A COMPENDIUM 

OF NIOSH MINING RESEARCH

 2001

Spokane Research Laboratory and Pittsburgh Research Laboratory

U.S. Department of Health and Human Services

Public Health Service

Centers for Disease Control and Prevention 

National Institute for Occupational Safety and Health

Washington, DC

December 2000
This document is the public domain and may be freely copied or reprinted.

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

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DHHS (NIOSH) Publication No. 2001-114
FOREWORD

Ensuring the safety and health of America’s mine workers continues to be a top priority for NIOSH. Our

research highlights over the past year indicate a strong program for addressing these issues. Our program

has been developed in close coordination with input from our stakeholders, and this input has been detailed

in previous reports. Our surveillance efforts continue to identify the areas of greatest concern, and these

areas serve as focal points for program development and review. The research highlights in this compendium

cover all mining sectors and reflect the needs and concerns of the mining community as a whole.

On a more personal note, I am privileged and honored to join NIOSH as the Associate Director of the Office

for Mine Safety and Health Research. During my brief tenure thus far, I have been most impressed by the

strong stakeholder support for the research program and will continue to foster these relationships. The

legacy left by Dr. Larry Grayson, the previous Associate Director, is one of research excellence, strong

strategic planning, and exceptional involvement with the mining community. I will continue on the path

established by Larry, and I am excited about being a part of the excellence and dedication of the NIOSH

mining family.

This compendium communicates to our many partners the current research program of the Office for Mine

Safety and Health Research. We are continually striving to enhance our communications and technology

transfer efforts, and this publication has served those purposes well. I look forward to the many exciting and

rewarding challenges of the mine safety and health research program and continued interactions and

communications with our many partners.

Lewis V. Wade, Ph.D.

Associate Director, Office for

 Mine Safety and Health Research

National Institute for Occupational

 Safety and Health
CONTENTS

Page

HEARING LOSS PREVENTION

Investigation of Technology for Hearing Loss Prevention ................................................. 1

Cross-Sectional Survey: Noise Exposure Patterns/Sources ............................................... 2

A Model Hearing Conservation Program for Coal Miners ................................................ 3

Engineering Controls for Hearing Loss Prevention ...................................................... 4

Investigation of Impulse Noise in Mining ............................................................. 5

Evaluating the Role of Positive and Negative Emotion in Promoting Hearing Conservation Behaviors

Among Coal Miners ........................................................................... 6

DUST MEASUREMENT AND CONTROL

Assessment of Personal Particulate Exposure .......................................................... 7

Dust Control in Longwall Mining ................................................................... 8

Dust Control in Surface Coal Mining ................................................................. 9

Silica Dust Control in Metal/Nonmetal Mining ......................................................... 10

Control of Silica Dust Exposures in Underground Coal Mining ............................................ 11

Development of Enhanced Spray Dust Capture Principles for Improved Silica Dust Suppression ................ 12

DIESEL EMISSION AND TOXIC SUBSTANCES

Reducing Diesel Particulate Exposure in Western Mines ................................................. 13

Diesel Engine Emissions Measurement and Analysis .................................................... 14

Safety and Health Evaluation of a Fuel Cell-Powered Four-Ton Locomotive for Underground Mining ............. 15

Diesel Partnership Research ....................................................................... 16

Portable Monitors for Airborne Metals at Mining Sites .................................................. 17

Chemical Hazards in Mining and Processing ........................................................... 18

Toxic Fumes from Blasting ........................................................................ 19

HAZARD DETECTION AND WARNING DEVICES

Safety Enhancements for Off-Highway Haulage Trucks .................................................. 20

Mobile Mining Equipment Warning Systems .......................................................... 21

Advanced Warning of Ground Stability Hazards ........................................................ 22

Overhead Power Line Contact Alarm for Mobile Equipment .............................................. 23

Investigation of Electromagnetic Precursors to Rock Bursting ............................................. 24

Smart Fire Sensors ............................................................................... 25

Detection of Bridging in Surge Piles .................................................................. 26

INJURY PREVENTION AND EQUIPMENT DESIGN

Materials Handling Accident Reduction in Underground Mines ............................................ 27

Engineering Controls for Reducing Jolting and Jarring Injuries in Surface Mines ............................... 28

Reducing Injury Risk from Jolting and Jarring on Mobile Equipment ........................................ 29

Ergonomics Interventions in Mining ................................................................. 30

Injury Prevention for Metal/Nonmetal Drilling and Bolting Operations ...................................... 31

Reducing Slipping and Falling Injuries at Surface Mines .................................................. 32

Human Factors Design for Machine Safety ............................................................ 33

Fundamental Studies in Electrical Hazards ............................................................ 34

New Technology to Increase ROPS Use on Tractors .................................................... 35
CONTENTS—Continued

Page

TRAINING AND EDUCATION

Interactive Training and Educational Development ...................................................... 36

Evaluation of Interactive Mine Safety and Health Training Methods ........................................ 37

Evaluating Toolbox Training for Construction and Mining ................................................ 38

Accident Reconstruction and Training for Metal/Nonmetal Mines .......................................... 39

Mine Rescue and Response ........................................................................ 40

Intervention Through Education and Training to Prevent Hearing Loss Among Miners ......................... 41

GROUND CONTROL

Safety Design for Underground Mine Stability ......................................................... 42

Reducing Ground Falls in Underground Stone and Nonmetal Mines ........................................ 43

Reducing Ground Fall Hazards in Nevada Underground Mines ............................................ 44

Identification and Control of Rock Burst Hazards ...................................................... 45

Slope Stability Hazard Recognition for Metal/Nonmetal Mines ............................................ 46

Development and Evaluation of Innovative Roof Support Technologies ..................................... 47

Coal Bump Reduction through Advanced Mine Design .................................................. 48

Ground Stability Assessment with Seismic Monitoring .................................................. 49

Design of Mine Ore Passes ........................................................................ 50

FIRES, EXPLOSIONS, AND VENTILATION

Control and Suppression of Mine Fires ............................................................... 51

Improving CFR Safety Evaluations for Mine Ventilation Seals and Stoppings ................................ 52

Hydrostatic Evaluation of Mine Seals ................................................................ 53

Characterization and Mitigation of Mine Gas Emissions ................................................. 54

Explosives Hazard Surveillance and Evaluation for the Mine Safety and Health Administration ................... 55

Explosion Hazards Reduction ...................................................................... 56

Extended-Cut Air Delivery Systems ................................................................. 57

Life Support for Survival and Rescue ................................................................ 58

Ventilation of Large-Opening Mines ................................................................. 59

Investigation of Flyrock Injuries and Fatalities ......................................................... 60

Lake Lynn Laboratory ............................................................................ 61

SURVEILLANCE

Hazard Surveillance in the Mining Industry ........................................................... 62

Improving Surveillance Data Utilization Through Geographical Information Systems ........................... 63

Risk Factors for Atherosclerosis Among Coal Miners ................................................... 64

Hazard Reduction in Surface Mining of Sand and Gravel ................................................. 65

A Health Hazards Study of Surface Drilling Operations .................................................. 66

EMERGING TECHNOLOGIES

Emerging Technologies and Other Issues in Mining ..................................................... 67

System Safety: Processor Control Applications ........................................................ 68
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 1

Artificial text fixture

(simulated human ear)

for hearing protector

research.

HEARING LOSS PREVENTION

INVESTIGATION OF TECHNOLOGY FOR

HEARING LOSS PREVENTION

RESEARCHER: David C. Byrne

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Noise, hearing

loss, hearing protectors, earplugs, earmuffs, communication

BIBLIOGRAPHY

Byrne DC, Driscoll DP [1998]. 

Acoustical considerations for

effective emergency alarm

systems in an industrial setting

(part 1). Milwaukee, WI:

Council for Accreditation in

Occupational Hearing

Conservation, Update 9(3).

Byrne DC, Driscoll DP [1998]. 

Acoustical considerations for

effective emergency alarm

systems in an industrial setting

(part 2). Milwaukee, WI:

Council for Accreditation in

Occupational Hearing

Conservation, Update 9(4).

Franks JR, Themann CL,

Sherris C [1994]. The NIOSH

compendium of hearing

protection devices. Cincinnati,

OH: U.S. Department of Health

and Human Services, Public

Health Service, Centers for

Disease Control and Prevention,

National Institute for

Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 95-105.

PURPOSE: Evaluate practical technological advances in hearing

protective devices for use in different mining environments.

RESEARCH SUMMARY: Previous NIOSH research shows that miners

develop hearing loss much more quickly than nonoccupationally noiseexposed individuals. Also, miners experience a greater severity of hearing

loss than would be expected for nonoccupational noise-exposed persons of

the same age and sex. As described in the National Occupational Research

Agenda, problems created by occupational hearing loss include (1) the reduced quality of life due to social isolation and unrelenting tinnitus, (2) impaired communication with family members, the public, and coworkers,

(3) a diminished ability to monitor the work environment (e.g., warning

signals, equipment sounds, etc.), (4) lost productivity and increased

accidents resulting from impaired communication and isolation, and 

(5) expenses for workers’ compensation and hearing aids.

Although the elimination of hazardous noise is the ideal long-term

solution to the noise problem, miners will likely need to rely on personal

hearing protection in certain situations for quite some time. However, it is

well known that noise attenuation provided by hearing protectors as they

are worn during everyday use in the workplace is usually worse than when

tested under laboratory conditions. Additionally, workers may refuse to

wear their hearing protection for any number of reasons. Therefore, this

project was initiated to evaluate practical technological advances in hearing

protectors, with an emphasis toward optimizing the balance between

effectiveness, comfort, overprotection, and communication ability.

Currently, the necessary in-house laboratory facilities and research

techniques are being finalized. Individual experiments are planned that

involve analysis of new hearing protector technology under both laboratory

and field conditions. The laboratory components are to consist of controlled studies using human subjects and/or an anthropometrically correct

artificial test fixture to evaluate the adequacy/effectiveness of various

hearing protective devices. Field studies are planned to determine the

actual usefulness and practicality of the hearing protectors as used in diferent mining environments. Recommendations can then be offered to the

mining community regarding correct earplug/earmuff usage that maximizes

recognition of hazard/warning sounds while adequately protecting the

miners’ hearing.
Spokane and Pittsburgh Research Laboratories

2 Office for Mine Safety and Health Research

Noise profiling of underground mining equipment.

CROSS-SECTIONAL SURVEY: NOISE 

EXPOSURE PATTERNS/SOURCES

RESEARCHER: Eric R. Bauer

AFFILIATION: Pittsburgh Research Laboratory

National Institute for

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Hearing loss,

research, exposure assessment,

noise exposure

BIBLIOGRAPHY

Bartholomae RC, Burks JA

[1995]. Occupational noise

exposures in underground

longwall coal mines. In:

Proceedings of Inter-Noise ‘95

(Newport Beach, CA), pp. 833-

836.

Bauer ER, Kohler JL [2000]. 

Cross-sectional survey of noise

exposure in the mining industry. 

In: Proceedings of the 31st

Annual Institute on Mining

Health, Safety and Research

(Roanoke, VA, August 27-30,

2000).

 

PURPOSE: Establish representative noise exposure

profiles of various mining occupations and equipment.

RESEARCH SUMMARY: In the mining industry,

overexposure to noise remains a serious problem for U.S. workers. Every

day, 80% of the Nation’s miners go to work in an environment where timeweighted average (TWA) noise levels exceed 85 dBA. Moreover, 25% of

the miners are exposed to a TWA noise level that exceeds 90 dBA. 

Research is needed to identify mine worker dosages and characterize the

noisiest equipment and worker activities. This will help ensure that the

hearing of miners is preserved, future hearing loss is prevented, and the

quality of life of our Nation’s miners will be enhanced.

The collection of baseline information provides a current and systematic

characterization of worker noise exposure patterns and mining noise

sources. This research is essential to develop effective intervention

strategies targeting engineering controls for noisy equipment and hearing

protection practices.

The approach of this research is to conduct a cross-sectional field study

of the noise exposure of mine workers. The study is to include a variety of

mine types, mining methods, equipment, geographic locations, and mine

sizes. Representative noise exposure profiles for the various mine worker

occupations will be established by undertaking comprehensive and extensive

noise exposure measurements using time-resolved dosimeters to obtain fullshift noise exposures. In addition, a profile of the noise levels of the various

mining machines is to be obtained using handheld sound level meters.

To date, noise measurements have been made at several underground

coal mines, a surface coal mine, a coal preparation plant, and a stone mine. 

Numerous other mine surveys are planned in the near future.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 3

Researchers conduct hearing computerized audiometric

evaluations. 

A MODEL HEARING CONSERVATION

PROGRAM FOR COAL MINERS

RESEARCHER: David C. Byrne

AFFILIATION: Pittsburgh Research Laboratory 

 National Institute for

 Occupational Safety and Health

 (412) 386-6683

KEYWORDS: Noise, hearing

conservation, hearing loss

prevention

BIBLIOGRAPHY

NIOSH [1998]. Criteria for a

recommended standard:

occupational noise exposure,

revised criteria 1998. 

Cincinnati, OH: U.S. Department of Health and Human

Services, Public Health Service,

Centers for Disease Control and

Prevention, National Institute

for Occupational Safety and

Health, DHHS (NIOSH)

Publication No. 98-126.

PURPOSE: Design a model hearing conservation program

for coal miners that includes both traditional and novel

approaches toward hearing loss prevention.

RESEARCH SUMMARY: Hearing loss is one of the 21 priority research

areas in the National Occupational Research Agenda and is a major

occupational health problem for coal miners. The prevalence of noiseinduced hearing loss (NIHL) has remained relatively unchanged for the

last 20 years. A significant reason for this is the lack of a systematic plan

of intervention proven to be effective for the mining community.

A cooperative agreement project was initiated with The Pennsylvania

State University to develop and implement a “model” hearing conservation

program (HCP) at a working underground coal mine. The objectives are to

design a model HCP that incorporates the best practices of well-run

programs from other industries, implement this program at a cooperating

mine, evaluate the program over a 5-year period to demonstrate its efficacy

in preventing hearing loss, and transfer findings to the coal mining industry

(and others) as quickly and thoroughly as possible.

Other specific goals of the project are to evaluate, document, and

statistically analyze hearing threshold shifts to quantify the program’s

effectiveness; determine individual worker and group data relative to selfreported perception of hearing handicap; identify the relationship between

NIHL and hearing threshold shifts; determine the most effective hearing

protection devices by measuring the amount of sound attenuation provided

for each individual miner; and explore the practicality of using inexpensive

personal noise monitors for alerting miners to the presence of excessive

noise levels.

A detailed 5-year plan for each program element was completed during

the previous year; databases were created to analyze audiometric test

results, noise exposure measurements, and other information. Hearing tests

are to be conducted every April and November for the duration of the

project. As this project begins its third year, attention is focusing on the

evaluation of personal hearing protection and the development and testing of

effective health education training materials and delivery methods.
Spokane and Pittsburgh Research Laboratories

4 Office for Mine Safety and Health Research

Noise profile for a continuous miner in free field, with the

cutter and conveyor running.

ENGINEERING CONTROLS FOR HEARING

LOSS PREVENTION

RESEARCHER: Peter G. Kovalchik

AFFILIATION: Pittsburgh Research Laboratory

National Institute for

Occupational Safety and Health

(412) 386-6648

KEYWORDS: Noise, control

technology, mining, equipment

BIBLIOGRAPHY

Bartholomae RC, Parker RP

[1983]. Mining machinery noise

control guidelines. Pittsburgh,

PA: U.S. Department of the

Interior, Bureau of Mines,

Handbook 2-83.

PURPOSE: Develop a strategy and implementation plan

for utilization of noise controls in mining to reduce noiseinduced hearing loss (NIHL) among mine workers.

RESEARCH SUMMARY: Overexposure to noise remains a widespread,

serious health hazard in U.S. mining and other industries despite 25 years of

regulation. Most other categories of illnesses and injuries associated with

mining have improved, except for hearing loss. The use of heavy

equipment, the drilling of rock, and the confined work environment are just

a few factors that contribute to high levels of noise exposure in mining. 

A recent NIOSH analysis of a large sample of audiograms showed that by

age 51 about 90% of coal miners and 49% of metal/nonmetal miners had a

hearing impairment. By contrast, only 10% of the nonoccupational noiseexposed population had a hearing impairment by age 51. Simply stated,

most miners have a hearing loss by the time they retire. While NIHL is the

most common occupational disease in this country, this problem is especially

acute among miners. This project focuses on targeting engineering noise

control for mining as the first line of defense.

Past research on engineering noise control has been reviewed to

determine what has been done and which mining machines are the major

sources of noise. Sound pressure profiles are being developed for these

mining machines in free field conditions. These sound pressure profiles are

being used to determine sound power sources of each machine. 

Theoretical models of sound pressure profiles are then to be derived for

differing mining conditions, which will be validated by in-mine

measurements.

Partnerships have been established with JOY, Kennametal, Fletcher,

and Consol, which are assisting in evaluating the strengths and weaknesses

of various implementation strategies. The strategies form the basis of a

long-term implementation plan where appropriate engineering controls are

to be selected and targeted to reduce excessive noise exposures to

workers.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 5

A Rock Buster is used to remove a roof fall.

INVESTIGATION OF IMPULSE NOISE

IN MINING

RESEARCHERS: Alex C. Smith and 

 Michael J. Sapko

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Mining,

exposure, intense sounds,

impulse

BIBLIOGRAPHY

Kuroda E, Kobayashi N [1982]. 

Studies on methods for

measuring blast noise: part 2. 

J Indus Explosives Soc (Japan)

43(4):233-238.

Kuroda E, Yoshida T, Ito S,

Kobayashi N [1982]. Studies on

methods for measuring blast

noise: part 1. J Indus Explosives

Soc (Japan) 43(4):225-232.

PURPOSE: Determine the extent of the hearing loss

hazard from intense noise sources and develop the basic

knowledge required to reduce the hazard through effective

control technology and training.

RESEARCH SUMMARY: Impulse noise sources exist

throughout the mining and construction industries and, to a lesser extent, in

agriculture and manufacturing. These sources are varied and range from

explosives to pile drivers. There are insufficient data to quantify the extent

of the resultant health problem or even to support the development of

damage risk criteria for impulse noises in confined areas. The most readily

available information consists of military data on peak pressure levels

associated with unconfined surface detonations as a function of distance

and charge mass. There are very little data on blasting in underground

complexes, e.g., tunnels and mines. The impulse noise from blasting in an

underground mine differs from that on the surface and is strongly influenced

by mine geometry, openings, and wall roughness. In a mine entry, the peak

intensity is higher at a given distance than for the same explosive mass

detonated on the surface, with the added complication that significant lowfrequency acoustic oscillations remain for several seconds after the passage

of the pioneer pressure pulse. The cumulative effect on workers associated

with impulse noise exposure of low frequencies remains unclear, although

considerable anecdotal evidence suggests that the effect is pronounced.

Research is underway at Lake Lynn Laboratory and the Safety

Research Coal Mine to measure pressure histories from the unconfined

detonation of the Mine Safety and Health Administration-approved

permissible “Rock Buster.” The initial focus of this new exploratory study

is intended to address the following: (1) Is the current practice of keeping

the blasting team at two right angles from the detonation sufficient to

prevent hearing damage? (2) Do audiometric models, such as that

developed by Dr. G. Richard Price, U.S. Army, Aberdeen Proving Ground,

correctly predict the risk and damage criteria associated with impulse noise

in the mining industry? Close collaboration with the U.S. Army Research

Laboratory and the mining industry is to continue in FY01.
Spokane and Pittsburgh Research Laboratories

6 Office for Mine Safety and Health Research

Wearing hearing protection for 85- to 90-dBA noise levels

is an element of the new noise rules promulgated by

MSHA.

EVALUATING THE ROLE OF POSITIVE

AND NEGATIVE EMOTION IN PROMOTING

HEARING CONSERVATION BEHAVIORS

AMONG COAL MINERS

RESEARCHER: Charles Vaught, Ph.D.

AFFILIATION: Pittsburgh Research Laboratory

National Institute for

Occupational Safety and Health

(412) 386-6648

KEYWORDS: Mining, hearing

loss, communication research

 

PURPOSE: To test the notion that positive emotions and

humor are as effective at motivating behavior change (such

as the wearing of hearing protection) as negative emotions,

or “fear messages.”

RESEARCH SUMMARY: Following a study of 17,260 audiograms from

2,871 coal miners, NIOSH concluded that 90% of coal miners have a

hearing impairment by age 51 compared with only 10% of the general

population. The present hearing conservation research will investigate two

strategies designed to increase hearing loss prevention behaviors among

coal miners. A communication framework for studying emotion in behavior

change, the Extended Parallel Processing Model (EPPM), has been

developed and validated in a number of occupational settings. It will be

used to assess the comparative effectiveness of humor versus fear in

motivating coal miners to adopt hearing loss prevention behaviors.

This research is timely because of new Mine Safety and Health

Administration (MSHA) noise standards in effect as of September 2000. 

The new plan has a number of voluntary behaviors associated with it,

including the wearing of hearing protection at noise levels between 85 and

90 dBA. Materials have been developed to explain key provisions of the

new standards and to list steps that miners can take to lessen the effects of

noise to which they may be exposed. The principles of message

development, design, and implementation used in this study can also be

applied to other occupational groups and risks.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 7

Two versions of the person-wearable dust monitor. The

left contains a lapel sampler and belt pack; the right has

an integrated cap lamp and dust sampler.

