagElectrical short/arcingOverheated oil

Hydraulic fluid/fuel on equipment hot surfaces.Engine/mechanical malfunctions.Flammable liquid/fuel oil on hot surfaces.

EFMH s

Method of detection . . . . . . . . . . . . . . . . . . Visual-flames/flash fire

Visual-sparksVisual-smokePopping sound

Visual-flames/flash fireVisual-sparksVisual-smokeLate detection-smoke

Visual-flames/flash fireVisual-smokeLate detection-smokeVisual-dim lights

VVVLa

Suppression method . . . . . . . . . . . . . . . . . FE-foam-DCP-water

Manual/FEFE-DCP-waterFE-FSS-DCP-water

FE-foam-water-DCPFE-FSS-foam-HDPortable fire extinguisherManual/FE

FE-DCP/waterPortable fire extinguisherManualFE/water

FFPF

Equipment . . . . . . . . . . . . . . . . . . . . . . . . . Trucks

DozersLoadersShovels/bucket

ScrapersLoadersDozersHoists

LoadersTrucksDozers

SSBC

Location . . . . . . . . . . . . . . . . . . . . . . . . . . . Equipment working areas1

Flame cutting/welding areas2Maintenance areas

Equipment working areas1

Flame cutting/welding areas2

Equipment working areas1Flame cutting/welding areas2

EMF

DCP Dry chemical powder.FE Portable fire extinguisher.FSS Machine fire suppression system.GT Grand total.HD Heavily damaged.1Includes haulage/utility, mining, loading, hoisting, bolting, drilling, mucking, and transport areas.2Includes working, mining, and maintenance areas.

NOTE.–Variables are listed in descending order of occurrence.
Table 50.–Major mobile equipment fire injury findings for all coal mining categories, 1990-1999.

Variables Surface coal mines Surface of underground coal mines Coal preparation plants 

GT: No. fire injuries:

Ewhr,106 hr:

Irr:

77

2,070

0.007

No. fire injuries:Ewhr, 106 hr:

Irr:

56

729

0.015

No. fire injuries:Ewhr, 106 hr:

Irr:

4

97

0.008

No. fire injuries: Ewh, 106 hr: 

Irr: 

7

241

0.006

Ignition source . . . . . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot

 surfaces.Flame cutting/welding spark/slagFlammable liquid on hot surfacesEngine/mechanical malfunctions

Flame cutting/welding spark/slagHydraulic fluid/fuel on equipment hot surfaces.Battery explosion

Hydraulic fluid/fuel on equipment hot surfaces.Mechanical malfunction

Method of detection . . . . . . . . . . . . Visual-flames/flash fire

Visual-sparksVisual-flames/explosionVisual/smoke

Visual-sparksVisual-flames/flash firesVisual-smoke

Visual-flames/flash fireVisual-smoke

Suppression method . . . . . . . . . . . FE-foam-DCP-water

Manual/FEPortable fire extinguisherFE-DCP-water

Manual/FEFE-FSS-HDFE-foam-DCP-waterPortable fire extinguisher

FE-DCP-waterPortable fire extinguisher

Equipment . . . . . . . . . . . . . . . . . . . Trucks

ShovelsDozersLoaders

TrucksHighliftsTractorsLoaders

LoadersTrucks

Location . . . . . . . . . . . . . . . . . . . . . Flame cutting/welding areas1

Equipment working areas2Maintenance areas

Flame cutting/welding areas1

Charging stationEquipment working areas2

Equipment working areas2Maintenance areas

DCP Dry chemical powder.FE Portable fire extinguisher.FSS Machine fire suppression system.GT Grand total.HD Heavily damaged.

1Includes working, mining, and maintenance areas. 2Includes haulage, mining, and loading areas.

NOTE.–Variables are listed in descending order of occurrence.
46

Figure 19.–Mobile equipment fires, injuries, risk rates, employees' working hours, and coal production (coal production for surface and

underground coal mines only) for all coal mining categories by time period, 1990-1999.

SUMMARY OF MAJOR MOBILE EQUIPMENT FIRE AND FIRE INJURY FINDINGS

FOR ALL METAL/NONMETAL MINING CATEGORIES

Major mobile equipment fire and fire injury findings for all

metal/nonmetal mining categories during 1990-1999 are reported in tables 51-52. Data during the five 2-year time periods

(figure 20) are discussed below.

For these categories, there was a grand total of 142

equipment fires during 1990-1999; 82 injuries and 2 fatalities

were caused by 80 of those fires (Ewhr = 3,001 × 106

 hr; Irr

= 0.006). In all, 10 pieces of equipment (7%) involved in the

fires had machine fire suppression systems. 

The greatest number of fires and injuries occurred at surface

mines; the highest risk rates were also calculated for these

operations. 

For all metal/nonmetal mining categories, the greatest

number of equipment fires and fire injuries was caused by

hydraulic fluid/fuel (77 fires or 54%, with 42 injuries) sprayed

onto equipment hot surfaces. Fire-resistant hydraulic fluid is not

required for equipment use at all metal/nonmetal operations.

Most of the hydraulic fluid/fuel fires, although detected by the

operators when they started, grew out of control (requiring at

least 7 fire-fighting interventions at surface operations and

10 mine rescue interventions in underground mines) because of

the continuous flow of fluids from pumps and tanks due to

engine shutoff failure, lack of an emergency line drainage

system, difficulty in reaching available emergency systems at

ground level due to flames engulfing the area, or lack of

effective and rapid local fire-fighting response capabilities. On

at least seven occasions the cab was suddenly engulfed in

flames most likely due to the ignition of flammable vapors and

mists that formed and penetrated the cab during the spraying of

hydraulic fluid/fuel sprayed onto equipment hot surfaces. Dual

activation (two activations) of the machine fire suppression and

engine shutoff systems succeeded in abating the fires

temporarily. However, the flames reignited, fueled by the flow

of fluids entrapped in the lines.

In five other instances, the flames continued to be fueled by

the flow of fluids from the pump because of engine shutoff

failure (one fatality); in three other instances, the systems were

not activated. Once, the system discharged automatically, undetected by the operator (one fatality), who continued to operate

the rig until the flames suddenly engulfed the cab. Other ignition sources were flame cutting/welding spark/slag (17 fires

or 12%), flammable liquid/refueling fuel/fuel/motor oil on hot

surfaces/collision (21 fires or 15%), electrical short/arcing (14

fires or 10%), and overheated oil due to compressor malfunction

(6 fires or 4%). Fire brigades and fire department at surface

mines, handicapped by travel distances, fought the hydraulic

fluid/fuel fires with foam, dry chemical powder, and water.

Mine rescue teams in underground mines, which were often

hindered by heavy smoke, fought the hydraulic fluid/fuel fires

with dry chemical powder, rock dust, and water. Fourteen

equipment fires (10%) were not extinguished because of failure

of fire suppression and fire-fighting methods, late fire detection,

undetected fires, or fire size. 

For all metal/nonmetal mining categories, data during the

five time periods show sharp increases followed by sharp

decreases in the number of equipment fires and fire injuries

throughout the periods, accompanied by small changes in

employees' working hours. However, some observations

common to all mining categories are reported below.
47

1. At surface metal/nonmetal mines, there were 49 fires; 24

of those fires caused 24 injuries and 1 fatality. The Ewhr value

was 467 × 106

 hr (Irr=0.01). The ignition sources that caused

most of the equipment fires were hydraulic fluid/fuel (33 fires

or 67%) sprayed onto equipment hot surfaces due to ruptured

lines and failed fittings and gaskets. This was followed by

flame cutting/welding spark/slag, flammable liquid/refueling

fuel/fuel oil on hot surfaces, and electrical short/arcing. Most of

the hydraulic fluid/fuel fires, although detected by the operators

when they started, grew out of control (requiring at least one

fire-fighting intervention) because of the continuous flow of

fluids from pumps and tanks due to engine shutoff failure, lack

of an emergency line drainage system, difficulty in activating

available emergency systems, or lack of effective and rapid local

fire-fighting response capabilities. At least twice, flammable

vapors and mists penetrated the cab and ignited. Five pieces of

equipment (10%) involved in the fires had machine fire

suppression systems. Dual activation (one activation) of

machine fire suppression and engine shutoff systems succeeded

in abating temporarily the flames. However, the flames

reignited, fueled by the fluids entrapped in the lines. In one

instance, the flames continued to be fueled by the flow of fluids

from the pump because of engine shutoff failure. In another

instance, the machine fire suppression system discharged

automatically, undetected by the operator (one fatality), who

continued to operate the rig until the flames suddenly engulfed

the cab. Fire brigades and fire departments, handicapped by

travel distances, fought the hydraulic fluid/fuel fires with foam,

dry chemical powder, and water. Seven equipment fires were

not extinguished because of failed fire suppression and firefighting methods, late fire detection, undetected fires, or fire

size. The equipment involved included haulage/utility trucks,

shovels, loaders, and drills mostly during working activities.