DUST MEASUREMENT AND

CONTROL

ASSESSMENT OF PERSONAL

PARTICULATE EXPOSURE

RESEARCHER: Jon C. Volkwein

AFFILIATION: Pittsburgh Research Laboratory

National Institute for

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Dust, exposure

assessment, coal mining, dust

sampling, black lung

BIBLIOGRAPHY

Page SJ, Volkwein JC, Baron

PA, Deye GJ [2000]. 

Particulate penetration of

porous foam used as a low flow

rate respirable dust size

classifier. J Appl Occup Env

Hyg 15(7):561-568.

Volkwein JC, Kissell FN [1999]. 

Update on the development of

person-wearable dust monitors. 

In: Proceedings of the 30th

Annual Institute on Mine Safety

and Health (Salt Lake City, UT,

August 9-11, 1999).

Volkwein JC, Schoeneman AL,

Page SJ [2000]. Laboratory

evaluation of pressure

differential-based respirable

dust detector tube. J Appl

Occup Env Hyg 15(1):158-164.

PURPOSE: Develop person-wearable monitors to

measure respirable mine dusts and diesel particulate.

RESEARCH SUMMARY: Prolonged inhalation of

respirable coal mine dust can cause coal worker’s

pneumoconiosis (CWP). Between 1968 and 1990, CWP

caused the death of 55,467 U.S. coal miners. Accurate

measurement of respirable dust is crucial to successfully reducing dust

exposures and ending disease. In 1988, NIOSH recommended that diesel

exhaust be regarded as a potential occupational carcinogen. Reducing

workplace exposure to diesel exhaust would cut back cancer risks. 

To reduce disease caused by particulate, improved measurement of

respirable coal mine dust and airborne diesel particulate is needed. Realtime particulate monitoring can effectively locate areas where dust controls

are needed and determine how well they are working. The Coal Mine

Respirable Dust Task Group of the Mine Safety and Health Administration

recommended development of both fixed-site and portable continuous

respirable dust monitors. Specifically, there is a need to understand what

mine dust fraction can be attributed to diesel exhaust. However, methods to

measure the DPM levels in mining are still in development, and no real-time

methods are available.

For a compliance accuracy device, NIOSH is developing under

contract a person-wearable dust monitor using the tapered-element

operating principle. The oscillating tapered element is the heart of a

commercially available dust monitor used around the world to assess

combustion particulate and ambient air quality levels. For a low-cost dustmeasuring device, a differential pressure instrument is being used as a

surrogate for mass. This device uses a disposable sample tube and a small

pump to deposit mass onto a filter. The increase in pres-sure, caused by the

dust loading, shows the dust level. In addition, new commercial instruments

and new combinations of technologies are being tested. One is the

combination of size-selective sampling with differential pressure

measurement. This idea could form the basis for a near-real-time diesel

particulate monitor for mine use. Another such combination is the

integration of smoke detector technology with light-scattering technology. 

This could be a way to discriminate between coal mine dust and diesel

particulate. The combined detector/light-scattering approach uses an ion

trap technology and discrete forward light scattering to determine diesel and

dust levels respectively. Bench-scale results are very favorable.
Spokane and Pittsburgh Research Laboratories

8 Office for Mine Safety and Health Research

Dust sampling in a full-scale longwall gallery.

DUST CONTROL IN LONGWALL MINING

RESEARCHER: Jay F. Colinet

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Coal mine dust,

underground mining, control

technology

BIBLIOGRAPHY

 

Colinet JF [1999]. Respirable

dust control technology utilized

in underground coal mines in the

United States. In: Hebblewhite

BK, Galvin JM, Broome AJ,

eds. Proceedings of the Second

International Underground Coal

Conference (Sydney, Australia,

June 15-18, 1999), pp. 171-179.

Colinet JF, Listak JM [1999]. 

Reducing worker exposure to

respirable dust at longwall

mining operations. In:

Proceedings of the International

Conference on Control of Dust

Hazards in the Mining Industry

(Wis»a, Poland, October 5-7,

1999), chapter XI.

Jankowski RA, Colinet JF

[2000]. Update on faceventilation research for

improved longwall dust control. 

Min Eng 52(3):45-52.

Organiscak JA [2000]. 

Investigation of longwall face

ventilation air-splitting methods

for improved dust control. Trans

SME 306:86-94.

PURPOSE: Reduce the respirable dust exposure of mine

workers at longwall mining operations of underground coal

mines.

RESEARCH SUMMARY: Medical studies have shown

that long-term exposure to excessive levels of respirable

coal mine dust can lead to the development of coal workers’

pneumoconiosis (CWP), a debilitating lung disease commonly known as

“black lung.” The most recent results of a voluntary x-ray screening

program for underground coal mine workers indicates that about 8% of the

workers with 25 or more years of mining experience were diagnosed with

CWP. In 1999, shift production from longwall mining operations averaged

5,000 tons per shift; longwall mines accounted for over 50% of underground

coal production. Nearly one of every five compliance dust samples from

longwall operations exceeds the permissible exposure limit. Data from dust

sampling, medical screening, and production trends indicate that controlling

dust on longwalls remains a major health concern and challenge for longwall

mining.

This multitasked research project addresses improvements in the

application of primary control technologies: ventilating air and spray water. 

Laboratory testing is being conducted at a full-scale longwall gallery at the

Pittsburgh Research Laboratory to evaluate the interactions between

ventilating air, water flow, water pressure, spray system design, cutting

direction, and mining height to measure the impact on dust levels on the

longwall face. Tests at a mining height of 7 feet have been completed. The

data from these tests are currently being analyzed to identify dust control

trends that can be used by an individual longwall operator to optimize dust

control for conditions specific to that mine. Additional laboratory testing has

been completed within a wind tunnel designed to simulate dust liberation

during shield advance and subsequent entrainment in high-velocity

airstreams. Statistically significant increases in respirable dust levels were

observed as air velocity was increased from 400 to 1,600 feet per minute.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 9

Inlet hood prototype for improved

dust capture on drilling operations.

DUST CONTROL IN SURFACE COAL MINING

RESEARCHER: Jeffrey M. Listak

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Surface mining,

respirable dust, drilling, silica,

dust control technology

BIBLIOGRAPHY

 

NIOSH [1998]. Hazard

Controls 27: new shroud design

controls silica dust from surface

mine and construction blast hole

drills. Cincinnati, OH: U.S.

Department of Health and

Human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute for

Occupational Safety and Health,

HC27, DHHS (NIOSH)

Publication No. 98-150.

Organiscak JA, Page SJ [1999]. 

Field assessment of control

techniques and long-term dust

variability for surface coal mine

rock drills and bulldozers. Int J

Surf Min Reclam Env 13(4):

165-172.

Organiscak JA, Cecala AB,

Heitbrink WA, Thimons ED,

Schmitz M, Ahrenholtz E

[2000]. Field assessment of

retrofitting surface coal mine

equipment cabs with air

filtration systems. In:

Proceedings of the 31st Annual

Institute on Mining Health,

Safety and Research (Roanoke,

VA, August 27-30, 2000).

PURPOSE: Identify the effectiveness of existing dust

control technologies used for highwall rock drills and

bulldozers at surface coal mining operations and improve

coal miners’ health protection from silica dust exposure

through the advancement of control technologies.

 RESEARCH SUMMARY: Silicosis is a well-known

 occupational disease that kills more than 200 people annually

 and cuts across a wide variety of industrial settings. Surface

mine rock drillers in particular are at high risk because of the potential of

being exposed to extremely high levels of respirable silica dust when drilling

through rock containing silica. NIOSH conducted a study of job categories

to examine exposure data collected during a 2-year period at surface mine

sites, preparation plants, and shop/maintenance facilities. The study

concluded that the highwall drill operator and helper had the two highest

silica exposures of all job categories examined.

The interactions between drilling parameters and overburden lithology

are being characterized to determine how these interactions affect

respirable silica dust generation. Once the drilling parameters and rock

characteristics have been defined in terms of their impact on silica dust

generation, appropriate control technologies can be developed to reduce

silica emissions. Furthermore, many surface drills have dust containment

problems at the shrouded drill table over the hole. Preliminary testing of an

impaction inlet hood prototype of the drill’s primary dust collection system

was conducted and has shown that the new design successfully deflected

larger size particles from being drawn into the collector. During surface

mine dust surveys, sampling was also done to identify silica sources,

exposures, and controls for bulldozer operators. Investigations into

improving quality control methods to ensure the integrity of enclosed

environmental cabs on bulldozers are being done through cooperative work

with mining companies, equipment manufacturers, and the Mine Safety and

Health Administration. A Cooperative Research and Development

Agreement (CRADA) was drafted with Clean Air Filter to develop field

test methods for evaluating the environmental integrity of enclosed operator

cabs.
Spokane and Pittsburgh Research Laboratories

10 Office for Mine Safety and Health Research

Cooperative research effort to lower surface drill operator

silica dust exposure by improving cab filtration efficiency

and pressurization.

SILICA DUST CONTROL IN METAL/

NONMETAL SURFACE MINING

RESEARCHERS: Andrew B. Cecala and 

 Gregory J. Chekan

AFFILIATION: Pittsburgh Research Laboratory

National Institute for

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Silicosis, silica

dust, control technology,

underground mining, surface

mining, mineral processing

BIBLIOGRAPHY

Cecala AB, Timko RJ, Zimmer

JA, Thimons ED [2000]. 

Respirable dust evaluation of

two portland cement operations:

part 1. Cement Americas

Jan/Feb:20-23.

Cecala AB, Timko RJ, Zimmer

JA, Thimons ED [2000]. 

Respirable dust evaluation of

two portland cement operations:

part 2. Cement Americas

Mar:28-30.

Cecala AB, Zimmer JA, 

Smith B, Viles S [2000]. 

Improved dust control for bag

handlers. Rock Prod 103(4):46-

49.

PURPOSE: Develop control technology to reduce worker

exposure to silica and other harmful contaminants in

metal/nonmetal mining operations.

RESEARCH SUMMARY: Although all types of respirable dust are

potentially harmful to a worker’s lungs, overexposure to respirable silica is

extremely hazardous. Chronic overexposure to respirable crystalline silica

(particle diameter <10 microns) leads to progressive lung deterioration

known as silicosis. In addition, in 1997, the International Agency for

Research on Cancer stated that silica dust is also carcinogenic (lungs). 

More than 1 million workers across the United States are exposed to silica

dust each year.

The Mine Safety and Health Administration’s (MSHA) records indicate

that there is a significant percentage of both underground and surface

metal/nonmetal miners overexposed to silica each year. The following

occupations have the highest exposures: truck drivers, crusher operators,

front-end loader operators, rotary drill operators, bag operators, bag

stackers, laborers, maintenance, cleanup, and utility workers.

One research effort is underway to determine the impact of different

plant structural designs on respirable dust concentrations. This study has

shown that, as expected, an open structure design provided the lowest dust

levels of the various structures evaluated.

An extensive research effort is ongoing to lower equipment operators’

dust exposure by improving filtration efficiency and pressurization in

enclosed cabs in all types of mining equipment. This research is a

multifaceted effort being performed in cooperative agreement with MSHA,

several mining companies, and a number of dust filtration and pressurization

manufacturers. Evaluations are currently being done at two surface mining

operations. An enclosed cab study is also being investigated for a loadhaul-dump application in an underground gold mine.

Research is also currently being conducted at both underground

limestone and gold mines to determine primary silica dust sources and

evaluate control technology. Improvements in mine-wide ventilation and

localized ventilation systems are being investigated as a primary means for

controlling various dust sources in underground operations.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 11

Roof bolter dust collectors require regular cleaning of the

dust box and canister filter.

CONTROL OF SILICA DUST EXPOSURES IN

UNDERGROUND COAL MINING

RESEARCHER: Gerrit V. R. Goodman, Ph.D.

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Silica exposures, dust, coal mining,

ventilation

BIBLIOGRAPHY

Goodman GVR [2000]. Using

water sprays to improve

performance of a flooded-bed

dust scrubber. J Appl Occup

Env Hyg 15(7):550-560.

Goodman GVR, Listak JM

[1999]. Variation in dust levels

with continuous miner position. 

Min Eng 51(2):53-58.

PURPOSE: Develop means of reducing exposures to

respirable silica dust at the continuous mining machine and

roof bolter operator’s location.

RESEARCH SUMMARY: The Federal respirable dust standard limits

exposures to 2.0 mg/m3 for an 8-hour working shift. If the silica content

exceeds 5% by weight, the dust standard is reduced to 10/(% silica). The

2.0 mg/m3 standard and a reduced standard limit silica exposures to

100 μg/m3. However, recent data from the Mine Safety and Health

Administration show that about one-fourth of continuous mining machine

and roof bolter operator samples exceed 100 μg/m3.

In-mine surveys indicate that overexposures to respirable silica dust can

occur when the roof bolting machine works downwind of the continuous

mining machine. A canopy air curtain, mounted on the underside of the

roof bolter operator’s canopy, can reduce these exposures by providing a

constant flow of filtered air over the roof bolter operator. Laboratory tests

were completed that show that the air curtain provides dust reductions for

positions close to the canopy, although these reductions decrease as mean

entry air velocity increases. In-mine evaluations of the canopy air curtain

system are planned.

These mine surveys also show that the roof bolter can be a source of

silica dust exposure for the continuous mining machine operator. Although

existing dust collection systems on roof bolters can be very effective when

operating properly, a lack of regular maintenance can reduce their

effectiveness. Specifically, the dust canister filters can become clogged

through lack of cleaning or torn through improper cleaning. Laboratory

research is to be conducted to measure filter integrity and efficiency with

regard to the impact of multiples cycles of filter loading and cleaning. 

Guidelines can be presented regarding proper use and maintenance of dust

filters.

Water sprays and ventilation airflow are used to control dust exposures

and methane gas levels. However, specific applications of water and

ventilation to control respirable dust may not always control gas levels

effectively. Using a full-scale test facility in conjunction with state-of-the

art gas monitoring equipment, testing is to be done to evaluate different

water spray and ventilation airflow designs for effective control of both

respirable dust and methane gas.
Spokane and Pittsburgh Research Laboratories

12 Office for Mine Safety and Health Research

A water-powered scrubber simultaneously entrains air

movement and captures dust.

DEVELOPMENT OF ENHANCED SPRAY

DUST CAPTURE PRINCIPLES FOR

IMPROVED SILICA DUST SUPPRESSION

RESEARCHER: John A. Organiscak

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Respirable

crystalline silica dust, mining,

spray dust capture

PURPOSE: Develop several novel spray nozzle

technologies and apply fluid dynamic principles to improve

water droplet collection efficiency of airborne respirable

silica dust.

RESEARCH SUMMARY: Overexposure to airborne respirable

crystalline silica dust can cause serious or fatal respiratory disease. Mining

machine operators were the most frequent occupation (16.0%) recorded on

silicosis-related death certificates during 1991-92; coal mining was the first

(9.5%) and metal mining was the third (8.6%) most frequent associated

industry. Compliance data from the Mine Safety and Health Administration

(MSHA) for the permissible exposure limits (PELs) indicate that nearly

25% of the coal mine dust samples and over 20% of the metal mine dust

samples exceed the MSHA-mandated PELs. About one-eighth of the

nonmetal and stone mines also exceed their mandated respirable dust PELs. 

These data indicate that there continues to be a high likelihood of

overexposure to silica dust in the mining industry, especially in coal and

metal mines, which have a high incidence of silicosis deaths.

The approach taken to combat the amount of respirable silica dust

exposure present in the mining industry is to develop several enhanced

spray dust capture principles into mine functional engineering control

systems. This enhanced spray dust capture research will focus on

increasing the probability of water droplet and respirable-dust particle

interaction by (1) increasing the number of smaller sized spray droplets per

unit volume of water used and (2) optimizing the energy transfer of spray

droplets with the dust-laden air.

Spray atomization literature from other industries (automotive,

aerospace, process engineering, agriculture, and medical) is being studied

for application to experimental design and physical modeling of spray

system optimization for dust capture.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 13

Many miners are exposed to high levels of DPM.

DIESEL EMISSIONS AND

TOXIC SUBSTANCES

REDUCING DIESEL PARTICULATE

EXPOSURE IN WESTERN MINES

RESEARCHER: Art Miller

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

(503) 354-8000

KEYWORDS: Diesel

exhaust, diesel particulate

matter, worker exposure,

mine health and safety,

hydrogen

BIBLIOGRAPHY

Miller A [1999]. Health

and safety of diesel

emissions. Presentation at

Northwest Mining

Association conference

(Spokane, WA, November

30).

Miller A [2000]. Diesels:

clean energy for the future. 

Presentation at Alaska

Governor’s Health and

Safety Conference

(Anchorage, AK, March

20).

PURPOSE: Reduce the exposure of workers in western mines to

potentially dangerous levels of exhaust from diesel engines. Products of

this research will be information and tools that the mining industry can use

to reduce worker exposure levels.

RESEARCH SUMMARY: Exposure to diesel exhaust, especially diesel

particulate matter (DPM), has been recognized as a health concern for

some time. The Mine Safety and Health Administration has identified DPM

as a potential hazard and anticipates putting new regulations in place to help

reduce worker exposure in underground mines. Several entities, including

the U.S. Environmental Protection Agency, have produced studies that

suggest diesel exhaust should be labeled as carcinogenic. As these events

have unfolded, and despite uncertainties about current and past exposures

of miners and health effects, key mining stakeholders have come together

to pursue the reduction of diesel emissions in the mining workplace through

partnerships. This project will support western mining partnerships through

control technology research applied to existing diesel equipment and through

feasibility studies of zero emissions technologies that could replace diesel

engines.

A fully successful program has the potential to reduce exposure to

diesel particulates by 90% or more. If implemented in underground mines,

almost 100,000 workers would see significant reduction in DPM exposures. 

Research results could also be applied in other industrial sectors where

diesel engines are used in close quarters, i.e., factories and warehouses. 

The transfer of technology to these sectors could reduce exposure for

hundreds of thousands of employees in nonmining industries.
Spokane and Pittsburgh Research Laboratories

14 Office for Mine Safety and Health Research

Research scientists, using the thermo-optical method

(NIOSH method 5040 for carbon) to determine the

amount of DPM on filter samples collected in the

workplace, are able to assess worker exposure and

effectiveness of emission control systems.

DIESEL ENGINE EMISSIONS MEASUREMENT AND ANALYSIS

RESEARCHER: Bruce K. Cantrell, Ph.D.

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Underground

mining, diesel, exhaust, soot,

elemental carbon, measurement

BIBLIOGRAPHY

Cantrell BK, Watts WF Jr.

[1997]. Diesel exhaust aerosol:

review of occupational

exposure. J Appl Occup Env

Hyg 12(12):1019-1027.

McDonald JF, Cantrell BK,

Watts WF Jr., Bickel KL

[1997]. Evaluation of a soybean

oil based diesel fuel in an

underground gold mine. CIM

Bulletin 90(1015):91-95.

PURPOSE: Advance technology for measurement of

worker exposure to diesel exhaust contaminants in

underground mines.

RESEARCH SUMMARY: Various State, Federal, and

private health-watch organizations have declared diesel particulate matter

(DPM), or carbon-based soot, to be a suspected or probable carcinogen. 

Recently, one nongovernment body, responsible for recommending

occupational exposure guidelines, recommended a DPM concentration limit

of 50 :g/m3. DPM levels in U.S. mines expose about 30,000 workers to

concentrations that approach 20 times this limit.

This project directly addresses the issue of accurately measuring DPM

in the presence of carbon-containing mine aerosols (coal, limestone, and

other ore dusts), oil mists, and cigarette smoke. In its proposed rule to

regulate workplace concentrations of DPM in underground metal and

nonmetal mines, the Mine Safety and Health Administration selected an

analytical method that is susceptible to measuring the aforementioned

carbon-containing mine dusts along with the diesel DPM. NIOSH performs

laboratory and field experiments to define and mitigate the effects of

nondiesel dusts on the measurement of DPM.

In underground mines with airborne ore dusts and elevated DPM levels,

ore samples are being gathered. After technicians pulverize these ore

samples to dust, they mix the dust with diesel exhaust and inject the mixture

into a laboratory chamber. Dust samples are collected from within the

chamber, and the results are analyzed. The goal is to quantify the effects of

the carbon-based dusts on the compliance method and, ideally, to develop

methods to stop these effects.

Accurate DPM measurement can reduce uncertainties concerning

workplace concentrations of DPM, which enables better assessment of the

effects of control technology on tailpipe emissions. It also provides a better

measurement of worker exposures and workplace DPM concentrations.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 15

A small (4-ton) fuel cell-powered mine locomotive.

(Courtesy of R. A. Warren Equipment, North Bay, Ontario,

Canada).

SAFETY AND HEALTH EVALUATION

OF A FUEL CELL-POWERED FOUR-TON

LOCOMOTIVE FOR UNDERGROUND MINING

RESEARCHER: James C. Cawley

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

(412) 386-6648

KEYWORDS: Mining, fuel

cell, diesel, particulate, noise,

locomotive

PURPOSE: Investigate the anticipated air-quality improvements and

workplace noise level improvements expected when implementing fuel cellpowered mining vehicle technology to supplement diesel vehicle technology

in underground mines.

RESEARCH SUMMARY: Due largely to the efforts of the Fuel Cell

Propulsion Institute (FPI), fuel cell technology is anticipated to be

demonstrated in the mining industry in the near future in the form of a 4-ton

locomotive. Two areas are to be measured in field tests on a prototype

vehicle: (1) air-quality improvements and (2) the improvements expected in

workplace noise levels.