The ignition sources that caused most of the injuries were

hydraulic fluid/fuel sprayed onto equipment hot surfaces, electrical short/arcing, flame cutting/welding spark/slag, and refueling fuel/flammable liquid on hot surfaces. The equipment

involved in injuries included trucks, loaders, shovels, and dozers

mostly at haulage, loading, mining, maintenance, and flame

cutting/welding areas.

Equipment fires increased sharply during 1992-1993 (the

number of fire injuries stayed steady during this period), then

decreased during subsequent periods, accompanied by a small

decline in employees' working hours.

2. At surface sand and gravel and stone mines, there were

46 fires; 36 of those fires caused 35 injuries and 1 fatality. The

Ewhr value was 1,101 × 106

 hr (Irr = 0.006). The ignition

sources that caused most of the equipment fires were hydraulic

fluid/fuel (25 fires or 54%) sprayed onto equipment hot

surfaces, followed by flammable liquid/refueling fuel/oil on hot

surfaces, flame cutting/welding spark/slag, electrical

short/arcing, and mechanical malfunction/friction/collision.

None of the equipment involved in the fires had machine fire

suppression systems. Most of the hydraulic fluid/fuel fires grew

out of control (requiring at least four fire-fighting interventions)

because of the continuous flow of fluids from pumps and tanks

due to engine shutoff failure, lack of an emergency line drainage

system, difficulty in reaching available emergency systems at

ground level, or lack of effective and rapid local fire-fighting

response capabilities. At least twice flammable vapors and

mists penetrated the cab and ignited. Fire departments fought

the hydraulic fluid/fuel fires with dry chemical powder and

water. Four equipment fires involving six pieces of equipment

were not extinguished because of undetected fires or fire size.

The equipment included trucks, loaders, dozers, and dredges

during haulage, loading, mining, dredging, flame

cutting/welding, and maintenance activities.

The ignition sources that caused most of the fire injuries were

hydraulic fluid/fuel sprayed onto equipment hot surfaces, followed by flame cutting/welding/spark/slag, refueling fuel/

flammable liquid on hot surfaces, and electrical short/arcing.

The equipment involved in fire injuries included trucks, loaders,

dozers, and dredges at haulage, loading, mining, dredging, flame

cutting/welding, and maintenance areas.

Equipment fires and fire injuries increased sharply during

1992-1993, then decreased throughout subsequent periods

(especially 1998-1999), accompanied by a small increase in

employees' working hours.

3. At metal/nonmetal and stone mills, there were 23 fires;

16 of those fires caused 16 injuries. The Ewhr value was 1,219

× 106

 hr (Irr = 0.003). The ignition sources that caused most of

the equipment fires were hydraulic fluid/fuel (seven fires or

30%) sprayed onto equipment hot surfaces, followed by flame

cutting/welding spark/slag, flammable liquid on hot surfaces,

electrical short/arcing, overheated oil and transmission oil on

hot surfaces and hot material. Most of the hydraulic fluid/fuel

fires, although detected by the operators when they started, grew

out of control (requiring at least twice fire-fighting interventions) because of the continuous flow of fluids from pumps and

tanks due to engine shutoff failure, lack of an emergency line

drainage system, difficulty in reaching available emergency

systems at ground level, or lack of effective and rapid local firefighting response capabilities. On at least one occasion,

flammable vapors and mists penetrated the cab and ignited. 

One piece of equipment (4%) involved in the fires had a machine fire suppression system. However, activation of the

machine fire suppression system was ineffective in suppressing

the hydraulic fluid/fuel fire because of engine shutoff failure.