The Pittsburgh Research Laboratory has conducted a literature review

to determine the performance to be reasonably expected of fuel cell

technology in mining applications. The existing literature on diesel

technology and a knowledge of proton exchange membrane fuel cell

technology suggests that air-quality issues with a H2-powered fuel cell

vehicle will be nonexistent. Diesel exhaust contaminants will no longer

contaminate workplace atmospheres. The emissions from the fuel cell

powerplant will be water and oxygen-diminished air. Noise levels from fuel

cell-powered vehicles should be comparable to those from electric vehicles. 

The greatest concern is H2 safety, but contractual commitments by the FPI

member companies have precluded a detailed NIOSH examination of this

area of the technology.

The Mine Safety and Health Administration’s (MSHA) Approval and

Certification Center has sole authority and responsibility to grant or withhold

an approval. NIOSH’s role is to develop a protocol and conduct

measurements to document the performance of each class of vehicles. 

Successful completion of this project will yield the first documented tests of

the noise and air-quality performance of a fuel cell-powered mining vehicle.
Spokane and Pittsburgh Research Laboratories

16 Office for Mine Safety and Health Research

Diesel exhaust filtration on mining equipment offers substantial reductions in workplace DPM concentrations.

DIESEL PARTNERSHIP RESEARCH

RESEARCHER: George H. Schnakenberg, Jr., Ph.D.

AFFILIATION: Pittsburgh Research Laboratory

National Institute for

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Underground

mining, diesel, exhaust, soot,

exhaust controls

PURPOSE: Investigate and evaluate performance of

diesel exhaust control technology for application in

underground coal and metal/nonmetal mines, with particular

focus on technology for engines in outby areas of coal

mines.

RESEARCH SUMMARY: In many underground coal mines, mantrip

and utility vehicles are diesel-powered. This machinery adds significantly to

gaseous and particle contaminant levels in the ventilation air. Increasing the

quantity of these contaminants can have a negative effect on miner health. 

As a result, the Bituminous Coal Operators Association, the United Mine

Workers of America, and NIOSH have formed a partnership. The goal of

this alliance is to find and test practical methods of reducing diesel exhaust

contaminants. The partnership resulted in this project, which began in

January 2000.

More stringent air-quality standards for highway and off-highway

trucks are driving the rapid advances in diesel engine emission control

technology. NIOSH researchers investigated these advancements and

generated a summary of the many technology documents. Based on this

assessment, in-mine evaluations of alternative emission control technologies

are planned.

The Pittsburgh Research Laboratory is to soon receive a transportable

engine dynamometer. This device will enable testing of emission control

technologies at operating mines. At these locations, engine loads and mine

ventilation dilution conditions can be realistically controlled. Plans also call

for the long-term field testing of promising exhaust aftertreatment systems

on mantrip vehicles at a partner’s mine. Implementation of these control

technologies can reduce emitted diesel particulate matter (DPM) by 95%. 

In addition, mines will have available cleaner engines and enhanced control

systems. When miners apply these solutions and make use of better

maintenance, they can effectively reduce worker DPM exposures.

Consult www.deep.org and www.dieselnet.com for up-to-date reports

of research in the area of diesel emission control technology.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 17

A sampling pump is being placed

near the main rock crusher in a mill

to collect a dust sample.

PORTABLE MONITORS FOR AIRBORNE

METALS AT MINING SITES

RESEARCHER: Pamela L. Drake

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Mining,

exposure assessment,

engineering controls

PURPOSE: Develop field-portable technologies and

methods to (1) determine airborne metal concentrations in

mines and refining operations rapidly so potential

overexposures can be assessed quickly and (2) implement

and evaluate intervention controls on a timely basis.

RESEARCH SUMMARY: Most workers at mining and

construction sites encounter dust and fumes throughout the

workday. In some cases, metals and trace amounts of other

toxic substances in these dusts and fumes can cause

 significant health effects if exposures are great enough. 

Concern with metal exposures at construction and mining sites has been

increasing as more connections between exposures and health effects are

made. Identifying toxic substances in dust is a goal for all mining

commodities. Previously, it was not possible to obtain timely on-site

analyses of metal concentration and exposure data due to the lack of fieldportable devices that were cost-effective and practical.

At present, the most common method of assessing workers’ exposures

to multiple airborne metals involves collecting filter samples and sending

them to an analytical laboratory. There, wet chemistry methods are used to

pretreat the sample, usually by digesting the filter medium. However, the

time delay associated with this procedure has made it difficult to study realtime exposure. Therefore, in determining whether workplace metal

exposures should be reduced and to evaluate subsequent control strategies,

NIOSH researchers are utilizing cost-effective, on-site screening

techniques for assessing multiple metal concentrations with near real-time

(end-of-shift) speed.

On-site exposure assessment studies for lead are being conducted. 

Sampling consists of 2 days of collecting area air samples during milling and

smelting operations in accordance with NIOSH standard methods. The

samples are then analyzed for lead with field-portable x-ray fluorescence

(XRF) spectrometry and anodic stripping voltametry (ASV) equipment. 

Preliminary results are given to the mining companies within a few days of

sample collection. The samples are then sent to a laboratory for verification

by standard analytical methods. Two to three months may pass before

these results are received.

This new project will demonstrate the capability of the instrument and

methods to measure and analyze the different forms of lead found in mining

and smelting operations accurately. The benefit to the mining operation is

near-real-time reporting of results.
Spokane and Pittsburgh Research Laboratories

18 Office for Mine Safety and Health Research

Following the processing of gold ore, a refinery worker in

Bella Rica, Equador, burns the remaining impurities,

which may lude small amounts of mercury.

CHEMICAL HAZARDS IN MINING AND

PROCESSING

RESEARCHER: Pamela L. Drake and Patrick Hintz

AFFILIATION: Spokane Research Laboratory 

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Mercury,

silver, mining, exposure

assessment

BIBLIOGRAPHY

Drake PL, Jenkins FM, Reh

CM, Rojas M [1999]. 

Assessing occupational exposure to mercury in El Callao,

Venezuela. Presentation at the

Fifth International Conference

on Mercury as a Global

Pollutant (Rio de Janeiro, Brazil,

May 23-28).

PURPOSE: Investigate and evaluate potential chemical

hazards in mining workplaces to enable development of

control or mitigation methods. Characterize exposure to

mercury vapor, silver dust and fumes, and hydrocarbons in

underground coal mines.

RESEARCH SUMMARY: Exposure to metals and other chemicals in

mining workplaces, particularly in milling and refining facilities, may

adversely affect thousands of workers. Mercury occurs naturally in some

ore deposits, and because of its similarity to gold and silver in chemical

complexing and adsorption behavior, it is retained during processing. 

Because mercury has a high vapor pressure, whenever ore concentrates

containing mercury are heated, the mercury is vaporized. While the use of

mercury for processing gold is illegal in the United States, it is still used

extensively in developing countries and continues to introduce both

environmental and health risks worldwide. Minimizing exposure to mercury

is crucial due to the serious health effects associated with overexposure. 

NIOSH researchers conducted surveys to determine if overexposure to

mercury was occurring in Venezuela and Ecuador. Included in the surveys

were industrial hygiene studies, biological monitoring, and an evaluation of

mining processes.

Overexposure to the soluble form of silver also presents a potential

hazard. The soluble compounds of silver are considered to be more toxic

than silver metal dust and fumes; therefore, the American Conference of

Governmental Industrial Hygienists (ACGIH) established separate threshold

limit values (TLV) for metallic and soluble compounds of silver. However,

the Mine Safety and Health Administration, NIOSH, and the Occupational

Safety and Health Administration do not use separate standards. Research

is being conducted to develop an analytical method that will differentiate

between water-soluble silver compounds and metallic silver. This will

enable mining companies to focus engineering control efforts on areas with

higher concentrations of soluble silver compounds.

Some underground coal mines have encountered pockets of naturally

occurring liquefied hydrocarbons. The purpose of this aspect of the project

is to characterize the hydrocarbon material, determine the toxicity and the

potential health hazard from dermal and inhalation exposures, compare the

results to the established occupational exposure limits, and determine the

flammability of the material and how the hydrocarbons will affect the lower

explosive limit in the mine.

The engineering controls used by participating mines to minimize

exposures will be evaluated. Additional workplace evaluations at precious

metal mines will be conducted to collect information about mercury and

silver exposure hazards.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 19

NO2 fumes after a blast.

TOXIC FUMES FROM BLASTING

RESEARCHER: James H. Rowland III

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Explosives,

blasting agents, fumes

BIBLIOGRAPHY

Mainiero RJ [1997]. A

technique for measuring toxic

gases produced by blasting

agents. In: Proceedings of the

23rd Annual Conference on

Explosives and Blasting

Technique. Cleveland, OH:

International Society of

Explosives Engineers, pp. 595-

604.

PURPOSE: Reduce worker exposure to blasting fumes

by determining the causes of excessive blasting fumes and

the toxic fumes generation of various blasting agents under

different blasting conditions. Develop strategies to

minimize exposure to the fumes.

RESEARCH SUMMARY: All explosives generate toxic fumes when

detonated. The composition of these fumes is typical of what might be

expected from any combustion process and includes carbon monoxide

(CO), nitric oxide (NO), nitrogen dioxide (NO2), and ammonia (NH3). Care

must be taken to ensure that workers are protected from the fumes. As

mines have switched from high explosives to ammonium nitrate/fuel oil

(ANFO) over the past 30 years and blasts have increased in size, the

problem of toxic fumes generation in blasting has increased.

To address the hazards of toxic fumes, a chamber has been constructed

in which up to 10 pounds of blasting agent may be detonated and the toxic

fumes confined. Following detonation, the fumes are sampled to determine

the quantities of CO, NO, NO2, NH3, and other toxic gases. Blasting agent

formulations typical of those employed in industry are evaluated to

determine their relative fumes generation. The blasting agent is loaded in

steel pipes of various wall thicknesses to simulate a variety of confinements. 

The blasting agent is soaked in water to simulate loading blasting agent in

wet boreholes. Additionally, a variety of contaminants may be added to the

blasting agent to determine their effect on fumes generation. Opportunities

to extend this research into the field through cooperative agreements with

mines are being explored.

This research is carried out in partnership with the Institute of Makers

of Explosives, its member companies, and the members of the Wyoming

Mining Association, all of which are aware of the hazard and are seeking

solutions.
Spokane and Pittsburgh Research Laboratories

20 Office for Mine Safety and Health Research

Mounting a collision warning device

on the rear end of a haulage truck.

HAZARD DETECTION AND 

WARNING DEVICES

SAFETY ENHANCEMENTS FOR OFFHIGHWAY HAULAGE TRUCKS

RESEARCHER: Todd Ruff

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Surface mining,

powered haulage, dump truck,

collision warning system,

proximity detection

BIBLIOGRAPHY

NIOSH [2000]. Technology

news 479: Ore pass level and

blockage locator device. 

Spokane, WA: U.S. Department

of Health and Human Services,

Public Health Service, Centers

for Disease Control and

Prevention, National Institute

for Occupational Safety and

Health.

Ruff TM [2000]. Collision

warning systems for surface

mining equipment. Presentation

at California Mine Safety and

Health Conference

(Sacramento, CA, March 9).

Ruff TM [2000]. Test results of

collision warning systems for

surface mining dump trucks. 

Spokane, WA: U.S. Department

of Health and Human Services,

Public Health Service, Centers

for Disease Control and Prevention, National Institute for

Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 2000-120, RI 9652.

PURPOSE: Develop interventions that will decrease

accidents involving off-road dump trucks in surface mining

 operations. Specific goals include reducing fatalities and

 injuries caused (1) when a truck operator cannot see all

areas around the equipment from the cab and (2) by a lack of operator

training or experience in adverse conditions.

RESEARCH SUMMARY: The following tasks are planned:

(1) Visibility aids for dump truck operators. This task will focus on

developing and testing systems that provide information to a truck driver

regarding the environment around the truck. The systems may consist of

several technologies for providing reliable information to prevent collisions

and other accidents, such as—

• Enhanced visual information from cameras on the truck that monitor blind

area.

• Sensory information that warns an operator that the truck is near an

obstacle, vehicle, person, or a change in terrain.

• Truck position and attitude data showing the distance to dumping points or

other hazardous locations.

(2) Improved truck driver training for adverse conditions. This task

will involve investigating available training methods and materials to

determine if improvements can be made in training curricula for truck

drivers. The focus will be on training a driver to react correctly in adverse

situations, such as mechanical failure, excessive speeds on steep haul roads,

adverse weather, and slippery roads. The future direction of this task will

depend on findings during the first year, but may include developing

improved training materials or methods and evaluating the latest training

simulator technology as it becomes available. Recommendations will be

made based on these evaluations.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 21

Static load/load rate monitoring system being tested on

an MRS in a western U.S. coal mine.

MOBILE MINING EQUIPMENT WARNING

SYSTEMS

RESEARCHERS: John Owens and Wayne Howie

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Mining, mobile

roof supports, pillar extraction,

warning system, rollover, control

technology

BIBLIOGRAPHY

Howie W, Owens J [1999]. 

Mobile roof support load rate

monitoring system. In:

Proceedings of the IEEE

Industry Applications Society

(Phoenix, AZ, October 3-7). 

Vol. 1, pp. 234-239.

Maleki H, Owens J [1999]. An

overview of geomechanics

safety research on mobile roof

supports. In: System Safety at

the Dawn of a New Millennium. 

Proceedings of the 17th

International System Safety

Conference (Orlando, FL,

August 16-21). Unionville, VA:

System Safety Society, 

pp. 554-563.

PURPOSE: Develop effective monitoring and warning

systems for mobile mining equipment to reduce accidents

resulting from dangerous operating conditions and

practices.

RESEARCH SUMMARY: A common danger in the mining industry

occurs when mobile mining equipment is unknowingly operated in unstable

configurations and dangerous conditions. Such instabilities can be initiated

through both operator error and changing terrain and can result in

equipment rollovers and deaths of workers. Unstable configurations and

poor operating practices most frequently occur during the operation of

front-end loaders, skid-steer loaders, highway trucks, and dozers. 

According to accident and fatality data for 1991-95 from the Mine Safety

and Health Administration, the second largest category of causes of

fatalities at underground mines was powered haulage (22%), while at

surface mines, the categories were powered haulage (42%) and machinery

(18%). A load rate monitoring device was developed by SRL researchers

for mobile roof support (MRS) machines. The device monitors the loading

rate on an MRS in real-time to alert miners of unstable ground conditions

during pillar-pulling operations. Lights on the device indicate progressively

higher load rates on the machine.

An integrated ground monitoring system is currently undergoing longterm testing at a coal mine in Utah. The system combines the simplicity of

convergence measurements with monitoring the load rate on the hydraulic

legs of an MRS to alert miners to unstable roof and pillar conditions so that

miners and equipment can be removed before a roof fall occurs. Following

successful completion of the field evaluation, the device will be adapted to

monitoring critical operating parameters of other mobile mining equipment.

The research is being performed in four phases. The first phase

involves completing the field tests and evaluations of the monitoring device

on an MRS in a retreat mining section. The second phase will involve

selecting mobile equipment to be studied according to criteria based on

protecting the greatest number of workers. The third phase will involve

identifying critical operating parameters that signify unsafe operating

practices for the equipment selected and appropriate sensors to monitor

these parameters. The fourth phase will involve redesigning the patented

microprocessor-based MRS warning system to monitor these critical

operating parameters and trigger an alarm whenever a critical combination

of these factors occurs.
Spokane and Pittsburgh Research Laboratories

22 Office for Mine Safety and Health Research

Warning device to alert miners to rock fall hazards.

ADVANCED WARNING OF GROUND

STABILITY HAZARDS

RESEARCHERS: Steve Signer and Lewis Martin

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Underground

mining, ground stability,

monitoring instruments 

BIBLIOGRAPHY

Martin L, Pakalnis R, Curtin R

[2000]. Field tests of cable bolts

using instrumented king wires. 

Presentation at CIM 2000

meeting (Toronto, Ontario,

Canada, March 5-10).

McHugh E, Signer S [1999]. 

Roof bolt response to shear

stress: Laboratory analysis. In:

Peng SS, Mark C, eds. In:

Proceedings of the 18th

International Conference on

Ground Control in Mining. 

Morgantown, WV: West

Virginia University, pp. 232-238.

PURPOSE: Investigate ongoing developments in

electronics, communications, and computer technologies;

identify appropriate safety applications for these advances;

and adapt and apply these improved technologies to

monitoring ground stability hazards in underground mines. 

In conjunction with this research, develop practical warning devices to alert

underground workers of hazardous locations and impending ground control

failures.

RESEARCH SUMMARY: Mine Safety and Health Administration

statistics indicate that there is a dire need to warn underground miners of

unexpected ground stability hazards. Although research studies conducted

by the former U.S. Bureau of Mines and NIOSH have demonstrated that

geotechnical instruments can be used effectively to identify and monitor

ground control hazards, modern rock mechanics instruments are rarely used

by the mining industry. Most mines, especially the smaller operations, do

not have the expertise or resources available to design an effective

instrumentation plan, properly install and monitor a variety of instruments,

and analyze and interpret the electronic readings obtained from the

instruments. As a result, ground control hazards are primarily monitored

through visual observations, and injuries and fatalities continue to occur

because of unexpected roof and rib falls.

To obtain ground stability information from locations that have

traditionally been difficult to monitor, such as mined-out areas, active mining

stopes, retreat mining faces, and tailgate entries, cableless techniques will

be developed to monitor instruments remotely. A prototype miniaturized

data acquisition system is being constructed that can measure and record

strain readings remotely on 16 strain gauges for over 1 year without the

need for long lead wires. This system will be used in conjunction with a

new strain sensor and previously developed instrumented roof bolts. 

A sensor prototype has been developed that can measure rock movement

up to 20% strain. This sensor can be configured for different rock types. 

Critical information includes determinations of when rock movement

exceeds the strain limits of roof support systems; measurements of rock

shear displacement, which causes failure of roof bolts; and monitoring

changes in strain in three dimensions, which improves the design of an

adequate level of support to prevent ground failures.

 Both laboratory and field tests will be conducted on the miniature data

acquisition system and the strain sensor. Hazardous levels of horizontal,

vertical, and shear strain that can lead to rock failure will be detected using

this technology so that a warning signal can be given and corrective action

taken.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 23

A 23-ton truck showing points used to measure voltage

potentials that may be present on the exterior surface.

OVERHEAD POWER LINE CONTACT

ALARM FOR MOBILE EQUIPMENT

RESEARCHER: James C. Cawley

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

(412) 386-6648

KEYWORDS: Mining,

electrocution, power line, alarm,

crane, truck

BIBLIOGRAPHY

Hinze J [1996]. Analysis of

fatalities and injuries due to

power line contacts. J Constr

Eng Mgt 22(2):177-182.

NIOSH [1995]. NIOSH alert:

preventing electrocutions of

crane operators and crew

members working near overhead power lines. Cincinnati,

OH: U.S. Department of Health

and Human Services, Public

Health Service, Centers for

Disease Control and Prevention,

National Institute for Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 95-108.

Sacks HK, Cawley JC, Homce

GT, Yenchek MR [1999]. 

Feasibility study to reduce

injuries and fatalities caused by

contact of cranes, drill rigs, and

haul trucks with high-tension

lines. In: Proceedings of the

IEEE Industry Application

Society Annual Meeting

(October 4, 1999).

PURPOSE: Determine the electrical characteristics of

mobile equipment that accidentally contacts an overhead

power line. Design and test an effective alarm device to

warn vehicle operators and nearby support personnel of vehicles energized

due to accidental power line contact.

RESEARCH SUMMARY: Overhead electric power lines are a serious

electrocution hazard to crane, truck, and drill rig operators in the mining

industry. During 1980-97, at least 106 mobile equipment overhead-line

contact incidents were reported in the U.S. mining industry. These caused

106 injuries, of which 30% were fatal. Most involved cranes (39%), dumpbed trucks (22%), and drills (13%). The widespread use of a reliable

overhead power line contact alarm on mobile equipment could reduce the

number of injuries and fatalities from equipment-line contacts. A practical

contact alarm could also be applied in other industries where overhead

power lines are a hazard, such as construction, agriculture, broadcast

communications, and public utilities.

Initial research shows that electrical currents flowing through a vehicle

in contact with a high-voltage source are of sufficient magnitude to be

practically detected and trigger an alarm. An alarm device would warn the

equipment operator and nearby coworkers that the vehicle is an

electrocution hazard and should not be approached (or dismounted by the

operator). Clearly, victims in contact with the crane or a conductor

electrically connected to the crane (a control pendant or load line) at the

instant of contact with the power line would not be protected.

Overhead power line contact by current and voltage-sensing methods

were examined in the first year of this 2-year project. Both methods seem

feasible at this point. Voltage differences between surfaces in the operator

cab and along the operator’s egress path have been measured on three

vehicles and are being analyzed to determine under what circumstances

lethal voltage differences may exist. Based on the preferred method of

detection, a prototype device is to be constructed and subjected to

laboratory tests to verify its performance. In addition, load links and remote

controls may be studied as supplemental operator protective devices.
Spokane and Pittsburgh Research Laboratories

24 Office for Mine Safety and Health Research

Electromagnetic data acquisition

system.

INVESTIGATION OF ELECTROMAGNETIC

PRECURSORS TO ROCK BURSTING

RESEARCHER: Doug Scott

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Underground mining, electromagnetic emissions,

monitoring instruments

PURPOSE: Develop a method to monitor the rock

surrounding miners and establish a baseline for measuring

electromagnetic emissions during the mining cycle. 

RESEARCH SUMMARY: Highly stressed rock in stopes

continues to be a primary risk to the safety of miners in

underground mines, and failure of the rock results in both

 injuries and deaths. Novel methods need to be developed

that will alert miners to the possibility of imminent ground failure.

Acoustic and electromagnetic radiation emissions coincide when rock breaks. 

Acoustic monitoring of a rock mass to detect ground movement in deep

underground mines has been done successfully for several years. Electromagnetic

emissions associated with rock failure have been shown to occur in controlled

laboratory situations; however, such emissions have not been used to detect

imminent ground failure in deep underground mines. Monitoring electromagnetic

emissions in a rock mass during the mining cycle could provide one method to

warn miners of imminent ground failure. 

An electromagnetic monitoring system has been in operation intermittently at

the Galena Mine, Kellogg, ID, for several months. However, the data collected

are suspect because of inherent mine electromagnetic noise, such as electrical

interference from mine systems. 

The project will proceed in two phases. Phase 1 involves comparing the

original electromagnetic data with a controlled, independent electromagnetic

system to prove whether or not the original data are reliable. Work will involve

installation of an electromagnetic antenna system with an independent power

source in the Galena Mine, as well as an accelerometer and a data acquisition

system. Electromagnetic data from both the new system and the existing one will

be compared and analyzed. A report will be prepared that characterizes the

signals and provides recommendations for improving methods for recording

electromagnetic signals from the rock mass.

Phase 2 will proceed if the data analysis from the Phase 1 research proves

that this method is useful and reliable in detecting imminent ground failure in

underground mines. Phase 2 will involve installation of several electromagnetic

systems in mine stopes where miners may be in danger from ground failure

resulting from rock stress.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 25

Mine fire sensor array in the Safety Research Coal Mine.

SMART FIRE SENSORS 

RESEARCHER: John C. Edwards, Ph.D.

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Fires, mining,

detection

BIBLIOGRAPHY

Edwards JC, Franks RA, Friel

GF, Lazzara CP, Opferman JJ

[1999]. Mine fire detection in

the presence of diesel

emissions. In: Tien JC, ed. 

Proceedings of the Eight U.S.

Mine Ventilation Symposium. 

Rolla, MO: University of

Missouri-Rolla Press, pp. 295-

301.

Edwards JC, Friel GF, Franks

RA, Lazzara CP, Opferman JJ

[2000]. Mine fire source

discrimination using fire sensors

and neural network analysis. In:

Reuss DL, ed. Proceedings of

the 2000 Technical Meeting of

the Central States Section of the

Combustion Institute, pp. 207-

211.

Edwards JC, Friel GF, Franks

RA, Opferman JJ [1997]. Mine

fire detection under zero airflow

conditions. In: Ramani RV, ed. 

Proceedings of the Sixth

International Mine Ventilation

Congress (Pittsburgh, PA, May

17-22, 1997), chapter 52,

pp. 331-336.

PURPOSE: Examine new and improved mine fire

detection technologies for the protection of mine workers.

RESEARCH SUMMARY: The early and reliable detection of

underground mine fires is important for the safety of miners in the

workplace. Existing products of combustion (POC) mine fire sensors, as

well as reliable POC sensors, are being developed as smart sensor

technology with the capability to detect the fire, discriminate the fire

combustible source in a gaseous and particulate background, and provide a

mine fire location strategy in an underground mine. Diesel engines, welding,

and cutting operations create the gaseous and particulate emissions

background against which the sensors must discriminate. Gas sensor crossinterference effects from battery-charging operations and natural-occurring

sources are being accounted for in the sensor selection strategy.

The two methods that are being used to develop smart fire sensor

technology are (1) grouping fire sensors that are POC-specific and using a

neural network to provide this decision capability and (2) developing or

improving fire detector technology that will provide early-warning detection

while functioning reliably in atmospheres containing diesel exhaust or

welding and cutting emissions. Laboratory- and large-scale in-mine fire

experiments are being conducted to evaluate the sensors and deployment

strategy. The large-scale experiments are being conducted in the

Pittsburgh Research Laboratory’s Safety Research Coal Mine (SRCM). 

This in-mine research examines sensor response to signatures from

smoldering and flaming coal, electrical cable, and conveyor belt fires, and

flaming diesel fuel fires with and without nuisance background diesel

emissions. The most efficient arrays of multiple fire sensors, which include

chemical cell and metal oxide semiconductor gas sensors, and ionization and

optical smoke sensors, are being evaluated for mine fire combustible source

identification, discrimination of mine fire POC from diesel emissions, as a

supplement to chemical cell CO sensors that are cross-sensitive to H2 at a

battery-charging operation, and for early detection of very low CO-emitting

smoldering combustibles that produce visually obscuring smoke. This

research is being supported by modeling applica-tions of a computational

fluid dynamics computer program and a mine fire ventilation computer

program. Predictive modeling can provide guidelines to the fire signature,

its rate of change at a smart fire sensor location, and smoke reversal from a

fire in a ventilated airway. A partnership with a coal mine is being

established for an in-mine evaluation of new fire sensor technology. This

research is to be conducted in cooperation with the Mine Safety and Health

Administration, sensor manufacturers, and mine operators.
Spokane and Pittsburgh Research Laboratories

26 Office for Mine Safety and Health Research

PFC model of a void forming above a feeder.

DETECTION OF BRIDGING IN SURGE PILES

RESEARCHER: Steve Iverson, Jeff Johnson,

 Mark Larson, and William H.

 Schiffbauer 

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Surface mining,

surge piles, bridging, voids,

collapse

PURPOSE: Develop methods to detect and warn

operators of voids in coal surge piles.

RESEARCH SUMMARY: Bulldozers are used to move coal on surge

piles during pile expansion and when pushing coal to active feeders. These

activities can be extremely hazardous if a void forms within the pile above a

feeder. Because such voids are not visible from the surface, a bulldozer

could be driven over or near a void, causing a collapse that could engulf the

machine and injure or kill the operator. Eighteen fatalities have resulted

from surge pile accidents between 1980 and the end of 1999. Most of these

occurred because a void had formed in the pile and collapsed when the

dozer was driven over it.

This project is focused on developing methods to detect voids in surge

piles. Successful scaled tests using resistivity to detect voids have been

completed. The use of infrared and ultrasound techniques that can be read

in real time are being investigated. Ground-penetrating radar has been

reviewed, but no tests of this technique are planned. Another method

involves real-time comparisons of pile volume around drawpoints and the

volume drawn. Relative deviations in the slopes of datapoints over time

may be an indicator of void formation. This concept is being tested with a

numerical modeling simulation using Particle Flow Code (PFC). Another

investigation involves the development of an on-board global positioning

system (GPS) for use in tracking dozers on a surge pile in real time.

Testing coal samples to determine strength properties is important to

understanding flow conditions in a surge pile, especially when the coal is

subjected to loads and vibration from a dozer. The data could also be useful

for inputting into PFC models. Testing of coal samples from surge piles is

planned following the construction of a shear test apparatus.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 27

Pincher arm device for mechanically picking debris

from a grizzly.

INJURY PREVENTION AND

EQUIPMENT DESIGN

MATERIAL HANDLING ACCIDENT

REDUCTION IN UNDERGROUND MINES

RESEARCHER: Bill Stewart, Curtis Clark, 

 and Phil Patton

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Mining,

materials handling, overexertion,

injuries

PURPOSE: Improve methods and procedures to reduce or prevent

injuries associated with materials handling in underground mines.

RESEARCH SUMMARY: Injuries while handling materials in underground mines continue to be a major safety problem. The approach taken

in this project is to visit mines to identify (1) the kind of activities that result

in injuries and (2) best practices and innovative solutions to common manual

materials handling problems.

In 1999, 12 underground metal/nonmetal and 8 underground coal mines

in 9 States were visited and/or materials handling accidents, needs, and

innovative solutions to these problems were investigated. A total of 860

accidents, injuries, and illnesses at these mines were reported to the Mine

Safety and Health Administration in 1999. Of these, 206 (24%) were

classified as “handling of materials” accidents. Forty-six of these accidents

resulted in restricted activities, 100 resulted in days away from work,

9 resulted in permanent disabilities, and the rest were injuries with no lost

work time or restricted activity. Overexertion while manually moving

(lifting, pulling, pushing, etc.) objects accounted for 53% of the

materials handling accidents; of these, 64 were back injuries. 

Activities in which the most overexertion injuries occur generally involve lifting. Manually cleaning debris, such as timbers, rock bolts, wire

mesh, etc., from grizzlies covering ore passes also results in overexertion

injuries. In this project, a grabber arm attached to an impact hammer head

was designed to pick up the debris mechanically. This device can be

operated from the control panel for the impact hammer. Another task is to

modify and test an off-the-shelf manipulator. Making the manipulator

mobile and finding or developing a grabber attachment that can pick up

objects of different shapes and sizes are keys to the research. If these

devices prove to be successful, many of the manual activities that cause

overexertion injuries could be mechanized.

Work has begun on a best-practices handbook that will include current

but innovative materials handling methods, new materials handling ideas and

practices, and detailed analyses (fault tree analysis) of materials handling

failures and events leading to back injuries.
Spokane and Pittsburgh Research Laboratories

28 Office for Mine Safety and Health Research

Back injuries can result from shocks to an operator as

loads of mine ore and waste rock are dumped onto a

truck bed.

ENGINEERING CONTROLS FOR REDUCING

JOLTING AND JARRING INJURIES IN

SURFACE MINES

RESEARCHERS: Fred Biggs and Rusty Miller

AFFILIATION: Spokane Research Laboratory 

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Vibration,

shocks, jolting, jarring, haulage

trucks

BIBLIOGRAPHY

Biggs FR, Utt W [2000]. Jolting

and jarring injuries in surface

mine haul trucks. Presentation

at 31st Annual Institute on

Mining Health, Safety, and

Research (Roanoke, VA,

August 27-30).

Miller RE, Boman P, Walsen J,

Rhoades S, Gibbs R [1999]. 

Tying acceleration and GPS

location information together to

create a mine management tool

(Denver, CO, March 1-3). 

SME preprint 99-118. Littleton,

CO: Society for Mining,

Metallurgy, and Exploration,

Inc.

Miller RE, Boman P, Rhoades

S, Gibbs R [2000]. Acceleration

and GPS data monitor truckhaulage jolts. Min Eng

52(8):20-22.

PURPOSE: Devise and promote the use of engineering

controls to minimize jolting and jarring injuries among

haulage truck and other heavy equipment operators in

metal/nonmetal surface mines.

RESEARCH SUMMARY: During the last several years, the number of

surface mines in the West has increased. At the same time, larger haulage

trucks, increased production demands, and more people in the workforce

have led to more worker injuries and fatalities. During 1986-95, truck

drivers accounted for approximately 63% (76 of 120) of the fatalities and

60% (3,551 of 5,569) of the lost-time injuries in surface mines. 

Very little research has been done related specifically to shock trauma

injuries—jolting and jarring injuries caused by haulage trucks—nor to the

development of engineering controls to reduce such injuries.

Tasks in this project include—

• Development of software for linking information from global positioning

systems (GPS) with jolting and jarring incidences. 

• Bench-scale tests to characterize and isolate jolting and jarring elements

so that shock loads on an operator can be identified.

• Definition of current engineering controls used to minimize exposure to

health hazards and note their limitations.

• Field tests of a device called the “BackCycler” to evaluate its

effectiveness as a method of conditioning a person’s back to prevent

injuries.

• Tests and evaluations of other engineering controls.

Using this process, we hope to lessen operator exposure to shock

trauma and reduce lost-time injuries to haulage truck drivers.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 29

Jolts and jars while operating heavy construction

equipment can contribute to lower back injuries.

REDUCING INJURY RISK FROM JOLTING

AND JARRING ON MOBILE EQUIPMENT 

RESEARCHERS: Fred Biggs and Walter Utt

AFFILIATION: Spokane Research Laboratory 

National Institute for

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Vibration,

shocks, jolting, jarring, back

injuries

PURPOSE: To reduce back injuries resulting from jolting

and jarring while operating mobile equipment used in

mining, construction, and agriculture. 

RESEARCH SUMMARY: Data from the Construction Chart Book and

U.S. Bureau of Labor statistics show that, in 1994, 24.5% of the nonfatal

injuries in the construction industry were back injuries. Back injuries are

common in other industries as well, including agriculture; of the lost-time

injuries to farm workers in 1993, 15% are estimated to have been back

injuries. Data from the Washington State Department of Labor and

Industries for 1992-97 show the average annual cost of back injuries to be

$175.7 million, which is about twice the amount for any other category.

While a great deal of research has been done on whole-body vibration

and its effects on the human body, very little has been done on the effects

of single or multiple jolts. Little is known about how severe a jolt must be to

result in an injury and what factors may contribute to an injury. It is

important to understand the mechanism whereby an injury may be caused

by a single jolt.

This new project is collaborative research among NIOSH’s Spokane

and Pittsburgh Research Laboratories and the Division of Applied Research

and Technology.

Tasks in this project include—

• Characterization of the shocks drivers experience while operating

selected types of construction and agricultural equipment. 

• Identification and design of intervention techniques.

• Demonstration of the most promising techniques.

• Transfer of research results and technologies for implementation and

reduction of jolting- and jarring-related injuries.
Spokane and Pittsburgh Research Laboratories

30 Office for Mine Safety and Health Research

Examination of a flexible haulage truck ladder.

ERGONOMICS INTERVENTIONS IN MINING

RESEARCHER: Fred C. Turin

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

(412) 386-6648 

KEYWORDS: Mining,

ergonomics, musculoskeletal

disorders

BIBLIOGRAPHY

Gallagher S [1998]. Ergonomic

issues in mining. In: Karwowski

W, Marras WS, eds. The

occupational ergonomics

handbook. Boca Raton, FL:

CRC Press LLC, pp. 1893-

1915.

Winn F, Biersner R, Morrissey

S [1996]. Exposure probabilities

to ergonomic hazards among

miners. Int J Ind Ergonomics

18:417-422.

Zhuang Z, Groce D [1995]. 

The national occupational health

survey of mining: magnitude of

potential exposures to

musculoskeletal overload

conditions. In: Bittner AC,

Champney PC, eds. Advances

in Industrial Ergonomics and

Safety VII. London, U.K.:

Taylor and Francis, pp. 273-280.

PURPOSE: Assess ergonomic risk factors in select

mining environments. Develop, implement, and evaluate

ergonomics interventions.

RESEARCH SUMMARY: In 1998, the Mine Safety and Health Administration (MSHA) submitted a formal request to NIOSH to investigate

musculoskeletal disorders (MSDs) in the mining industry. MSHA wanted a

better understanding of the extent of MSD risk factors and evidence that

ergonomics interventions are effective. An earlier analysis of National

Occupational Health Survey of Mining (NOHSM) data showed that

exposures to ergonomic hazards for mine workers were high compared to

those in nonmining occupations. Another study that examined NOHSM

data reported that the three most common musculoskeletal overload

conditions in mining were neck and/or back, arm and shoulder, and heavy

lifting. At least 35% of mine workers were potentially exposed to each of

these conditions.

The research is planned as a two-phase effort. The first phase consists

of risk factor assessments at four cooperating mine sites, with emphasis on

MSDs. The second phase involves development, implementation, and

evaluation of ergonomics interventions at one or two cooperating mine

operations.

Risk factor assessments have been completed at an underground coal

operation, surface copper operation, and surface phosphate operation. An

evaluation is underway at an underground limestone operation. Results are

being used to identify activities that provide significant risk for injury and to

develop general risk reduction strategies. The primary benefit to

cooperating mine sites is a better understanding of the types of ergonomic

risk factors that exist at their operations and how to identify them. In

particular, once risk factors have been identified, they can be prioritized and

strategies for reducing them can be developed.

Specifics of the phase 2 work depend on phase 1 findings and

identification of cooperating mine sites. The research team has met with

representatives of two mine companies that have expressed a strong

interest in participating in the second phase of this project, and partnerships

are being pursued.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 31

 Newly designed ergonomic handles may reduce the

 fatigue experienced by jackleg drill operators.

INJURY PREVENTION FOR METAL/

NONMETAL DRILLING AND BOLTING

RESEARCHERS: Robert McKibbin 

 and Curtis Clark

AFFILIATION: Spokane Research Laboratory 

National Institute for

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Mining, low

back disorders, materials

handling, jackleg, drilling safety,

noise reduction, ergonomics,

hard rock

BIBLIOGRAPHY

Kramer B [2000]. Weighty

issues. Spokesman-Review

(Spokane, WA), Jan 18, p. A11.

McKibbin R [1999]. 

Development of a lightweight

jackleg. Presentation at NIOSH

Open Industry Briefing, 105th

annual meeting of Northwest

Mining Association, Spokane,

WA, November 30.

PURPOSE: Identify the causes of injuries associated 

 with drilling and bolting operations in metal/nonmetal mines

and develop the technology to reduce or eliminate the risk of injury.

RESEARCH SUMMARY: Mine Safety and Health Administration

(MSHA) statistics have shown that in an average year there are 2 fatalities

and more than 200 injuries in drilling and bolting operations in

metal/nonmetal mines. These account for 5% and 4% of all fatalities and

injuries, respectively, in metal/nonmetal mines.

Project staff have highlighted a number of areas in which reductions in

accidents might be realized. These include crushing injuries on carriage and

jumbo drills; getting caught in rotating drill components; excessive weight,

noise, and vibration of jackleg drills; slips and falls while getting on and off

drills; rock falls while barring down or bolting; and handling steel or

supplies. A significant finding was the number of injuries related to the

weight (about 103 pounds) of jackleg drills. Such injuries result in about 35

lost-time injuries per year, or about 17% of all drilling and bolting injuries. 

Almost all of these are low-back injuries.

Project staff decided that one course of research offering a good

probability of short-term success would be the fabrication and testing of an

improved jackleg drill. The initial goal was to reduce the weight to

83 pounds without a reduction in the specific energy of drilling. A drill has

been constructed in which several components are made of aluminum or

titanium, resulting in a drill that is 20% lighter than a standard steel drill. 

Initial tests of this prototype in concrete blocks have shown that the drill is

capable of drilling with no loss of penetration rate.

In addition to the weight reduction already achieved, project staff have

designed and are in the process of fabricating several alternative jackleg

drill handles. These designs address the concerns regarding vibration and

fatigue experienced by the miners and include both vibration dampening and

improved ergonomic shapes.

It remains to test these various improvements under actual mining

conditions. Experienced hard-rock miners will serve as the final authority

as to the efficacy of this research.
Spokane and Pittsburgh Research Laboratories

32 Office for Mine Safety and Health Research

REDUCING SLIPPING AND FALLING

INJURIES AT SURFACE MINES

RESEARCHERS: John K. Owens and 

 Gregory G. Miller

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Slipping, falling,

and tripping injuries; surface

mining; safety; accident

prevention

PURPOSE: (1) Identify the sources of slips and falls at surface mines

among older workers, (2) design intervention techniques to prevent slip and

fall injuries, (3) demonstrate the most promising interventions, focusing on

mine equipment design and human factors, and (4) transfer research results

and technologies to the mining industry.

RESEARCH SUMMARY: A significant fraction of accidents in the

workplace is associated with tripping and slipping accidents. This is a

particular problem in the mining industry where the average age of

employees is 47 years. The severity of these accidents is often greater with

older workers because of diminished flexibility with age. According to

Mine Safety and Health Administration (MSHA) accident data for surface

mines for 1992-94, the most common types of lost-time injuries were caused

by handling materials (30%) and slips/falls (27%). The injuries resulting

from slips and falls are sprains, bruises, and fractures of trunks or legs. 

Surface metal and nonmetal mine accident data for 1986-97 show that 11%

of the back injuries to equipment operators were caused from slips and

falls. Of these, 65% occurred while an operator was mounting or

dismounting from a vehicle using the ladder portion of the steps.

The reduction of slipping and falling injuries would be of significant

benefit not only in mining, but in the construction industry as well. Data

from the U.S. Bureau of Labor Statistics for 1994 show that 22.8 % of the

lost-time injuries in the construction industry were slip and fall injuries.

The investigative approach to reduce slipping and falling injuries will

focus on mine equipment design and human factors. Equipment design

research will include improved methods of mounting and dismounting

equipment; location of handholds, steps, and ladders; ladder design; slipresistant walking surfaces; and boot-cleaning devices. Human factor

research will include analyses of older miners’ risks for slipping and falling

injuries using MSHA accident database and surveillance data; laboratory

and field studies to identify risks among mine personnel for slipping and

falling injuries; and development of effective behavioral, organizational,

and/or educational interventions to address the leading causes of slip and

fall injuries.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 33

Computer modeling assists in seat research, and a full-scale mockup validates

roof bolter models.

HUMAN FACTORS DESIGN FOR MACHINE

SAFETY

RESEARCHER: Dean H. Ambrose

AFFILIATION: Pittsburgh Research Laboratory

 National Institute for 

 Occupational Safety and Health

 (412) 386-6648

KEYWORDS: Mining,

construction, and agriculture

equipment; ergonomics;

modeling; vibration; machine

design and safety

BIBLIOGRAPHY

Ambrose DH [2000]. A

simulation approach analyzing

random motion events between

a machine and its operator. In:

Digital Human Modeling for

Design and Engineering

Conference and Exposition

(Dearborn, MI, June 6-8, 2000). 

Society of Automotive

Engineers printed article

No. 2000-01-2160.

Gallagher S, Mayton AG,

Merkel R [1998]. An improved

seat for underground mobile

equipment [Abstract]. In:

Abstracts - American Industrial

Hygiene Conference &

Exposition, p. 13.