Fire brigades and fire departments fought the hydraulic

fluid/fuel fires with foam, dry chemical powder, and water. One

equipment fire was not extinguished because the fire was

undetected, and the equipment involved was destroyed. The

equipment included loaders, haulage/utility trucks, shovels, and

dozers during working and maintenance activities.
48

Figure 20.—Mobile equipment fires, injuries, risk rates, and employees' working hours for all metal/nonmetal mining categories by time

period, 1990-1999.

The ignition sources that caused most of the injuries were

hydraulic fluid/fuel sprayed onto equipment hot surfaces, flame

cutting/welding spark/slag, flammable liquid on hot surfaces,

and electrical short/arcing. The equipment involved in injuries

included loaders, trucks, dozers, and drills at loading, haulage,

drilling, flame cutting/welding, and maintenance areas.

Equipment fires decreased sharply during 1994-1995, followed by small increases and decreases during subsequent

periods. However, fire injuries decreased steadily during most

of the periods, accompanied by a small decline in employees'

working hours.

4. In underground metal/nonmetal and stone mines, there

were 24 fires; 4 of those fires caused 7 injuries. The Ewhr value

was 214 × 106

 hr (Irr = 0.007). The ignition sources that caused

most of the equipment fires were hydraulic fluid (12 fires or

50%) sprayed onto equipment hot surfaces, followed by electrical short/arcing of wires and cables, flammable liquid/fuel/

motor oil, overheated oil, and flame cutting/welding spark/slag.

Most of the hydraulic fluid fires, although detected by the

operators when they started, grew out of control (requiring at

least 10 fire-fighting interventions) because of the continuous

flow of fluids from pumps and tanks due to engine shutoff

failure, lack of emergency line drainage systems, or lack of

effective and rapid local fire-fighting response

capabilities. At least twice, flammable vapors and mists

penetrated the cab and ignited. Four pieces of equipment (17%)

involved in the fires had machine fire suppression systems.

Dual activation (one activation) of machine fire suppression

system and engine shutoff systems succeeded in containing the

fire. In another instance, the flames continued to be fueled by

the flow of fluids from the pump because of engine shutoff

failure. Once the machine fire suppression system failed to

activate promptly. Upon mine/section evacuation, mine rescue

teams (required 20 times), which were often severely hindered

by dense smoke in trying to reach the fire location, fought the

hydraulic fluid and electrical fires with dry chemical powder,

rock dust, and water. Four equipment fires were not

extinguished because of failed fire suppression methods and

undetected fires. The equipment included scoops, trucks,

locomotives, and loaders during mining, mucking, haulage, and

loading activities.

The ignition sources that caused most of the injuries were

hydraulic fluid sprayed onto equipment hot surfaces, overheated

oil, and motor oil on hot surfaces. The equipment involved in

injuries included scoops, ore carts, and drills at mining, drilling,

and transportation areas.

Equipment fires and fire injuries increased sharply during

1996-1997, then decreased sharply during 1998-1999, accompanied by small changes in employees' working hours.
Table 51.–Major mobile equipment fire findings for all metal/nonmetal mining categories, 1990-1999

Variables Surface metal/nonmetal mines Surface sand/gravel and stone mines Metal/nonmetal and stone mills 

GT: No. fires: 142

No fires causing injuries: 80

No. fires: 

49

No. fires causing injuries:

24

No. fires: 46No. fires causing injuries: 36

No. fires: 23No. fires causing injuries: 16

NoNo

Ignition source . . . . . . . . . . . . . . . Hydraulic fluid/fuel on

equipment hot surfaces.Flame cutting/weldingspark/slagRefueling fuel/flammable liquid/ fuel oil on hot surfaces.Electrical short/arcing

Hydraulic fluid/fuel on equipment hot surfaces.Refueling fuel/flammable liquid/fuel oil on hot surfaces.Flame cutting/welding spark/slagElectrical short/arcing

Hydraulic fluid/fuel on equipment hot surfaces.Flame cutting/welding spark/slagFlammable liquid/fuel oil on hot surfaces/ collision.Overheated oil/transmission oil on hot surfaces.