Mayton AG, Merkel R,

Gallagher S [1999]. Improved

seat reduces jarring/jolting for

operators of low-coal shuttle

cars. Min Eng 51(12):52-56.

PURPOSE: Develop machine design guidelines and improved hardware to reduce injuries to personnel operating

and working near mining equipment.

RESEARCH SUMMARY: Operational, functional, or

structural design weaknesses of machinery continue to be

associated with many fatalities and injuries. Analysis of

accident data for 1993-96 shows that, for underground coal 

mining machinery injuries, the fatality rate is 0.0374

 (incidences per 200,000 hours) and the injury rate is 6.833. 

 In 1997, 32% of all injuries to underground coal miners

working in the extraction area of the mine were attributed to roof bolting

activities. Jolting/jarring and operator/machine interactions in mobile

haulage equipment are a leading cause of injury.

The approach is to identify machine hazards through surveillance data

and stakeholder input and to develop engineered interventions through the

application of human factors design principles, computer-based design and

analysis tools, and laboratory and field experimentation. Specific machine

issues currently being investigated are safe roof bolter appendage speed

and the jarring/jolting of mobile equipment operators. The bolter research

involves the use of computer models in addition to laboratory and field

experimentation to study the machine function and develop recommendations for safer boom speeds. Mockup tests with human subjects are

being used to validate the bolter models. The operator jarring/jolting

research involves computer modeling, the vibration testing facility, and

laboratory and field research. Specific improvements to seating and

alternative suspension systems are being evaluated for isolating the operator

from excessive jolting. In FY2000, the jolting/jarring research was expanded beyond mining to construction and agriculture. A roof bolting

manufacturer, a shuttle car manufacturer, and machine seat manufacturers

are collaborating on this research. This project is producing design

guidelines and improved hardware related to equipment hazards to improve

machine safety in the mining, construction, and agriculture industries.
Spokane and Pittsburgh Research Laboratories

34 Office for Mine Safety and Health Research

Sensitive ground fault relays can protect against

electrocutions on underground mine circuits.

FUNDAMENTAL STUDIES IN ELECTRICAL

HAZARDS

RESEARCHER: Michael R. Yenchek

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

(412) 386-6648

KEYWORDS: Electrical

shock, arcing, burns, mining,

construction, safety, lightning

BIBLIOGRAPHY

Novak T, Fisher TJ [2000]. 

Lightning propagation through

the earth and its potential for

methane ignitions in abandoned

areas of underground coal

mines. In: Proceedings of the

2000 IEEE Industry

Applications Society Annual

Meeting.

Yenchek MR, Cawley JC,

Brautigam AL, Peterson JS

[2000]. Distinguishing motor

starts from short circuits through

phase angle measurements. In:

Proceedings of the 2000 IEEE

Industry Applications Society

Annual Meeting.

PURPOSE: Identify, analyze, and classify electrocutions

and electrical injuries across industries and determine

appropriate strategies and technologies to reduce the

occurrence of these events.

RESEARCH SUMMARY: Electrocutions account for more than 5% of

all occupational fatalities, 14% of all deaths in the construction industry, and

5% of all deaths in the mining industry. Moreover, many of the systemic

causes of electrocutions also result in flash and burn injuries, fires, and

explosions. Mitigation of these hazards often involves similar practices and

control technologies regardless of the industry. Some industries, such as

underground coal, use more advanced technologies than others to prevent

electrocutions. Accordingly, the practices may be more beneficial to the

construction industry, among others. The underground coal industry may

benefit from the technologies of other industries in realms such as lightning

protection, an area in which there is concern because of lightning-initiated

gas explosions in gob areas of the mine.

In ongoing work, surveillance groups within NIOSH have been conulted to identify occupational incident databases, appropriate severity

measures, and methods to categorize incident criteria. Federal, State, and

private data are being searched for information regarding fatal and nonfatal

incidents involving electricity over the past decade. A questionnaire is being

compiled to assist researchers in analyzing incident narratives. Queries are

arranged in the following categories: environment, equipment, personnel,

work practices, and medical.

Computer models have been used to evaluate the likelihood that a

lightning strike above underground coal mines may be communicated

through the overburden and cause an ignition of methane-air atmospheres in

abandoned gob areas. Simulations have been done at various overburden

depths and soil resistivities. Fast Fourier transform analyses show that the

presence of a steel-cased borehole in the vicinity of the strike enhances the

possibility of a lightning-induced ignition underground. Hardware is being

procured to record voltages and currents that may be communicated

underground. Underground findings will be time-correlated with lightning

strike records on the surface.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 35

Rear upset test with mannequin.

NEW TECHNOLOGY TO INCREASE ROPS

USE ON TRACTORS

RESEARCHER: Timothy J. Lutz

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

(412) 386-6648

KEYWORDS: Injury

prevention, ROPS, tractors,

rollovers

PURPOSE: Design, develop, and evaluate rollover

protection systems (ROPS) technology to equip

significantly more tractors with ROPS.

RESEARCH SUMMARY: Data show that over 60% of tractors in use in

1993 did not have ROPS installed; most were older tractors. ROPS have

been proven as an effective safety device to prevent fatalities due to tractor

rollovers. On average, 119 people died each year because of tractor

rollovers during 1992-95. The use of ROPS is almost universally

recommended as the key factor in reducing the fatality rate due to tractor

rollovers. The long-term objective of this project addresses the Healthy

People 2010 goal to increase the proportion of agricultural production

tractors fitted with rollover protective systems to 100%. Cost-effective

alternatives to original equipment manufacturer rollbars are needed for

farmers to consider installing rollbars on older tractors. This project also

supports the National Occupational Research Agenda (NORA) traumatic

injuries research area. Information is to be shared with groups establishing

ROPS certification standards, such as the American Society of Agricultural

Engineers and the Society of Automotive Engineers.

This is a joint Pittsburgh Research Laboratory/Division of Safety

Research safety engineering project that is working on a common problem:

too many tractors still do not have ROPS. Innovative ROPS are being

designed, developed, and evaluated. During 2000, 17 rollover tests were

conducted using a remote-control Ford 4600 agricultural tractor outfitted

with various ROPS. The tractor control system had no failures during the

testing.

Fifteen to twenty rollover tests are planned during 2001. The roll

sensors and different rollbar configurations are to be tested for reliability,

integrity, and shock resistance.
Spokane and Pittsburgh Research Laboratories

36 Office for Mine Safety and Health Research

Filming a video underground.

TRAINING AND EDUCATION

INTERACTIVE TRAINING AND

EDUCATIONAL DEVELOPMENT

RESEARCHERS: Elaine Cullen, Marc Filigenzi,

 and Tim Orr

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Mining, safety

training, virtual reality, computer

visualization

BIBLIOGRAPHY

Cullen E [2000]. Mine safety

training, past, present, and

future. In: Minesafe

International 2000 (Perth,

Australia, September 3-8), 

pp. 151-154.

NIOSH [1999]. Explosives

underground: handling

explosives in modern mines. 

Videocassette.

NIOSH [2000]. Miner Mike

saves the day, or ground

support...it’s important. 

Videocassette.

NIOSH [2000]. Rock falls:

preventing rock fall injuries in

underground mines. 

Videocassette.

NIOSH [2000]. 

TECHNOLOGY NEWS 482:

Ground support safety training

video. Spokane, WA: U.S.

Department of Health and

Human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute for Occupational Safety and Health.

PURPOSE: Develop multimedia training tools that can be used to

provide safety training to miners.

RESEARCH SUMMARY: A NIOSH study on occupational deaths

during 1990-99 indicated that, in the mining industry, the average annual

fatality rate is 26 per 100,000 workers. Mining is also the highest risk

industry in 23 States and accounts for the largest number of occupational

deaths in 3 States. Researchers believe that the use of enhanced computer

visualization and multimedia training tools will help reduce these fatality and

injury numbers.

The first objective of this work is to develop, evaluate, and refine a

multimedia computer program that can be used by the mining industry to

train miners in hazard recognition, accident avoidance, equipment use, and

general mine safety. This multimedia program will enhance current training

techniques by providing a real-time, visually appealing interactive training

environment for mine workers. The program can record trainee scores and

evaluate the effectiveness of the training techniques. The inherent

flexibility of this type of program will allow easy and rapid updating and

modification of training material.

The second objective is to develop video training modules. Mine safety

professionals provide input to determining topics and issues, assist in

ensuring that story boards and scripts are technically correct and relevant to

trainees, and ensure that mine sites are available to show the topics under

consideration effectively. They will also evaluate resulting products by

assessing reaction to the videos during training sessions and by soliciting

feedback from trainees on what was learned.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 37

A PC screensaver that depicts the correct way to don a

self-rescuer shows how effective training can be applied

to new multimedia products.

EVALUATION OF INTERACTIVE MINE

SAFETY AND HEALTH TRAINING METHODS

RESEARCHER: Robert F. Randolph

AFFILIATION: Pittsburgh Research Laboratory

National Institute for

Occupational Safety and Health

(412) 386-6648

KEYWORDS: Mining,

intervention, training,

effectiveness

BIBLIOGRAPHY

Loos GP, Fowler T [1999]. A

model for research on training

effectiveness (TIER). 

Cincinnati, OH: U.S.

Department of Health and

Human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute for

Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 99-142.

Randolph RF, Steiner LJ [1996]. 

Mining health and safety on the

Internet. In: Thompson SD,

Grayson RL, Wang YJ, eds. 

Proceedings of the Fifth

Conference on the Use of

Computers in the Coal Industry. 

Morgantown, WV: West

Virginia University, pp. 178-184.

Rethi LL, Barrett EA [2000]. 

Development and evaluation of

a training exercise for

construction, maintenance and

repair work activities. In:

Proceedings of the 31st Annual

Institute on Mining Health,

Safety and Research (Roanoke,

VA, August 27-30, 2000).

PURPOSE: Determine the real-world effectiveness of a

variety of low- and high-technology safety and health

training approaches for miners.

RESEARCH SUMMARY: Mining occurs in

unpredictable and dynamic environments where miners play an important

role in preventing illnesses and injuries. Their skills at identifying and

correcting or avoiding hazards are a critical supplement to engineering

control approaches. Because these skills are unlikely to arise

spontaneously, they must be imparted through effective training. 

Unfortunately, the effectiveness of the training delivered to the mining

community is rarely measured. Interactive instructional technologies

provide an opportunity for providing training content in a form that can be

more readily measured. Also, the anticipated increased efficiencies

available through these technologies offer better results from the scarce

resources available.

Prototype interactive training systems have been developed and

evaluated for mine safety and health training. These systems are based on

a range of technologies, from low-cost latent-image methods to

computerized authoring systems. The prototypes are being evaluated

through field testing with miners, trainers, and safety personnel.

A training exercise completed for mining called “Hazard Recognition

Training Program: Construction, Maintenance, and Repair Activities” was

so well received that Pittsburgh Research Laboratory researchers are

assisting another NIOSH laboratory in extending the training exercise to

falls in the construction industry. Also, a computerized machine guarding

exercise has been successfully beta-tested and is undergoing field trials to

compare it with traditional training methods.

Another project goal is to improve the availability of high-quality training

materials. A new distribution system was developed so that NIOSH miner

training materials can be ordered by telephone, fax, or e-mail. This system

has already distributed more than 27,000 training items since January 1999. 

Nineteen training products have been posted on the NIOSH Web site

(www.cdc.gov/niosh) for more convenient access.
Spokane and Pittsburgh Research Laboratories

38 Office for Mine Safety and Health Research

In 1999, over 50% of the injured sand and gravel miners

in the United States had less than 2 years of total mining

experience.

EVALUATING TOOLBOX TRAINING

FOR CONSTRUCTION AND MINING

RESEARCHERS: C.M.K. Boldt and Floyd Varley

AFFILIATION: Spokane Research Laboratory 

National Institute for

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Mining, sand

and gravel, training

BIBLIOGRAPHY

Boldt CMK [2000]. Toolbox

training for sand and gravel

miners. Presentation at Arizona

State Inspector’s 7th Annual

Mine Safety and Health

Seminar (Phoenix, AZ, May

22).

PURPOSE: Develop toolbox training materials and

evaluate their effectiveness for sand and gravel miners.

RESEARCH SUMMARY: “Toolbox” or “tailgate”

training (weekly sessions usually about 10 to 15 minutes long) conducted

on-site prior to work shifts and involving work crews are a primary mode of

worker occupational safety and health training used in small construction

companies. Toolbox training is also used in other sectors of industry,

including mining and agriculture. However, the toolbox training approach

has not been adequately evaluated. This project will (1) identify and review

existing toolbox talks or series addressing construction, mining, or

agriculture, (2) identify salient characteristics and different types of toolbox

training materials, (3) prepare toolbox talks for one high-risk sector (sand

and gravel) in mining and one high-risk sector (residential building) in

construction, and (4) evaluate the effectiveness of representative examples

of existing toolbox talks among small construction and mining companies. 

Each toolbox talk will contain a “story” about one or more serious or fatal

injuries based on available injury and fatality investigative reports from

NIOSH, the Mine Safety and Health Administration, the Occupational

Safety and Health Administration, and other sources. Field evaluations in

sand and gravel mines and during residential building construction will be

conducted to determine whether the NIOSH toolbox talks produce the

desired results, that is, increased knowledge, appropriate changes in

attitudes, positive changes in behavior and work practices, and sustained

positive changes. The effectiveness of the NIOSH toolbox talks based on

didactic material will be evaluated and compared.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 39

Scene from virtual mine training program.

ACCIDENT RECONSTRUCTION AND

TRAINING FOR METAL/NONMETAL MINES

RESEARCHERS: Marc Filigenzi, Timothy Orr, 

and Todd Ruff

AFFILIATION: Spokane Research Laboratory 

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Mining, hazard

recognition, virtual reality,

rescue and evacuation training

BIBLIOGRAPHY

Filigenzi MT, Orr TJ, Ruff TM

[1999]. Computerized accident

reconstruction and training for

metal/nonmetal mines. Amer J

Ind Med Suppl 1 Sep:116-118.

Filigenzi MT, Orr TJ, Ruff TM

[1999]. Hazard recognition:

computer-based simulation. 

Presentation at 30th Annual

Institute on Mining Health,

Safety and Research

(September).

Filigenzi MT, Orr TJ, Ruff TM

[2000]. Virtual reality for mine

safety training. Appl Occup

Env Hyg, June.

PURPOSE: Develop computer visualization techniques

that can be used to reconstruct accident sites on the

computer accurately. Use these techniques to develop

computerized models of mines as part of a training program to teach hazard

recognition and evacuation and rescue procedures to mine employees.

RESEARCH SUMMARY: Most current information dissemination and

training methods are lacking in that they depend on training materials that

are not specific to each mine. In addition, they are often outdated. Mine

evacuation and rescue drills are expensive and time-consuming and cannot

be practiced at regular intervals. New methods are needed to teach

personnel about the hazards in mines, and about evacuation and rescue

routes and procedures. By improving safety training in theses areas,

researchers hope to increase worker safety and reduce accidents in the

mines.

This project addresses two tasks.

(1) Accident reconstruction. In mining, as in most industries, injuries

or death may result from equipment failure or human error. Accident

investigators are often able to pinpoint the exact cause of the accident. 

However, the results of the accident investigations are published in a text

format and are often difficult for a reader to absorb. The purpose of this

task is to develop computer modeling and visualization techniques that will

allow accident investigators to re-create an accident accurately on a

computer. This computerized accident re-creation will be used to educate

workers about the causes and results of the accident.

(2) Training methods for hazard recognition and mine evacuation

and rescue. New methods of training mine personnel in hazard recognition

and mine evacuation and rescue procedures are being investigated. 

Existing software technology is being applied to create realistic threedimensional representations of specific mine sites. By running this

software, mine employees are immersed in a “virtual mine” in which they

are taught to recognize and avoid hazardous situations. In addition, the

trainees use the virtual mines to follow rescue and escape routes and

practice procedures particular to the mine they work in.
Spokane and Pittsburgh Research Laboratories

40 Office for Mine Safety and Health Research

Fighting a conveyor belt fire at Lake Lynn Laboratory.

MINE RESCUE AND RESPONSE

RESEARCHER: Ronald S. Conti

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Fires, mining,

preparedness, emergency

responders, mine rescue training

BIBLIOGRAPHY

Conti RS, Chasko LL [2000]. 

Technologies for today’s mine

emergency responders. In:

Proceedings of the Seventh

Annual Conference of The

International Emergency

Management Society (TIEMS),

pp. 105-121.

Conti RS, Chasko LL, Cool JD

[1999]. An overview of

technology and training

simulations for mine rescue

teams. In: Proceedings of the

28th International Conference

of Safety in Mines Research

Institutes (Sinaia, Romania). 

Vol. II, pp. 521-538.

Conti RS, Chasko LL, Lazzara

CP, Braselton G [2000]. An

underground coal mine fire

preparedness and response

checklist: the instrument. 

Pittsburgh, PA: U.S.

Department of Health and

Human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute for

Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 2000-144, IC 9452.

PURPOSE: Develop realistic training simulations for

responders to mine emergencies and evaluate technology

that can be used during exploration and firefighting.

RESEARCH SUMMARY: Fires remain a common

occurrence during mining operations. During 1990-99, the Mine Safety and

Health Administration (MSHA) reported more than 153 fires at coal mines

(fires lasting more than 30 minutes after discovery, or causing injury), or an

average of 15 fires per year. These fires resulted in 1 fatality and

46 injuries. A significantly higher number of unreportable fires are believed

to have actually occurred. Preparedness is an essential element of any

underground mine’s strategic plan in dealing with an unexpected event such

as a fire. It is important that the fire be detected in the incipient stage and

that well-trained and fully equipped miners respond during that crucial

period. Any delay can mean serious injuries and the loss of the mine. 

A fully implemented fire preparedness and response plan is essential in

reducing the probability and seriousness of a mine fire.

A study conducted by MSHA indicated that there are 274 State and

company mine rescue teams in the United States (133 coal mine teams and

141 metal/nonmetal mine teams) composed of 2,000 rescue team members. 

These statistics show a drastic decline in the number of teams over the last

decade as the number of mines decrease. Very often, rescue teams

receive hands-on training during actual emergencies or in simulated mine

environments with placards to identify objects and hazards. This dedicated

group of miners often place their lives in jeopardy to save others.

Partnerships were established with two coal mines and a State agency

to evaluate their mine rescue teams, and data have been collected from five

mines in Colorado, Illinois, Pennsylvania, South Dakota, and Utah to determine their fire preparedness and response capabilities. Interviews with

mine rescue teams and fire brigade members at Lake Lynn Laboratory and

operating mines were conducted to determine current strengths and needs. 

These data were used to develop mine rescue training simulations and

technologies for firefighting, exploration, and escape. A lighted lifeline for

emergency responders was developed. The lifeline alleviated tripping and

falling problems, and the different colored light wires allow the team

members to easily find their usual position along the lifeline when ex-ploring

in darkness and smoke-filled passageways. An underground coal mine fire

preparedness and response checklist was completed and is intended to

enhance the safety of mine workers by improving the state of fire

preparedness at underground mines. A similar checklist is being developed

for metal/nonmetal mines.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 41

A miner is tested in the mobile audiometric test unit.

INTERVENTION THROUGH EDUCATION AND

TRAINING TO PREVENT HEARING LOSS

AMONG MINERS

RESEARCHER: Patricia L. Moisan

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Noise,

hearing loss, prevention,

intervention, training,

education

BIBLIOGRAPHY

Franks JR, Stephenson

MR, Merry CJ [1996]. 

Preventing occupational

hearing loss: a practical

guide. Cincinnati, OH:

U.S. Department of

Health and Human

Services, Public Health

Service, Centers for

Disease Control and

Prevention, National

Institute for Occupational

Safety and Health,

DHHS (NIOSH)

Publication No. 96-110.

PURPOSE: Educate miners regarding hearing

conservation measures and train them to recognize ways

that they may assist in the reduction of occupational hearing

loss.

RESEARCH SUMMARY: Noise is one of the most

pervasive health hazards in mining. Exposure to highintensity sound levels results in the development of noiseinduced hearing loss (NIHL). One consequence of NIHL is a reduced quality of

life due to the inability to communicate with family, friends, and the general public. 

However, this normally occurs after the hearing loss has progressed too far, and

the damage is irreversible. Although excessive noise exposure can cause a

permanent disability, NIHL is nearly always preventable.

The goal of this project is to educate miners regarding hearing conservation

procedures and train them to recognize ways that they may assist with the hearing

loss prevention process. Site visits are conducted nationwide with the Pittsburgh

Research Laboratory’s state-of-the-art mobile audiometric test unit. Hearing tests

and individual fit-testing of personal hearing protection (i.e., earplugs) are

performed on noise-exposed miners. By explaining the results to each individual,

the problem becomes a “personal” one that a miner has a vested interest in. 

Results of the earplug fit-testing are analyzed and compared to the amount of

hearing loss observed to determine whether individuals with a hearing loss are

more inclined to achieve a better fit with their earplugs. Additionally, the mobile

unit has the capability to show a hearing loss training video or computerized

hearing loss demonstration to each participant.

This intervention project is intended to educate and empower miners by

encouraging each miner to become more proactive in efforts to preserve his or her

hearing. The best use of available educational activities will be assessed as the

project progresses. Successful intervention methods will be further tested and

disseminated more widely among the different mining sectors. This has recently

become even more important since a more stringent noise regulation was

promulgated for the mining community. Therefore, compliance with the new

regulation and increased awareness on the part of all miners will likely provide the

necessary incentives for future prevention of NIHL.
Spokane and Pittsburgh Research Laboratories

42 Office for Mine Safety and Health Research

Stress monitoring system field tested for assessing

coal bumps.