Hy hElFl hOv

Method of detection . . . . . . . . . . . Visual-flames/flash fire

Visual-smokeVisual-sparksPower loss/power trip

Visual-flames/flash fireVisual-sparksVisual-smokeLate detection-smoke

Visual-flames/flash fireVisual-sparksVisual-smokeLate det./smoke

ViViPoVi

Suppression method . . . . . . . . . . FE-foam-DCP-water

Portable fire extinguisherManual/FEFE-FSS-DCP-water

FE-water-DCPPortable fire extinguisherManual/FE

Portable fire extinguisherFE-foam-DCP-waterManual/FEFE-FSS-DCP-water

FEPoFEM

Equipment . . . . . . . . . . . . . . . . . . Trucks

ShovelsDrillsLoaders

TrucksLoadersDozersDredges

LoadersTrucksShovelsDozers

ScTrTrLo

Location . . . . . . . . . . . . . . . . . . . . Equipment working areas1

Flame cutting/welding areas2Maintenance areas

Equipment working areas1

Maintenance areasFlame cutting/welding areas2

Equipment working areas1Flame cutting/welding areas2Maintenance areas

Eq

TrFlM

DCP Dry chemical powder.FE Portable fire extinguisher.FSS Machine fire suppression system. GT Grand total.

1Includes haulage, mining, drilling, loading, mucking, and transport areas.2Includes working, mining, and maintenance areas.

NOTE.–Variables are listed in descending order of occurrence.
50

Table 52.–Major mobile equipment fire injury findings for all metal/nonmetal mining categories, 1990-1999

Variables Surface metal/nonmetal mines Surface sand/gravel and stone mines Metal/nonmetal and stone mills 

GT: No. fire injuries:

No. fire fatalities:Ewhr, 106 hr:

Irr:

82

2

3,001

0.006

No. fire injuries:No. fire fatalities:Ewhr, 106 hr:

Irr:

24

1

467

0.01

No. fire injuries:No. fire fatalities: Ewhr, 106 hr:

Irr:

35

1

1,101

0.006

No. fire injuries: Ewhr, 106 hr: 

Irr: 

16

1,219

0.003

Ignition source . . . . . . . . . . . . . . . . Hydraulic fluid/fuel on equipment hot

 surfaces.Electrical short/arcingFlame cutting/welding/spark/slagRefueling fuel/flammable liquid on hot surfaces.

Hydraulic fluid/fuel on equipment hot surfaces.Flame cutting/welding/spark/slagFlammable liquid/refueling fuel on hot surfaces.Electrical short/arcing

Hydraulic fluid/fuel on equipment hot surfaces.Flame cutting/welding spark/slagFlammable liquid on hot surfacesElectrical short/arcing

Method of detection . . . . . . . . . . . . Visual-flames/flash fire

Visual-sparksVisual-smoke

Visual-flames/flash fireVisual-sparksVisual-smoke

Visual-flames/flash fireVisual-sparksVisual-smoke

Suppression method . . . . . . . . . . . FE-foam-DCP-water

Portable fire extinguisherFE-FSS-DCPManual/FE

FE-DCP-waterPortable fire extinguisherManual/FE

FE-foam-DCP-waterFE-FSS-DCPManual/FEPortable fire extinguisher

Equipment . . . . . . . . . . . . . . . . . . . Trucks

LoadersShovelsDozers

TrucksLoadersDozersDredges

LoadersTrucksDozersDrills

Location . . . . . . . . . . . . . . . . . . . . . Equipment working areas1

Flame cutting/welding areas2Maintenance areas

Equipment working areas1

Flame cutting/welding areas2Maintenance areas

Equipment working areas1

Flame cutting/welding areas2Maintenance areas

DCP Dy chemical powder.FE Portable fire extinguisher.FSS Machine fire suppression system.GT Grand total.

1Includes haulage, loading, mining, dredging, drilling, and transport areas.2Includes working, mining, and maintenance areas.

NOTE.–Variables are listed in descending order of occurrence.
51

CONCLUSIONS

Findings show that the greatest number of equipment fires

and injuries during 1990-1999 occurred at surface mines; the

highest injury risk rate values were also calculated for these

operations. For all mining categories, there was a total of

339 fires; 159 injuries and 2 fatalities were caused by 156 of

those fires. In the future, these equipment fires and injuries may

be prevented/reduced or suppressed at their earliest stage by

improving techniques and strategies, developing new technologies, and improving safety training programs. Several

suggestions follow.

1. Schedule more frequent and more thorough inspections

of hydraulic, fuel, and electrical systems. A large number of

equipment fires were due to ruptured hydraulic/fuel lines and

failed fittings/gaskets and electrical short/arcing in power cable

systems. By scheduling more frequent and thorough inspections, potential system failures may be detected beforehand.

2. Develop new technologies for emergency engine shutoff

system and line drainage system. A large number of hydraulic

fluid/fuel fires grew out of control because of the continuous

flow of fluids from pumps and tanks due to engine shutoff

failure. Furthermore, a large number of fires, upon successful

dual activation of machine fire suppression and engine shutoff

systems, continued to be fueled by the fluids entrapped in the

lines. By developing emergency engine shutoff systems and

line drainage systems, equipment fires may be contained more

readily and the effectiveness of machine fire suppression

systems could be enhanced.

3. Develop cab fire detection and fire prevention/

suppression systems. None of the cabs involved in the fires had

fire detection and suppression systems. During the hydraulic

fluid/fuel fires, flammable vapors and mists often penetrated the

cab. These ignited violently while the operator was performing

emergency tasks, forcing the operator to exit the cab among

intense flames. By equipping the cab with fire detection and fire

prevention/suppression systems, vapor/mist concentrations

could be detected and their ignition prevented.

4. Develop effective and rapid local fire-fighting response

capabilities. Findings show that local mine personnel have inadequate fire-fighting capabilities to combat hydraulic fluid/fuel

and electrical equipment fires. Fire brigades, fire departments,

and mine rescue teams, handicapped by travel distances, were

often called to fight these fires. By training local miners to fight

equipment fires when they are detected with adequate firefighting capabilities, such as large quantities of dry chemical

powder on vehicles for ease of deployment to the fire site, these

fires could be better contained.

5. Schedule more frequent fire emergency preparedness

training for equipment operators. During equipment hydraulic

fluid/fuel fires, operators often failed to perform emergency

tasks such as activating the machine fire suppression and engine

shutoff systems. This was due mostly to lack of time and stressful conditions. By scheduling more frequent fire emergency

preparedness training sessions, operators would be able to

perform these tasks more quickly under fire conditions.

ACKNOWLEDGMENT

The author thanks Kimberly A. Mitchell, Program Operations Assistant, Disaster Prevention and Response Branch, NIOSH

Pittsburgh Research Laboratory, for computerizing all of the tables and figures in this report.

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Minneapolis, MN: U.S. Department of the Interior, Bureau of Mines, Twin

Cities Research Center, IC 9132. NTIS No. PB 87-196341.

CFR. Code of Federal regulations. Washington, DC: U.S. Government

Printing Office, Office of the Federal Register.

Johnson GA, Forshey DR [1975]. Automatic fire protection systems for

large haulage vehicles: prototype development and in-mine testing. Minneapolis, MN: U.S. Department of the Interior, Bureau of Mines, Twin Cities

Research Center, IC 8683. NTIS No. PB 246 704.

McDonald LB, Pomroy WH [1980]. A statistical analysis of coal mine fire

incidents in the United States from 1950 to 1977. Minneapolis, MN: U.S.

Department of the Interior, Bureau of Mines, Twin Cities Research Center, IC

8830. NTIS No. PB 81-148371.

MSHA [1990a]. Accident investigation report, surface coal mine,

ID 2900097, equipment fire accident, BHP Utah International, Inc., Fruitland,

NM, June 19, 1990. Denver, CO: U.S. Department of Labor, Mine Safety and

Health Administration, Office of Injury and Employment Information.

MSHA [1990b]. Injury experience in coal mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1205.

MSHA [1990c]. Injury experience in metallic mineral mines. Denver, CO:

U.S. Department of Labor, Office of Injury and Employment Information, IR 1201.

MSHA [1990d]. Injury experience in nonmetallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1202.

MSHA [1990e]. Injury experience in sand and gravel mining. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1204.

MSHA [1990f]. Injury experience in stone mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1203.
52

MSHA [1990g]. Underground coal mine, ID 1516711, equipment fire

accident, Hall Brothers Mining, Inc., Knott County, KY, July 23, 1990. Denver,

CO: U.S. Department of Labor, Mine Safety and Health Administration, Office

of Injury and Employment Information.

MSHA [1991a]. Injury experience in coal mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1207.

MSHA [1991b]. Injury experience in metallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR1208.

MSHA [1991c]. Injury experience in nonmetallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1209.