GROUND CONTROL

SAFETY DESIGN FOR UNDERGROUND

MINE STABILITY

RESEARCHERS: Mark Larson, Eric Zahl, John

 Dunford, and Jeff Johnson

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Underground

mining, ground stability, ground

fall, horizontal stress, numerical

modeling, coal bump, rock joint

BIBLIOGRAPHY

Brady T, Johnson J, Pariseau B,

Stahl M, Whyatt [2000]. Timedependent rock mass motion at

the Homestake Mine, Lead, SD. 

Presentation at SME annual

meeting (Salt Lake City, UT,

February 29-March 1), paper

00-40. Littleton, CO: Society for

Mining, Metallurgy, and

Exploration, Inc.

Larson M, Wade R [2000]. 

Creep along weak planes in roof

and how it affects stability. 

Presentation at SME annual

meeting (Salt Lake City, UT,

February 29-March 1), paper

00-130. Littleton, CO: Society

for Mining, Metallurgy, and

Exploration, Inc.

Zahl E, Dunford JP, Schissler A,

Larson MK, Pierce PA, Jones

FM [2000]. Development of

stress measurement techniques

in bump-prone coal for safety

decisions. In: Peng SS, Mark C,

eds. Proceedings of the 19th

International Conference on

Ground Control in Mining. 

Morgantown, WV: West

Virginia University, pp. 101-111.

PURPOSE: Develop and integrate new computer modeling and field

measurement techniques to assess rock mass properties and the stability of

underground workings more accurately over time. Develop indicators to

allow miners to assess the immediate stability of their working environment.

RESEARCH SUMMARY: Mine Safety and Health Administration

statistics for 1994-98 show that 47% of the mine fatalities and 16% of the

mine injuries in underground mines were attributable to ground falls. Loss

of ground stability, either locally or across large sections of a mine, is a

serious problem for the mining industry. This project seeks to develop

better geotechnical, monitoring, and modeling tools so mining companies and

consultants may design and operate more stable underground mines,

thereby reducing the fatality and injury rates of underground miners.

Research efforts involve field studies and evaluations, laboratory

investigations, property measurements, and computer modeling studies. In

the field, a stress monitoring system is being developed to monitor stress

changes during mining. This system is being evaluated for its potential to

predict imminent coal bumps. Methods of conveying measurement

information to engineers, foreman, and miners and gathering feedback are

being developed and improved. The stress monitoring system is being

adapted to solve other stability concerns.

In another research task, the role of rock joints in the stability of drifts

and stopes is being studied. In the laboratory, a series of direct shear tests

have been completed on jointed mudstone from a coal mine to determine

friction and creep properties to be used to look at various failure

mechanisms. This same series of tests will be done on core obtained from

a platinum-palladium mine. Computer models are being used to understand

the effects of high topographical relief on ground stability at a coal mine, as

well as how joints affect rock mass stability. 

By taking this approach through state-of-the-art field, laboratory, and

computer modeling studies, ground failure mechanisms will be better

understood so that accidents resulting from ground falls may be prevented

or reduced in number.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 43

RMSS cable and read-out box.

BIBLIOGRAPHY

Marshall TE, Prosser LJ Jr.,

Iannacchione AT, Dunn M

[2000]. Roof monitoring in

limestone mines: experience

with the roof monitoring safety

system (RMSS). In: Peng SS,

eds. Proceedings of the 19th

International Conference on

Ground Control in Mining. 

Morgantown, WV: West

Virginia University, pp. 185-191.

NIOSH [2000]. Technology

news 481: Update—roof

monitoring safety system for

underground stone mines. 

Pittsburgh, PA: U.S.

Department of Health and

Human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute for

Occupational Safety and Health.

REDUCING GROUND FALLS IN UNDERGROUND STONE AND NONMETAL MINES

RESEARCHERS: L.J. Prosser, Jr., and Roy H. 

 Grau III

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

(412) 386-5010

PURPOSE: Improve mine worker safety in underground

stone and nonmetal mines by using a combination of communication/

surveillance, safety research engineering , and technology transfer

activities.

RESEARCH SUMMARY: Roof and rib falls are a constant potential

hazard to underground mine workers. Falls of ground can cause fatalities

and typically result in severe injuries. Measuring and detecting roof rock

movements provide a starting point in understanding roof behavior and can

be indicators of mine conditions.

The stresses on a mine roof can be from vertical or horizontal forces. 

Horizontal stresses affect large spans of mine roof rock and often cause

large roof falls. An estimated 25% to 35% of the underground stone

industry is subjected to horizontal stresses. To address the unstable roof

conditions resulting from high horizontal stresses, an experiment is

underway to determine if changing the direction of mining and the size and

spacing of the pillars can lessen the adverse affects of horizontal stress.

At a mine in southwestern Pennsylvania, an array of microseismic

instruments is recording the “noise” levels of rock as mining proceeds in

two different directions. A broad simplification of the concept behind this

work is that if the direction of the horizontal stress is perpendicular to the

direction of mining, less “noise” will be measured from the rock at and

above the roof line. It is believed that the amount and intensity of the rock

noise is related to the amount and intensity of rock failure; therefore, the

mine layout that produces the least noise will be the safest. In addition,

because most underground stone is mined using rooms and pillars of

approximately the same dimensions, elongated and staggered pillars may

also lessen damage to the roof.

Another instrument used in an attempts to determine roof behavior is

the NIOSH-developed Roof Monitoring Safety System (RMSS). The

RMSS provides the capability to measure roof movements through insertion

into a borehole in the mine roof. Since its inception in 1998, more than a

dozen operations have used this instrument. The RMSS is intended for use

in a comprehensive ground control program. Visual inspections of geologic

conditions, along with recording of other physical conditions and tracking

roof movement, help to maintain a safer mine environment.
Spokane and Pittsburgh Research Laboratories

44 Office for Mine Safety and Health Research

Rib failure at an underground gold mine in Nevada.

REDUCING GROUND FALL HAZARDS IN

NEVADA UNDERGROUND MINES

RESEARCHERS: Brian White, Brad Seymour, 

 Lewis Martin, and Doug Tesarik

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Ground fall

hazards, Nevada underground

gold mines, mining in weak rock

BIBLIOGRAPY 

Seymour JB, Tesarik DR,

McKibbin RW, Jones FM

[1999]. Monitoring mininginduced stress changes with the

biaxial stressmeter. In: Leung

CF, Tan SA, Phoon KK, eds. 

Field Measurements in

Geomechanics. Proceedings of

the Fifth International

Symposium on Field Measureents in Geomechanics

(Singapore, December 1-3). 

Rotterdam: Balkema, pp. 55-60.

Tesarik DR, Seymour JB,

Yanske T [1999]. Long-term

stability of a backfilled roomand-pillar mine. In Leung CF,

Tan SA, Phoon KK, eds. Field

Measurements in

Geomechanics. Proceedings of

the 5th Inter-national

Symposium on Field

Measurements in Geomechanics

(Singapore, December 1-3). 

Rotterdam: Balkema, pp. 431-

435.

PURPOSE: Identify, describe, and quantify ground and

backfill response to mining, conditions that contribute to

ground falls, and practices that reduce ground fall risks.

RESEARCH SUMMARY: The discovery of extensive,

high-grade gold deposits at depth in Nevada has led to an

increase in new underground operations that is likely to

continue for decades to come. The large size and irregular

shapes of the ore zones and the pervasive alteration and extensive

fracturing that characterize these gold deposits makes the ground weak and

vulnerable to unplanned collapses. Ground failures on all scales are major

hazards, with at least one mine reporting five major cave-ins within ore

zones and another indicating numerous falls of ground involving rock failure

beyond rock bolt anchorages. During 1990-99, injuries from falls of ground

exceeded injuries in all other categories in all years except one. Seven

ground-fall-related fatalities occurred during this period, six of them since

1995. As mines become deeper and mining more extensive, the potential

for small- and large-scale catastrophic failures is likely to increase greatly.

This new project is an interdisciplinary investigation involving experts in

the fields of geology, backfill, load and strain instruments and

measurements, physical property investigations, and modeling. Field

measurements will be analyzed within a geologic perspective that

incorporates local lithology, structure, and rock alteration. Modeling of

stress and strain in host rock, ore, and backfill will incorporate localized and

large-scale geologic and physical property data obtained in the lab and in the

field. 

Interaction between filled and unfilled mine openings and ore and wall

rock will be investigated on various scales. Such studies will include elastic,

brittle, and time-dependent displacements; their effects on mine openings;

and the response of backfill and other ground support to loading. 

Experience gained from ongoing cooperative research with underground

mines in other States will be used to supplement backfill and ground support

investigations for the weak ground conditions in Nevada.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 45

Rock burst damage in a hard-rock mine.

IDENTIFICATION AND CONTROL OF ROCK

BURST HAZARDS

RESEARCHERS: Jeffrey K. Whyatt, Brian G.

 White, and Theodore J. Williams

AFFILIATION: Spokane Research Laboratory 

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Ground

control, rock bursts, in situ

stress, geology

BIBLIOGRAPHY 

White BG, Whyatt JK [1999]. 

Role of fault slip on mechanisms

of rock burst damage, Lucky

Friday Mine, Idaho, USA. In:

Hagen TO, ed. SARES 99:

Second Southern African Rock

Engineering Symposium. 

Implementing Rock Engineering

Knowledge (Johannesburg,

Republic of South Africa,

September 13-15). Int Soc

Rock Mechanics, pp. 169-178.

White B, Whyatt JK [2000]. 

Ground instabilities in underhand

stopes resulting from bedding

plane slip in wall rock, Lucky

Friday Mine, Coeur d’Alene

District, Idaho. Presentation at

SME annual meeting, Salt Lake

City, UT, February 29-March 1.

Whyatt JK, Williams TJ, White

BG [2000]. Ground conditions

and the May 13, 1994, rock

burst, Coeur d’Alene Mining

District, northern Idaho. In:

Girard J et al., eds. Pacific

Rocks 2000. Rock Around the

Rim: Proceedings of the Fourth

North American Rock

Mechanics Symposium

(NARMS 2000) (Seattle WA,

July 31-August 3). Rotterdam: 

Balkema, pp. 313-318.

PURPOSE: Increase miner safety by identifying geologic

features that contribute to the risk of rock bursts and linking

these features to specific rock burst mechanisms.

RESEARCH SUMMARY: Rock bursts pose a serious hazard to miners

throughout the world even after a century of research. In places where

rock bursts of a similar type recur, countermeasures have been developed

and employed that improve miner safety. However, these countermeasures

must be appropriate to local geologic conditions and rock burst mechanisms

to be effective. 

The geologic environment of many ore deposits is very complex. An

unexpected change in geology can trigger a rock burst where it would not

be expected and result in injuries or fatalities. Researchers are seeking to

identify those few features most likely to contribute to rock bursting and link

them to specific rock burst mechanisms and relative levels of rock burst

risk. Topics of particular interest include natural stress concentrations

developed through tectonic processes and the association of particular types

of altered rock with residual stress. Appropriate protection measures are

also being studied. Currently, project studies are focused on mines in the

Coeur d’Alene Mining District of northern Idaho, but will also address rock

burst hazards in other deep metal mines in the United States.

The discovery that silicification, which is the alteration of rock by silicabearing faults emanating from quartz veins, appears to be a marker of

significantly increased levels of rock strength, rock brittleness, and in situ

stress levels. A method for modeling concentrations of gravitational,

tectonic, and residual stresses in various geologic features is being

developed and used to study variation in rock burst hazards in the Coeur

d’Alene district.
Spokane and Pittsburgh Research Laboratories

46 Office for Mine Safety and Health Research

Catastrophic slope failure in a surface mine.

SLOPE STABILITY HAZARD RECOGNITION

FOR METAL/NONMETAL MINES

RESEARCHERS: Jami M. Girard and Ed McHugh

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Highwall, slope

stability, open pit, remote

sensing, monitoring, rock

mechanics, bench, software

BIBLIOGRAPHY

Girard JM, McHugh E [2000]. 

Detecting problems with mine

slope stability. Presentation at

31st Annual Institute on Mine

Safety and Health Research 

(Roanoke, VA, August 27-30).

McHugh E, Girard JM, Sabine

C [2000]. Current research on

slope movement in mines: use of

hyperspectral imagery and

interferometric radar. In:

Proceedings of the 14th

International Conference and

Workshops, Applied Geologic

Remote Sensing (Las Vegas,

NV, November 6-8).

Miller S, Girard JM, McHugh E

[2000]. Computer modeling of

catch benches to mitigate

rockfall hazards in open pit

mines. In: Girard J et al., eds. 

Pacific Rocks 2000. Rock

Around the Rim: Proceedings of

the Fourth North American

Rock Mechanics Symposium

(NARMS 2000) (Seattle WA,

July 31-August 3). Rotterdam:

Balkema, pp. 539-545.

PURPOSE: Minimize hazards associated with unstable

mine slopes through an aggressive research approach

involving engineering controls, advanced monitoring

equipment, geotechnical design, and computer models.

RESEARCH SUMMARY: Whether underground or on the surface,

unanticipated rock movements create the potential for a mine catastrophe. 

A review of Mine Safety and Health Administration statistics from 1995

through the second quarter of 2000 revealed that 33 workers were killed in

slope-failure-related accidents.

Open-pit mines are deeper than ever before, and the mechanics of rock

mass strength and rock mass movement at large scales is poorly

understood. However, even shallow strip mines and quarries can

experience devastating consequences from slope failure.

This project addresses three major areas.

(1) Slope monitoring systems. The effectiveness and limitations of

current slope monitoring and warning systems are being evaluated. A

handbook for the mining industry is being developed to teach mine personnel

about the proper use and placement of instruments and the limitations of

various warning systems. Field tests of state-of-the-art equipment are also

scheduled. 

(2) Geotechnical design. Beta version software has been developed

to estimate probable failure volumes on catch benches. Geotechnical

engineers will be able to use this software to determine whether benches

are designed wide enough to keep rock from falling to the working surface

below. Several training courses related to software use and release of the

final version are scheduled.

(3) Engineering forensics and risk analysis. Research analysis of

documented failures will be used to identify root causes. New methods for

computer modeling of rock mass behavior, pore pressure effects, and other

tools will be studied. Input into a preliminary risk analysis model will also be

collected.

Better design and control of slopes will reduce the number of fatalities

and injuries. Results of this research can be transferred to a number of

other civil and geotechnical engineering problems, including landslide

control, design of roadcuts, railroads, canals, refuse disposal sites, and earth

dams.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 47

Safety performance testing of an innovative timber

support in the Mine Roof Simulator.

DEVELOPMENT AND EVALUATION

OF INNOVATIVE ROOF SUPPORT

TECHNOLOGIES

RESEARCHER: Thomas M. Barczak

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Coal mining,

roof support, underground

mining, emerging technologies

BIBLIOGRAPHY

Barczak TM [2000]. Optimizing

secondary roof support with the

NIOSH Support Technology

Optimization Program (STOP). 

In: New Technology for Coal

Mine Roof Support. Pittsburgh,

PA: U.S. Department of Health

and Human Services, Public

Health Service, Centers for

Disease Control and Prevention,

National Institute for

Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 2000-151, IC 9453.

Barczak TM, Mucho TP,

Dolinar DR, Bower J, Bryja J

[1999]. Longwall tailgate

support: consideration, design,

and experience. In:

Proceedings of Longwall USA

International Exhibition &

Conference,

pp. 79-104.

PURPOSE: Facilitate the development of new roof

support technologies through industry partnerships with

various support manufacturers and ensure that these new

support technologies meet basic safety standards before

they are commercialized for use in underground mines.

RESEARCH SUMMARY: This project began in FY2000 and is planned

to continue for at least the next 5 years as new support technologies are

developed for improving ground control in underground mines.

Ground control is a fundamental aspect of all underground mining. 

Historically, 30% to 40% of the fatalities in underground mines are caused

by unstable roof rock falling in on the miner, and this percentage has been

increasing in recent years. Roof support systems are routinely installed in

all mines in an effort to prevent these catastrophic roof falls from occurring. 

While these supports are necessary to prevent roof falls from occurring, the

material handling requirements for the construction of these supports is

another major source of injury to mine workers. Surveillance data show

that there are approximately 4,500 lost workdays per year in coal mines

alone due to material handling injuries associated with roof support

construction. Because of the importance of ground control, roof support

manufacturers continually strive to develop new roof support technologies

that provide superior ground control at less cost.

Our goal is to ensure that new support technologies are properly

designed to ensure the safety of mine workers. Through a cooperative

program with various support manufacturers, each new support technology

is rigorously tested in NIOSH's unique Mine Roof Simulator. During the

development of a new support system, this testing identifies design

deficiencies so that they can be corrected early. Once the support system

satisfactorily passes this testing protocol, the performance characteristics

and its limitations are determined in order to optimize the safe use of this

support in the mine.

Sixteen new support technologies have been successfully developed and

implemented into mines throughout the world during the past 5 years. Using

the database of support safety performance testing, a software program

(Support Technology Optimization Program (STOP)) was recently

developed to optimize the design and use of these new support technologies.
Spokane and Pittsburgh Research Laboratories

48 Office for Mine Safety and Health Research

Monitoring the operation of an underground

microseismic network.

COAL BUMP REDUCTION THROUGH

ADVANCED MINE DESIGN

RESEARCHER: John L. Ellenberger

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Bumps,

bounces, coal mine, ground

control, rock mechanics

BIBLIOGRAPHY

Ellenberger JL, Heasley KA

[2000]. Coal mine seismicity

and bumps: historical case

studies and current field activity. 

In Peng SS, Mark C, eds. 

Proceedings of the 19th

International Conference on

Ground Control in Mining. 

Morgantown, WV: West

Virginia University, pp. 112-120.

Heasley, KA [2000]. The

forgotten denominator: pillar

loading. In: Girard J,

Liebman M, Breeds C, Doe T,

eds. Pacific Rocks 2000;

Proceedings of the Fourth North

American Rock Mechanics

Symposium. Alexandria, VA:

American Rock Mechanics

Association, pp. 457-464.

Mark C, Heasley KA,

Iannacchione AT, Tuchman RJ,

eds. [1999]. Proceedings of the

Second International Workshop

on Coal Pillar Mechanics and

Design. Pittsburgh, PA: U.S.

Department of Health and

Human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute for Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 99-114, IC 9448.

PURPOSE: Reduce the injuries and fatalities caused by

coal bumps through the development of improved coal mine

design concepts.

RESEARCH SUMMARY: Coal bumps are the sudden,

violent expulsion of coal from a pillar or rib into an adjacent

entry and related strain-energy release. On average, in the United States

two coal miners are seriously injured every year and a miner is killed every

other year because of coal bumps. In general, the exact mechanics of coal

bumps are still not completely understood. It is believed that this lack of

fundamental knowledge is the primary hindrance to further bump mitigation.

The basic research approach of this project is to instrument a deep,

bump-prone longwall mine and determine the main roof, gob (broken rock),

and floor behavior using a real-time microseismic system. This

microseismic system “listens” to the rock and determines the timing and

location of the failure of the rock strata surrounding the longwall. By

analyzing the observed rock failure, researchers can better understand the

caving of the massive main roof, the compaction and load acquisition of the

gob, the failure of the floor, and the stress redistribution in the coalbed and

surrounding strata. With this additional knowledge, mines can be better

designed to reduce dangerous bump occurrences.

Throughout the first 3 years of this project, a microseismic system was

installed at a deep coal mine in Utah (in cooperation with the coal mine, the

University of Utah, the Virginia Polytechnic Institute and State University,

and several contractors), and one entire panel was monitored. The system

consists of 24 geophones (microphones for listening to the rock) surrounding

the coal mine on the surface and underground. At the mine office, a data

analysis workstation receives, processes, and stores the data from the

geophones. Future data analysis will determine the exact nature of the

massive overburden failure. An appropriate mechanistic model (beam

theory, plate theory, discrete-element, finite-element, boundary-element,

etc.) will then be used to simulate and approximate the observed behavior

for pursuing improved bump-proof mine designs.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 49

Cables connect sensitive seismometers to an

underground networked data acquisition computer.

GROUND STABILITY ASSESSMENT WITH

SEISMIC MONITORING

RESEARCHER: Peter Swanson

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Rock bursts,

coal bumps, mine collapse,

mining-induced seismicity, rock

mechanics

BIBLIOGRAPHY

Swanson P [2000]. AutomatedPC-networked-based seismic

monitoring systems applied to

mining hazards research. 

Seismol Res Let 71(1):234.

Zipf RK Jr., Swanson PL

[1999]. Description of a large

catastrophic failure in a

Wyoming trona mine. In:

Amadei B et al. eds. Rock

Mechanics for Industry. 

Proceedings of the 37th U.S.

Rock Mechanics Symposium

(Vail, CO, June 6-9). 

Rotterdam: Balkema, pp. 293-

298.

PURPOSE: Develop and apply seismic monitoring tools

to aid in estimating and forecasting ground control hazards

resulting from uncontrolled or unplanned deformation of the local ground

surrounding underground openings.

RESEARCH SUMMARY: Rock bursts, coal bumps, roof falls, and largescale collapses represent serious ground control problems facing miners in

certain industry sectors. These low-probability, high-consequence events

often result in severe injuries or death and can affect an entire underground

workforce. An inability to address these problems effectively can result in

resource abandonment and/or mine closure and cause a significant

economic impact on entire communities.

Project objectives are to (1) develop inexpensive automated seismic

monitoring technology for use in reducing mine worker exposure to

catastrophic ground hazards and emergency response time, (2) transfer the

technology to mine operators, mining organizations, and consultancy groups,

and (3) apply this technology in NIOSH studies seeking to reduce or

eliminate these hazards.

A user-friendly, PC-network-based, automated seismicity monitoring

system is under development. The first prototype system was initiated in a

joint project with Silver Valley Resources, Inc., at the Galena Mine in

Wallace, ID. By developing the technology at a low cost, NIOSH can

employ several systems in different mine safety research studies and, at the

same time, encourage industry adoption as a safety tool in daily operations. 

Hardware and software development continue with an emphasis on shifting

the placement of instruments from the harsh underground environment to

the more readily accessible surface. NIOSH seismic monitoring networks

are currently in operation with industry partners in deep metal, coal, trona,

and limestone mines to address problems of rock bursts, coal bumps, mine

collapses, and roof falls.
Spokane and Pittsburgh Research Laboratories

50 Office for Mine Safety and Health Research

Cohesive forces and

particle velocity

vectors in a

simulated ore pass.

DESIGN OF MINE ORE PASSES

RESEARCHERS: Michael Beus, Bill Stewart, 

and Steve Iverson

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Ore pass,

particle flow, dynamic loads,

hangups

BIBLIOGRAPHY

NIOSH [2000]. 

TECHNOLOGY NEWS 479:

Ore pass level and blockage

locator device. Spokane, WA:

U.S. Department of Health and

Human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute for

Occupational Safety and Health.

Scott V, Drescher A, Iverson S,

Beus M [2000]. Static and

dynamic loads in a scaled ore

pass. In: Girard J et al., eds. 

Pacific Rocks 2000. Rock

Around the Rim: Proceedings of

the Fourth North American

Rock Mechanics Symposium

(NARMS 2000) (Seattle WA,

July 31-August 3). Rotterdam:

Balkema, pp. 381-386.

PURPOSE: Improve ore pass safety and design criteria to

prevent hangups and structural failures.

RESEARCH SUMMARY: Recent accidents have

underlined the lack of ore pass designs and standards

available to both mine engineers and Mine Safety and Health

Administration (MSHA) enforcement staff. This project will

focus on ore pass design, ore and waste hangup

 prevention, and safe procedures for removing hangups.

Based on accident investigations, review of MSHA data, and hazard

and fault tree analyses, several areas of research were identified that could

lead to reducing ore pass hazards. These topics are—

• Static and dynamic loading of ore pass chutes and gates.

• Prevention of hangups of material in ore passes.

• Development of a field-ready, ore pass load measurement system. 

Both physical and computer models are being used to validate computer

codes. Design and construction of a reduced-scale test facility of an actual

ore pass and chute and gate assembly have been completed for static and

dynamic load tests. These tests will validate strategies for obtaining static

and dynamic response to varying loads in an actual ore pass. Work is

underway to determine the role of moisture content, the fine grain-size

fraction, and stop-and-go ore movement on cohesive-type hangups. 

Computer models using two- and three-dimensional particle flow programs

will be continued to predict particle flow and hangups. Special tests will be

conducted to determine stiffness characteristics and damping coefficients of 

mine material. These data will be used as input to the models for more

accurate predictions of particle flow. Various designs of ore pass

structures will be simulated in the models.

Improved ore pass safety and design criteria will prevent hangups and

structural failures. Newly developed particle flow computer programs

might also be applied to analyzing construction code design standards.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 51

Haulage vehicle fire.

FIRES, EXPLOSIONS, AND

VENTILATION

CONTROL AND SUPPRESSION OF MINE

FIRES

RESEARCHERS: Alex C. Smith and 

 Charles P. Lazzara, Ph.D.

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Mine fires,

suppression, extinguishment,

flammability, water mist

BIBLIOGRAPHY

Smith AC, Lazzara CP [1998]. 

Water mist suppression of fires

in underground diesel fuel

storage areas [Abstract]. In:

Beall KA, ed. Annual

Conference on Fire Research -

Book of Abstracts. 

Gaithersburg, MD: U.S.

Department of Commerce,

Technology Administration,

National Institute of Standards

and Technology, pp. 111-112.

PURPOSE: Enhance the safety of mine workers by increasing the mining

industry’s ability to control and extinguish fires through the development of

new and improved fire suppression systems.

RESEARCH SUMMARY: Although the number of fires and fire injuries

is relatively low for underground mining, fires that occur in confined spaces

have potentially catastrophic consequences. Federal regulations require

mine operators to take measures to prevent fires in underground mines. 

However, fires still occur because of the misuse of materials, spontaneous

combustion, conveyor belt equipment malfunction, electrical arcing,

overheating of equipment, and other causes. Fires on large surface vehicles

can erupt rapidly via ignition of fuel, lubricating fluids, or hydraulic fluids. 

The fires can spread rapidly to other parts of the vehicle, such as the large

rubber tires, endangering the lives of the operators. Egress from such

vehicles is often awkward and time-consuming, thereby necessitating the

need for fire protection systems.

This project focuses on three tasks. The first evaluates the application

of new and improved fire suppression systems to protect underground mine

haulageways and stationary equipment. Full-scale experiments are being

conducted in the Lake Lynn Laboratory fire suppression facility to

determine the effectiveness of water mist systems for extinguishing air

compressor fires. The second task assesses the flammability hazards of

selected noise control materials that are being introduced into the mining

environment under realistic, end-use conditions. The results may be

applicable to the development of new or modified laboratory-scale fire tests

for fire-resistant noise control materials used in mines. The third task

determines the intrinsic causes of large surface vehicle and surface

equipment fires. The results are used to recommend new or improved

types of fire detection and/or suppression systems for these vehicles and

equipment. These tasks are being done in collaboration with the Mine

Safety and Health Administration and the mining industry.
Spokane and Pittsburgh Research Laboratories

52 Office for Mine Safety and Health Research

Testing of sealant strength across concrete block joint.

IMPROVING CFR SAFETY EVALUATIONS

FOR MINE VENTILATION SEALS AND

STOPPINGS

RESEARCHER: Thomas M. Barczak

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Coal mining,

Code of Federal Regulations,

mine ventilation stoppings, mine

seals, ASTM E-72

BIBLIOGRAPHY

Baker LR [1980]. Lateral

loading of masonry panels:

structural design of masonry. 

Sydney, Australia: Cement and

Concrete Association.

Cox FW, Ennenga JL [1958]. 

Transverse strength of concrete

block walls. ACI J 54:951-960.

PURPOSE: Provide a safer environment and reduce material handling

injuries for mine workers by developing alternative safety evaluation

requirements for mine ventilation stoppings and seals that more realistically

simulate actual mine conditions. Examine emerging lightweight material

technologies that currently fail existing regulatory statutes.

RESEARCH SUMMARY: This project is in its second year. The initial

phase of full-scale testing to determine the impact of restraint and preload

on dry-stacked block constructions has verified that the transverse loading

capability of these structures is greatly improved by the restraint provided

by the mine roof and floor and the addition of preload at the completion of

the wall construction. The systematic series of full-scale laboratory tests in

NIOSH’s unique Mine Roof Simulator is to continue during the next year

with various block designs to determine a quantitative relationship between

these parameters. Failure mechanisms show that the shear strength and

compressive strength of the block are important parameters that determine

the loading capability of these structures, but these parameters are ignored

in the current Code of Federal Regulations. Part of this effort is to define

new criteria to account for these deficiencies and, by doing so, provide

more insurance against premature failure of these critical structures.

Several lightweight block technologies have been identified for

examination as replacement to conventional mortar blocks used for stopping

construction. Five different lightweight block units weighing up to 50% less

than the conventional block have been chosen for analysis. Using the

NIOSH-revised lifting equation, these lightweight blocks are within the

recommended lifting thresholds for this type of activity. As such, they are

expected to significantly reduce musculoskeletal repetitive trauma disorders

and other material handling injuries associated with stopping wall

construction in underground mines.

An underground study of one of the lightweight block technologies is

underway at a Consol Energy mine. Two walls constructed from these

lightweight blocks are being instrumented to measure the loading and

convergence and are being compared to two instrumented walls

constructed from conventional mortar block. The goal of this study is to

provide baseline loading data and compare the response of the two

materials, as well as provide information on the loading conditions that can

be incorporated into the laboratory testing protocols used in the Mine Roof

Simulator.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 53

Remains of standard seal destroyed by methane-airoxygen explosion.

HYDROSTATIC EVALUATION OF MINE SEALS

RESEARCHERS: Michael J. Sapko and Eric S.

Weiss

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Mine

ventilation seals, water

inundation, explosions

BIBLIOGRAPHY

Sapko MJ, Weiss ES,

Cashdollar KL, Greninger NB

[1999]. Overview of NIOSH’s

mine seal research. In:

Proceedings of the 28th

International Conference of

Safety in Mines Research

Institutes (Sinaia, Romania). 

Vol. I, pp. 71-85.

Sapko MJ, Weiss ES, Greninger

NB [1999]. Recent mine seal

research conducted by NIOSH. 

In: Proceedings of the PolishAmerican Seminar on Seals and

Barriers as a Means of

Protection Against Fires and

Explosions in Mines (Katowice,

Poland, May 27-28, 1999).

PURPOSE: Develop improved apparatus and methodologies

to better characterize strength properties of mine seals;

evaluate equivalence of hydrostatic, pneumatic, and explosion

testing of seals; and identify models for possible use by the Mine Safety and

Health Administration (MSHA) in approval actions regarding seals.

RESEARCH SUMMARY: Seals are used extensively in mining to isolate

worked-out areas of a mine, contain active fire zones, and control water

inundations, thereby protecting miners from these life-threatening hazards. 

Seals, along with generalized rock dusting, are the last line of defense

against underground explosions in U.S. coal mines. MSHA has a

compelling need to evaluate geometric scaling criteria for seals, alternative

designs for high-convergence conditions, and adverse geologic conditions

such as friable adjacent strata. No single seal design is suitable for all

possible scenarios. Some seals must withstand excessive convergence,

some require quick curing, some require special anchoring because of the

adjacent strata conditions, some need to resist attack by acid mine water,

some are needed for very wide or high roadways, some need to hold back

water, some need steel reinforcement and high-strength cement, some need

fire traps, some need a low gas leakage rate, and some must perform for

years. In the past, seals were evaluated in full-scale mine explosion tests,

an expensive and time-consuming task, or were not evaluated at all because

there was no practical, reliable testing methodology available.

Constant volume explosion studies continue in both the standard

(2,500-ft3) and large (6,800-ft3) explosion test chambers at Lake Lynn

laboratory. The seals are subjected to various explosion pressure histories

produced by the combustion of mixtures of methane, nitrogen, and oxygen. 

Seal flexure and ultimate failure conditions are measured as a function of

pressure loading. A major effort in FY01 is to evaluate seals of different

cross-sectional areas. Cost-sharing research is to continue in FY01 with

important collaboration between NIOSH, the mining industry, and seal

manufacturers. Results from such tests provide valuable information

applicable to the on-site evaluation of new mine seals and the development

of size-scaling relationships and design safety factors.
Spokane and Pittsburgh Research Laboratories

54 Office for Mine Safety and Health Research

A researcher checks the cellular telephone data

transmission components of the Remote Gob Gas

Venthole Data Acquisition and Transmission System.

CHARACTERIZATION AND MITIGATION

OF MINE GAS EMISSIONS

RESEARCHER: William P. Diamond

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Coal mining,

mine safety, methane

explosions, control technology,

methane drainage

BIBLIOGRAPHY

Diamond WP, Garcia F [1999]. 

Prediction of longwall methane

emissions: an evaluation of the

influence of mining practices on

gas emissions and methane

control systems. Pittsburgh,

PA: U.S. Department of Health

and Human Services, Public

Health Service, Centers for

Disease Control and Prevention,

National Institute for

Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 99-150, RI 9649.

Diamond WP, Mucho TP,

Garcia F, Jeran PW, LaScola

JC, McCall FE, et al. [1999]. 

NIOSH longwall gob gas flow

characterization studies:

Pittsburgh coalbed, PA. In:

Proceedings of Longwall USA

International Exhibition &

Conference, pp. 105-118.

Mucho TP, Diamond WP,

Garcia F, Byars JD, Cario SL

[2000]. Implications of recent

NIOSH tracer gas studies on

bleeder and gob gas ventilation

design. SME preprint 00-8. 

Littleton, CO: Society for

Mining, Metallurgy, and

Exploration, Inc.

PURPOSE: Develop optimized longwall methane control

systems and strategies to reduce the risk of catastrophic

explosions and fires in the underground workplace.

RESEARCH SUMMARY: An increased risk of

explosions in underground mines can be the direct result of excessive

methane emissions. Methane emission rates are often unpredictable

because the interactions between geology, mining, ventilation, and methane

control systems vary considerably due to site-specific conditions and mining

practices. The focus of this research has been increased methane

emissions associated with longwall gobs resulting from emerging

technologies that facilitate the mining of increasingly larger dimension

longwall panels in U.S. coal mines. This project is nearing completion of its

investigation of the factors controlling gas emissions from longwall gobs and

the development and/or optimization of control technologies.

Due to the variability of the multiple factors controlling gas emissions

associated with longwall mining, both mine-site field characterization studies

and theoretical modeling studies are necessary to address the research

problem. The longwall gob gas flow characterization field studies use

controlled releases of a tracer gas into the mine ventilation and methane

control systems to identify methane gas flow paths and associated flow

characteristics. These studies are being conducted at a RAG American

Coal Co. mine in close coordination with organized labor (United Mine

Workers of America) and State and Federal regulatory authorities (the

Pennsylvania Bureau of Deep Mine Safety and the Mine Safety and Health

Administration). Selected optimized methane control strategies developed

from the preliminary results of the field studies are being implemented at the

study mine and at an adjoining mine. The results of this final phase of the

field studies and the gob gas flow theoretical modeling are to be used to

refine the best practices for longwall gob gas control. These best practices

include information on optimized placement of gob gas ventholes and

operational efficiencies, including a state-of-the-art monitoring and data

transmission system based on cellular telephone technology to provide realtime performance data from remote gob gas venthole locations.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 55

Explosive charge set up for the air gap test. This test

evaluates the ability of the detonation of a permissible

explosive to jump a gap in the explosive column.

EXPLOSIVES HAZARD SURVEILLANCE 

AND EVALUATION FOR THE MINE SAFETY

AND HEALTH ADMINISTRATION

RESEARCHER: Cynthia A. Mytrysak

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Permissible,

explosive, blasting

BIBLIOGRAPHY

30 CFR 15, Requirements for

Approval of Explosives and

Sheathed Explosive Units.

PURPOSE: Provide technical assistance to the Mine

Safety and Health Administration (MSHA) in the testing

of new candidate permissible explosives, explosive

accident investigations, and in conducting research on other explosive

hazards.

RESEARCH SUMMARY: The tasks of this project are to (1) test

new candidate permissible explosives for use in underground mining for

MSHA based on requirements detailed in 30 CFR 15, (2) assist MSHA

in explosives accident investigations, including the testing of explosives

involved in the accidents, and (3) conduct research on explosive hazards

revealed during the course of accident investigations. The goal is to

develop engineering solutions to help prevent future injuries and fatalities.

Research was completed on a detonator/booster assembly that was

involved in a recent fatal incident. Indications were that a

detonator/booster assembly fell into a borehole and exploded prematurely

when it hit another booster already in the hole. This particular type of

explosive had been involved in two other incidents (one fatal) in recent

years. Cooperative research with the manufacturer and MSHA is

continuing in an effort to find reliable, practical ways to prevent such

incidents in the future.
Spokane and Pittsburgh Research Laboratories

56 Office for Mine Safety and Health Research

Frictional test apparatus showing ignition of methane-air.

EXPLOSION HAZARDS REDUCTION

RESEARCHERS: Kenneth L. Cashdollar,

Michael J. Sapko, and 

Issac A. Zlochower, Ph.D.

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Explosions,

prevention, mining

BIBLIOGRAPHY

Cashdollar KL [2000]. 

Overview of dust explosibility

characteristics. J Loss Prev

Process Indus 13:183-199.

Cashdollar KL, Zlochower IA,

Green GM, Thomas RA,

Hertzberg M [2000].

Flammability of methane,

propane, and hydrogen gases.

J Loss Prev Process Indus

13:327-340.

Sapko MJ, Weiss ES,

Cashdollar KL, Zlochower IA

[2000]. Experimental mine and

laboratory dust explosion

research at NIOSH. J Loss

Prev Process Indus 13:229-242.

PURPOSE: Reduce explosion hazards in mining through

basic and applied research on the prevention and

suppression of gas and/or dust explosions.

RESEARCH SUMMARY: Explosions in coal mines are due to accumulations of coal dust and/or methane gas. The ignition of such flammable

materials can develop into a major disaster, such as the recent explosion at

a Utah mine, which resulted in two fatalities. Explosions can be prevented

or mitigated by minimizing methane concentrations through ventilation and

drainage, by adding sufficient rock dust to inert the coal dust, by eliminating

ignition sources, by using passive and active barriers to suppress

propagating explosions, and by using high-strength seals to prevent gob

explosions from propagating into working areas of the mine. Research into

the causes and mechanisms of gas and dust explosions is needed to develop

techniques and strategies for explosion prevention and suppression in

underground mines and in aboveground processing plants. Assistance is

also provided to the Mine Safety and Health Administration (MSHA) in the

forensic investigation of mine accidents. Research on frictional ignitions

includes experimental studies and surveillance in commercial mines. 

Intermediate-scale experimental research is being conducted on the relative

incendivity of sandstone, metal, etc., for igniting methane gas and

hydrocarbon oils from mines. Additional research on frictional ignitions is

being conducted in the 20-liter explosibility chamber through measurements

of the hot-spot temperature and surface area necessary to ignite flammable

gases, vapors from oil, and dust mixtures with air. Close cooperation with

the mining industry, MSHA, and the United Mine Workers of America is

expected.

Continuing basic experimental research includes large-scale coal dust

explosion studies conducted at the Lake Lynn Experimental Mine and

explosion studies conducted in the 20-liter chamber. These experiments are

conducted to better understand coal dust combustion mechanisms to aid in

the development of explosion prevention and suppression techniques. This

basic explosion research is conducted in conjunction with laboratory

research at universities and private laboratories.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 57

Modified spray system used with scrubber.

EXTENDED-CUT AIR DELIVERY SYSTEMS

RESEARCHER: Charles D. Taylor

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Hazard

identification, prevention, exposure assessment, underground

mining, methane

BIBLIOGRAPHY

Taylor CD, Thimons ED,

Zimmer JA [1999]. Comparison

of methane concentrations at a

simulated coal mine face during

bolting. J Mine Vent Soc

S Africa 52(2):48-52

Thimons ED, Taylor CD,

Zimmer JA [1999]. Evaluating

the ventilation of a 40-foot twopass extended cut. Pittsburgh,

PA: U.S. Department of Health

and Human Services, Public

Health Service, Centers for

Disease Control and Prevention,

National Institute for

Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 99-138, RI 9648.

PURPOSE: Develop better ventilation techniques for

delivering air to the mining face and improved methane

sampling strategies for estimating face concentrations during

extended-cut mining.

RESEARCH SUMMARY: Normal distances between the end of the

ventilation curtain or tubing and the face often increase when extended-cut

mining methods are used. Increased setback distances can result in

reduced face airflow and increased methane concentrations. When

methane levels increase, there is a greater risk of frictional ignitions and

worker injury.

Improved techniques are being developed to maintain sufficient face

airflow and prevent methane ignitions during extended-cut mining. Testing

is conducted in a full-scale gallery where ventilation conditions for

extended-cut mining are simulated.

Using either a machine-mounted scrubber or water sprays helps to

reduce face methane levels during extended-cut mining. Tests show that

modifying the spray system by directing individual sprays toward the return

side of the entry further reduces face methane levels. Continuing research

is evaluating how the direction of the scrubber exhaust affects the airflow

patterns created by the scrubber and water sprays.

During underground mining, prevention of frictional ignitions can be

ensured only if there is accurate monitoring of methane concentrations,

particularly at the face where higher accumulations of the gas are most

likely to occur. Methane monitoring at the face is more difficult during

extended-cut mining because workers making the measurements must

remain under supported roof. Regulations require continuous methane

monitoring using a monitor permanently mounted on the mining machine and

usually located 5 to 10 feet from the face. In the test gallery, methane

levels are monitored concurrently at the face and at multiple locations on

the mining machine. Recommendations are provided for selecting the best

sampling locations on the mining and roof bolting machines for a range of

operating conditions.

It is not possible to check the accuracy of a machine-mounted

methanometer whenever it is under unsupported roof. In general, the

longer the extended cut, the less frequently instrument performance can be

checked. Techniques for evaluating instrument performance, using

response time as a criterion, are being evaluated and will be used to provide

a test protocol. Guidelines for determining methanometer reliability, based

on response time measurements, will be written.
Spokane and Pittsburgh Research Laboratories

58 Office for Mine Safety and Health Research

Collecting SCSRs for a long-term field evaluation study.

LIFE SUPPORT FOR SURVIVAL AND

RESCUE

RESEARCHER: John G. Kovac

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Self-contained

self-rescuer, respiratory

protection, mine emergency

escape

BIBLIOGRAPHY

Kyriazi N, Shubilla JP [1999]. 

Self-contained self-rescuer field

evaluation: sixth-phase results. 