MSHA [1991d]. Injury experience in sand and gravel mining. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1211.

MSHA [1991e]. Injury experience in stone mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1210.

MSHA [1991f]. Surface coal mine, ID2401457, equipment fire accident,

Spring Creek Coal Co., Big Horn County, MT, December 26, 1991. Denver,

CO: U.S. Department of Labor, Mine Safety and Health Administration, Office

of Injury and Employment Information.

MSHA [1992a]. Injury experience in coal mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1215.

MSHA [1992b]. Injury experience in metallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1218.

MSHA [1992c]. Injury experience in nonmetallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1219.

MSHA [1992d]. Injury experience in sand and gravel mining. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1217.

MSHA [1992e]. Injury experience in stone mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1216.

MSHA [1992f]. Surface metal/nonmetal mine, ID 5001315, equipment

fire accident, Cambior, Inc., Valdez Creek, AK, December 25, 1992. Denver,

CO: U.S. Department of Labor, Mine Safety and Health Administration, Office

of Injury and Employment Information.

MSHA [1992g]. Surface of underground coal mine, ID 0503836, equipment fire accident, Twenty Mile Coal Co., Routt County, CO, June 17, 1992.

Denver, CO: U.S. Department of Labor, Mine Safety and Health Administration,

Office of Injury and Employment Information.

MSHA [1992h]. Underground nonmetal mine, ID 1600970, equipment

fire accident, Morton Salt, Inc., Iberia Parish, LA, May 19, 1992. Denver, CO:

U.S. Department of Labor, Mine Safety and Health Administration, Office of

Injury and Employment Information.

MSHA [1993a]. Injury experience in coal mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1225.

MSHA [1993b]. Injury experience in metallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1226.

MSHA [1993c]. Injury experience in nonmetallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1227.

MSHA [1993d]. Injury experience in sand and gravel mining. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1229.

MSHA [1993e]. Injury experience in stone mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1228.

MSHA [1993f]. Surface stone mine, ID 4000102, equipment fire accident,

Vulcan Materials, Inc., Davidson County, TN, July 26, 1993. Denver, CO: U.S.

Department of Labor, Mine Safety and Health Administration, Office of Injury

and Employment Information.

MSHA [1994a]. Injury experience in coal mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1232.

MSHA [1994b]. Injury experience in metallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1233.

MSHA [1994c]. Injury experience in nonmetallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1234.

MSHA [1994d]. Injury experience in sand and gravel mining. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1235.

MSHA [1994e]. Injury experience in stone mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1236.

MSHA [1994f]. Surface metal/nonmetal mine, ID 21016000, equipment

fire accident, Hibbing Taconite Co., Duluth, MN, July 27, 1994. Denver, CO:

U.S. Department of Labor, Mine Safety and Health Administration, Office of

Injury and Employment Information.

MSHA [1994g]. Surface of underground coal mine, ID01-00759,

equipment fire accident, Pittsburgh Midway Coal Co., Fayette County, AL,

March 14, 1994. Denver, CO: U.S. Department of Labor, Mine Safety and

Health Administration, Office of Injury and Employment Information.

MSHA [1994h]. Underground metal/nonmetal mine, ID 4000606, equipment fire accident, Asarco, Inc., Davidson County, TN, June 1, 1994. Denver,

CO: U.S. Department of Labor, Mine Safety and Health Administration, Office

of Injury and Employment Information.

MSHA [1994i]. Underground metal/nonmetal mine, ID 30006630, equipment fire accident, Cargill, Inc., Tompkins County, NY, June 27, 1994. Denver,

CO: U.S. Department of Labor, Mine Safety and Health Administration, Office

of Injury and Employment Information.

MSHA [1995a]. Injury experience in coal mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1242.

MSHA [1995b]. Injury experience in metallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1243.

MSHA [1995c]. Injury experience in nonmetallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1244.

MSHA [1995d]. Injury experience in sand and gravel mining. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1246.

MSHA [1995e]. Injury experience in stone mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1245.

MSHA [1995f]. Surface metal mine, ID 2601089, equipment fire accident,

Barrick Goldstrike Mines, Inc., Eureka County, NV, April 4, 1995. Denver,

CO: U.S. Department of Labor, Mine Safety and Health Administration, Office

of Injury and Employment Information.

MSHA [1995g]. Surface metal mine, ID 2601942, equipment fire accident, Newmont Mining, Inc., Humboldt County, NV, September 19, 1995.

Denver, CO: U.S. Department of Labor, Mine Safety and Health Administration,

Office of Injury and Employment Information.

MSHA [1995h]. Underground coal mine, ID 1100877, equipment fire

accident, Amax Coal Co., Wabash County, IL, October 14, 1995. Denver, CO:

U.S. Department of Labor, Mine Safety and Health Administration, Office of

Injury and Employment Information.

MSHA [1996a]. Injury experience in coal mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1253.

MSHA [1996b]. Injury experience in metallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1254.

MSHA [1996c]. Injury experience in nonmetallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1255.

MSHA [1996d]. Injury experience in sand and gravel mining. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1257.

MSHA [1996e]. Injury experience in stone mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1256.

MSHA [1996f]. Surface coal mine, ID 1200322, equipment fire accident,

Amax Coal Co., Clay County, IN, January 24, 1996. Denver, CO: U.S. Department of Labor, Mine Safety and Health Administration, Office of Injury and

Employment Information.

MSHA [1996g]. Surface coal mine, ID 4800086, equipment fire accident,

Pittsburgh Coal Co., Lincoln County, WY, April 28, 1996. Denver, CO: U.S.

Department of Labor, Mine Safety and Health Administration, Office of Injury

and Employment Information.
53

MSHA [1997a]. Injury experience in coal mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1258.

MSHA [1997b]. Injury experience in metallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1261.

MSHA [1997c]. Injury experience in nonmetallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1262.

MSHA [1997d]. Injury experience in sand and gravel mining. Denver, CO:

U.S. Department of Labor, Office of Injury and Employment Information, IR1259.

MSHA [1997e]. Injury experience in stone mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR1260.

MSHA [1997f]. Surface metal/nonmetal mine, ID 2601621, equipment

fire accident, Independence Mining Co., Elko County, NV, November 6, 1997.

Denver, CO: U.S. Department of Labor, Mine Safety and Health Administration,

Office of Injury and Employment Information.

MSHA [1997g]. Underground coal mine, ID 300063, equipment fire

accident, Cargill, Inc., Tompkins County, NY, June 12, 1997. Denver, CO: U.S.

Department of Labor, Mine Safety and Health Administration, Office of Injury

and Employment Information.

MSHA [1998a]. Injury experience in coal mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1265.

MSHA [1998b]. Injury experience in metallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1266.

MSHA [1998c]. Injury experience in nonmetallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1267.

MSHA [1998d]. Injury experience in sand and gravel mining. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR 1269.

MSHA [1998e]. Injury experience in stone mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR 1268.

MSHA [1998f]. Surface coal mine, ID4801353, equipment fire accident,

Powder River Coal Co., Campbell County, WY, March 30, 1998. Denver, CO:

U.S. Department of Labor, Mine Safety and Health Administration, Office of

Injury and Employment Information.

MSHA [1999a]. Accident investigation report: underground coal mine, ID

4602166, equipment fire accident, Sewell Seam Manag. Co., Raleigh County, WV,

July 8, 1999. Denver, CO: U.S. Department of Labor, Mine Safety and Health

Administration, Office of Injury and Employment Information.

MSHA [1999b]. Injury experience in coal mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR1272.

MSHA [1999c]. Injury experience in metallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR1273.

MSHA [1999d]. Injury experience in nonmetallic mineral mines. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR1274.

MSHA [1999e]. Injury experience in sand and gravel mining. Denver,

CO: U.S. Department of Labor, Office of Injury and Employment Information,

IR1276.

MSHA [1999f]. Injury experience in stone mining. Denver, CO: U.S.

Department of Labor, Office of Injury and Employment Information, IR1275.

Pomroy WH, Bickel KL [1980]. Automatic fire protection systems for

surface mining equipment. Minneapolis, MN: U.S. Department of the Interior,

Bureau of Mines, Twin Cities Research Center, IC8832. NTIS No. PB 81-

156937.

Pomroy WH, Carigiet AM [1995]. Analysis of underground coal mine fire

incidents in the United States from 1978 through 1992. Minneapolis, MN: U.S.

Department of the Interior, Bureau of Mines, Twin Cities Research Center,

IC9426. NTIS No. PB 95-253720.