Pittsburgh, PA: U.S.

Department of Health and

human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute for

Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 2000-128, IC 9451.

PURPOSE: Ensure that deployed self-contained selfrescuers (SCSRs) that pass their inspection criteria function

properly.

RESEARCH SUMMARY: On June 21, 1981, coal mine

operators in the United States were required to make

available to each underground coal miner an SCSR as an aid to escape in

the event of a mine emergency. Federal regulations require that each

person in an underground coal mine wear, carry, or have immediate access

to a device that provides respiratory protection with an oxygen source for at

least 1 hour, as rated by the certifying agencies: NIOSH and the Mine

Safety and Health Administration (MSHA).

NIOSH is conducting a long-term evaluation of SCSRs deployed in

underground coal mines. Mine operators are located that are willing to

participate in the study, deployed SCSRs are exchanged for new ones, and

then the deployed SCSRs are tested. The objective of this long-term

program is to evaluate the in-mine, operational durability of deployed

SCSRs. Of utmost concern is the successful performance of any SCSR

that passes its manu-facturer’s approved periodic inspection criteria. Only

apparatus that pass their inspection criteria are included in the study. Such

apparatus are relied upon to function successfully in an emergency. 

Apparatus that fail inspection criteria are expected to be removed from

service.

Seventeen mines were visited in MSHA Districts 2, 3, 4, 5, 6, 7 and 8 in

the most recent phase of this program. One hundred SCSRs were collected

for testing both on human subjects and on a breathing and metabolic

simulator. Past findings have resulted in modifications to quality assurance

procedures and inspection criteria, apparatus design changes, and recall and

decertification of SCSRs. In the most recent phase, it was found that

accelerated aging caused the breathing hose in an apparatus to deteriorate

and fail. This resulted in an industry-wide recall and inspection of nearly

40,000 apparatus. Another apparatus was discovered to have leaked

chemical from the canister into the breathing circuit, which was

undetectable by visual inspection criteria. To detect this internal damage,

an additional inspection criterion (a noise test) was added. This resulted in

an industry-wide field inspection of nearly 2,500 apparatus and replacement

of damaged units.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 59

One of three brattice cloth ventilation stoppings installed

in the Lake Lynn mine for this project.

VENTILATION OF LARGE-OPENING MINES

RESEARCHER: William D. Mayercheck

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-6683

KEYWORDS: Mine

ventilation, metal/nonmetal

mines, large openings,

anemometry, ultrasonic, laser

distance measuring

BIBLIOGRAPHY

Hartman HL [1997]. Mine

ventilation and air conditioning. 

3rd ed. New York, NY: John

Wiley & Sons, Inc.

Kohler JL, Thimons ED [1987]. 

An analysis of air volumeflowrate determinations for

mines. Min Sci Technol

6(1):17-29.

Thimons ED, Brechtel CE,

Adam ME, Agapito JFT [1986]. 

Performance characteristics of

large-capacity face ventilation

systems for oil shale mining. 

Pittsburgh, PA: U.S.

Department of the Interior,

Bureau of Mines, RI 9006.

PURPOSE: Extend the body of knowledge on airflow

within large underground mine workings.

RESEARCH SUMMARY: Hundreds of metal/nonmetal

underground mines operate throughout the United States. 

These operations extract commercial products from deposits, such as

limestone, salt, and gypsum. The mining process generates a wide variety

of gases and dusts, such as silica, diesel exhaust, radon, blasting byproducts,

and perhaps even methane. If these substances are airborne, they can

adversely affect the health and safety of individuals working underground. 

Many metal/nonmetal mines have large cross-sectional airways. The

largest airways feature areas that are over 60 times larger than an average

underground coal mine entry. These airways require adequate volumes of

fresh air to dilute, make harmless, and exhaust the toxic and, at times,

explosive byproducts.

For mines with enlarged airways, it is a challenge to provide an

adequate quantity of fresh air. Often this air must travel a considerable

distance to reach the working area. The quantity of air entering a typical

enlarged airway is such that the resulting air velocity is quite low. Low air

velocity can make large entries prone to air stagnation and recirculation. In

some entries, the air flow may be in opposite directions at different

elevations. The adverse health and safety impacts of inadequate fresh air

delivery in these mines can be serious. Mine operators, Mine Safety and

Health Administration inspectors, and Pennsylvania Bureau of Deep Mine

Safety officials have expressed concerns about the problem.

This project, which began in FY2000, is testing methods to measure

very low air flows in large-opening mines. First, a way to quantify air

volumes in large entries must be determined. The research is presently

determining how to divide the entry area to provide the most accurate

estimate of actual entry air volume. Here the use of conventional air flow

measurement techniques can be suspect. Traditional tools for measuring air

movement are vane anemometers, smoke tubes, tracer gas, and differential

pressures. The application or adaptation of other technologies, e.g.,

ultrasonic anemometry, is being ex-amined. An important goal of this

research is to publish a handbook of recommended practices for measuring

low air velocities, monitoring low air flows, and ultimately improving the

ventilation patterns in large-opening mines.
Spokane and Pittsburgh Research Laboratories

60 Office for Mine Safety and Health Research

In a December 1999 accident, a baseball-sized piece of flyrock went through the window of this truck and killed

the miner inside.

INVESTIGATION OF FLYROCK INJURIES

AND FATALITIES

RESEARCHER: Timothy R. Rehak

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Blasting,

explosives, flyrock, mining

BIBLIOGRAPHY

Fletcher LR, D’Andrea DV

[1986]. Control of flyrock in

blasting. In: Proceedings of the

12th Conference on Explosives

and Blasting Technique

(Atlanta, GA, February 9-14,

1986).

PURPOSE: Reduce fatalities and injuries caused by

flyrock and lack of blast area security in surface mining

operations involving coal, metal, and nonmetal mining.

RESEARCH SUMMARY: Annually, billions of pounds

of explosives are used in the United States by the mining

and construction industry. In all blasting operations, it is expected that

broken rock will move within the “blast area” identified by the blaster. It is

standard procedure for the blaster to ensure that no one is in the blast area

during a blast and that no rock leaves the blast area. When a person is

struck by rock within the blast area, it is called a blast area security

accident; when a person is struck outside the blast area, it is called a

flyrock, or “wild” flyrock, accident. Each year these accidents result in

fatalities and serious injuries. In some cases, the victims are persons who

are not connected with the mine.

Flyrock and lack of blast area security are the major causes of blasting

injuries and fatalities in surface mining. During 1978-98, flyrock and lack of

blast area security contributed to 74% of all fatal and nonfatal injuries

involving the use of explosives in surface coal mining operations. Data also

indicate that during the same period, flyrock and lack of blast area security

contributed to 65% of all fatal and nonfatal injuries involving the use of

explosives in surface metal and nonmetal mining operations.

A report reviewing accident reports from the Mine Safety and Health

Administration (MSHA) and other Government agencies has been

completed. Selected blasting sites are being visited, and procedures are

being examined to gain an in-depth understanding of the factors contributing

to blasting incidents. Statistical analysis of parameters and causative

factors of wild flyrock and blast area security accidents is being done. 

Through education, training, and improved procedures during blasting

operations, a reduction in the frequency of injuries from flyrock in blasting

operations is anticipated.

Partners/collaborators in the project are MSHA, the Institute of Makers

of Explosives, and the United Mine Workers of America.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 61

Experimental mine at Lake Lynn Laboratory.

LAKE LYNN LABORATORY

RESEARCHER: Eric S. Weiss

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-5010

KEYWORDS: Lake Lynn

Laboratory, health and safety,

explosions, fires, explosives

BIBLIOGRAPHY

Mattes RH, Bacho A,

Wade LV [1983]. Lake Lynn

Laboratory: construction,

physical description, and

capability. Pittsburgh, PA: U.S.

Department of the Interior,

Bureau of Mines, IC 8911.

Triebsch G, Sapko MJ [1990]. 

Lake Lynn Laboratory: a stateof-the-art mining research

laboratory. In: Proceedings of

the International Symposium on

Unique Underground Structures. 

Golden, CO: Colorado School of

Mines, Vol. 2, pp. 75-1 to 75-21.

PURPOSE: Provide a modern, full-scale realistic

laboratory for underground and surface research that

significantly contributes to the enhancement of workplace

safety and health for miners and other workers.

RESEARCH SUMMARY: Lake Lynn Laboratory near Fairchance, PA,

provides an isolated surface facility and a full-scale underground mine to

conduct large-scale research in mine disaster prevention and response, as

well as numerous other research areas of national interest requiring the

study of large-scale surface and underground safety and health problems. 

The ability of Lake Lynn to simulate virtually any underground coal mine

geometry provides a practical, realistic research laboratory for mining

research under various controlled conditions of ventilation, humidity,

pressure, and temperature. To facilitate the underground research,

electrical power, compressed air, water, communications, video lines,

natural gas lines, and a unique high-speed data-gathering instrumentation

system with a state-of-the-art computer system have been incorporated into

the design at the site. The surface facilities provide an isolated environment

in which large-scale research and testing can be conducted in a realistic, yet

environmentally controlled manner.

Ongoing research at Lake Lynn includes the development and

evaluation of fire suppression systems and early-warning technologies,

development and evaluation of mine seals and other ventilation structures,

evaluation of prototype mining equipment and sensors, noise control studies,

ventilation studies, roof support technologies, evaluation of explosive

incendivity and toxic gases, determination of explosion limits for combustible

dusts and ignitability of mists and vapors, mine rescue team training

evaluations in smoke-filled entries, and respirable dust deposition and diesel

particulate studies. The information generated as a result of the research at

Lake Lynn is vital to the members of the mining industry in the development

of improved technology and practices to protect mining personnel from the

many hazards associated with their jobs. Although the primary mission of

Lake Lynn is in support of mine safety and health programs, the unique

characteristics of the facility make it attractive for research in support of

other industrial problems. Cooperative research within these areas is often

conducted on a resource availability, cost-reimbursement basis. This

project supports and coordinates all of the Lake Lynn research efforts;

enhances the research capabilities of Lake Lynn; and maintains safety,

health, and environmental controls at Lake Lynn.
Spokane and Pittsburgh Research Laboratories

62 Office for Mine Safety and Health Research

Toxic fumes from blasts and explosions are one of the

many hazards faced by miners.

SURVEILLANCE

HAZARD SURVEILLANCE IN THE MINING

INDUSTRY

RESEARCHER: Gail L. McConnell, V.M.D.

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-6617

KEYWORDS: Hazard

surveillance, mining

BIBLIOGRAPHY

NIOSH [1996]. Results from

the National Occupational

Health Survey of Mining

(NOHSM). Cincinnati, OH:

U.S. Department of Health and

Human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute of

Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 96-136.

NIOSH [2000]. Injuries,

illnesses, and hazardous

exposures in the mining industry,

1986-1995: a surveillance

report. Pittsburgh, PA: U.S.

Department of Health and

Human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute of

Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 2000-117.

PURPOSE: Develop and implement a targeted hazard

survey for the mining industry.

RESEARCH SUMMARY: NIOSH plans to conduct, on

a periodic or ongoing basis, a nationally representative

survey(s) to evaluate the prevalence and distribution of

potentially hazardous working conditions among the U.S.

workforce. The surveillance of occupational hazards (e.g., chemical,

biological, physical, and psychosocial) will provide a rational basis for

guiding public health policy and research. Hazard surveys targeted by

industry, occupation, or hazard are also planned in addition to a

comprehensive, national hazard survey. Focused supplemental surveys

provide the opportunities to explore and confirm trends detected by the

national survey, as well as investigate newly hazardous conditions that result

from emerging technology. Mining has been selected as one of the initial

industries to be studied. It has the highest worker fatality rate of all

industries nationally, as well as in 26 States. A priori identification of

potential hazards permit safety and health threats to be successfully

mitigated before harm is done.

This is a new project developed in FY2000. An ad hoc advisory

committee composed of NIOSH researchers involved in mining safety and

health has developed a methodology to nominate and rank candidate hazard

conditions as to their relevance, feasibility, and value to mine safety and

health research. A working list of hazard survey candidates has been

selected. The next step is to develop survey methodology and protocols in

partnership with the national hazard survey team and other NIOSH divisions

for the first survey.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 63

Integration of GPS and GIS to map the distribution of airborne and ground dust and particulate matter.

IMPROVING SURVEILLANCE DATA

UTILIZATION THROUGH GEOGRAPHICAL

INFORMATION SYSTEMS

RESEARCHER: Nathan T. Lowe

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Surveillance,

GIS, GPS

PURPOSE: Develop and demonstrate geographical

information system (GIS) methodologies for spatially

mapping and analyzing accident and occupational disease

information.

RESEARCH SUMMARY: Combinations of mapping and analytical

techniques offer great potential for discovering regional differences in the

occurrence of accidents and health risks. Geographical information system

(GIS) and global positioning system (GPS) technologies will allow

surveillance data to be examined in relation to the geographic locations of

accidents or exposure sites. This information will enhance surveillance

efforts by allowing spatial analyses that are likely to reveal causal

relationships between injury variables not heretofore seen. A second goal is

to demonstrate and use GIS technology to disseminate mining industry

disease and injury data through computer networks such as CDC’s Intranet.

The first step was to produce basic GIS maps that show locations

associated with selected mining health and injury information by topic

(accident classification by State or commodity, for example). The project is

now exploring the usefulness of producing and publishing interactive maps

on the Intranet. A site is being developed and will be evaluated. Such

maps will allow NIOSH users to perform specialized queries by selecting

different combinations of themes from available options. Other GIS

products, such as Intranet facility management modeling, will be

investigated. Of special interest is a model that depicts the spatial

distribution of local accident sites, hazardous work areas, and/or chemical

storage, for example, with respect to safety equipment, exits, and office

space. Eventually, we hope to study the technology and feasibility of linking

GIS and document management technologies that would allow users to

access health and safety data simply by clicking on specific features of a

map showing the U.S. mining industry.

Knowledge gained in this research in GIS and GPS has allowed the

tools to be used to assist other research projects in gathering and analyzing

data. One such example is a “proximity warning system” that has the

potential of reducing haulage truck accidents. 
Spokane and Pittsburgh Research Laboratories

64 Office for Mine Safety and Health Research

Miner at a longwall face in an underground coal mine.

RISK FACTORS FOR ATHEROSCLEROSIS

AMONG COAL MINERS

RESEARCHER: Deborah D. Landen, M.D.

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-6617

KEYWORDS: Cardiovascular

disease, stress, coal mine dust

BIBLIOGRAPHY

Bosma H, Peter R, Siegrist J,

Marmot M [1998]. Two

alternative job stress models and

the risk of coronary heart

disease. Am J Pub Health

88(1):68-74.

Schnall PL, Belkic K,

Landsbergis P, Baker D, eds.

[2000]. The workplace and

cardiovascular disease. Occup

Med: State of the Art Rev

15(1). Philadelphia, PA:

Hanley and Belfus.

Yusuf HR, Giles WH, Croft JB,

Anda RF, Casper ML [1998]. 

Impact of multiple risk factor

profiles on determining

cardiovascular disease risk. 

Prev Med 27(1):1-9.

PURPOSE: Determine the prevalence of preclinical

atherosclerosis and risk factors for atherosclerosis among a

sample of coal miners.

RESEARCH SUMMARY: Based on death certificate data from

NIOSH’s National Occupational Mortality Database, coal miners seem to

have an elevated risk of death from heart attacks (myocardial infarction). 

Factors involved in the risk of atherosclerotic heart disease include genetics

and lifestyle issues, such as diet and smoking. Heart disease has also been

shown to be related to work in certain types of jobs, particularly jobs

involving high demands with low levels of control over work. The

relationship between workplace organizational factors and cardiovascular

disease is being investigated under the National Occupational Research

Agenda (NORA).

Recent developments in cardiovascular research allow for the detection

of preclinical atherosclerotic disease with a noninvasive technique involving

ultrasound measurement of the intimal lining of the carotid arteries. This

study is determining the prevalence of subclinical atherosclerotic disease, as

assessed by b-mode ultrasound of the carotid arteries, among a sample of

coal miners. Measurements of established risk factors for coronary heart

disease are to be obtained in this population, as well as measurements of

possible risk factors related to the work environment, including work-related

stress and inhalation of coal dust. The effect of these risk factors on

atherosclerosis is to be examined. This project is being conducted in

cooperation with the United Mine Workers of America.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 65

Sand and gravel mines are being studies to evaluate the

ecoomic and social consequences of an injury to a miner.

HAZARD REDUCTION IN SURFACE MINING

OF SAND AND GRAVEL

RESEARCHERS: C. M. K. Boldt and T. W. Camm

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

(509) 354-8000

KEYWORDS: Mining, sand

and gravel, economics

BIBLIOGRAPHY

Camm T [2000]. Economics of

safety at surface mine spoil

piles. Spokane, WA: U.S.

Department of Health and

Human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute for

Occupational Safety and Health,

DHHS (NIOSH) Publication

No. 2000-129, RI 9653.

PURPOSE: Provide data on the economic and social

costs of workplace injuries and fatalities at sand and gravel

operations based on the use of actual accident cases.

RESEARCH SUMMARY: The true costs of a mining injury or fatality 

involve more than just the direct costs to the mining company or its insurer,

but presently there is little or no good information on such costs. Direct

costs may include such things as medical and insurance administration

costs. Indirect costs include lost earnings, lost home production, lost fringe

benefits, employer costs of retraining and restaffing, coworker costs of lost

productivity, and time delays. Indirect costs can often exceed direct costs.

This task will involve collecting available information on direct costs

with the assistance of various collaborators. In addition, a protocol will be

developed to measure indirect costs associated with a worker injury or

fatality. This protocol will include a literature search, enhancement of the

existing system of obtaining direct and indirect costs, and collection of

associated social and economic impacts through personal and professional

interviews. This task will be completed during the first year of the project

when a pilot study will be done of a benchmark group. The benchmark

group is envisioned to be a small sand and gravel operation with six or

fewer workers that has not necessarily experienced an accident. This

group will be used to establish the methodology and test the economic

model. The benchmark model will determine direct and indirect cost

sources of data relevant to a serious accident.
Spokane and Pittsburgh Research Laboratories

66 Office for Mine Safety and Health Research

Dust emissions at a surface drilling site.

A HEALTH HAZARDS STUDY OF SURFACE

DRILLING OPERATIONS

RESEARCHER: R. J. Matetic

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-6648

KEYWORDS: Noise, silica,

control technology, mining,

drilling, construction

BIBLIOGRAPHY

Bartholomae RC, Parker RP

[1983]. Mining machinery noise

control guidelines. Pittsburgh,

PA: U.S. Department of the

Interior, Bureau of Mines,

Handbook 2-83.

Maksimovic SD, Page SJ

[1986]. Quartz dust sources

during overburden drilling at

surface coal mines. In: Wheeler

RW, ed. Proceedings of the

International Conference on the

Health of Miners. Cincinnati,

OH: American Conference of

Governmental Industrial

Hygienists, Vol. 14, pp. 361-66.

Page JS, Bailey P, Janot A

[1988]. New technology

controls dust on surface coal

mine drills. Eng Min Dec:30-31.

PURPOSE: Develop databases on silica and noise

exposures for surface drilling operations. Provide the basis

for hierarchical recommendations on engineering controls,

work practices, use of personal protection, and training

exercises for workers engaged in surface drilling operations.

RESEARCH SUMMARY: Long-term exposure to excessive levels of

respirable silica dust can lead to silicosis, a debilitating and potentially fatal

lung disease. Excessive levels of noise can result in noise-induced hearing

loss (NIHL), which is permanent and irreversible. Mine Safety and Health

Administration data from dust sampling conducted on drillers at surface

mines have shown that over 75% of silica samples exceeded the permissible

exposure level. A recent medical screening survey of surface mine

workers in Pennsylvania showed that about 13% of the workers with

drilling experience were diagnosed with silicosis. In addition, NIOSH data

indicate that at least 70% of mine workers (also engaged in drilling

activities) suffer NIHL severe enough to be classified as a hearing

disability. Similar equipment and working conditions exist at surface drilling

sites (water well, construction) that suggest that operators at these locations

may also be overexposed.

In this new project, noise and dust assessments on various types of

surface drills (air-rotary, tabletop rotary (motor), cable tool, auger, impact)

are being done in Minnesota, Pennsylvania, Wisconsin, and Ohio. Airborne

respirable dust (ARD) sampling, along with noise dosimetry, time-motion

analysis, and characterization of noise profiles, are being done at all drilling

sites. ARD sampling is being conducted to examine the effectiveness of

dust control practices and to assess dust exposures to the workers. Noise

dosimetry, time motion studies, sound pressure profiles, and narrow-band

sound level data are being collected to characterize (1) worker noise

exposure related to location and job activity, (2) the noise environment

surrounding different types of drilling rigs, and (3) prevailing frequencies

associated with dominant noise sources for assistance in determining

appropriate engineering controls. Training exercises are to be presented at

workshops nationwide that target operators, workers, and equipment

manufacturers.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 67

Haul trucks are expected to increase in size, and trolley

power is one possibility to improve efficiency. Such innovations can impact the safety and health of mine workers.

(Photo courtesy of Siemens AG.)

EMERGING TECHNOLOGIES

EMERGING TECHNOLOGIES AND OTHER

ISSUES IN MINING

RESEARCHER: George R. Bockosh

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-6602

KEYWORDS: Emerging

mining technology

BIBLIOGRAPHY

Fotta B, Bockosh GR [2000]. 

The aging workforce: an

emerging issue in the mining

industry. In: Proceedings of the

31st Annual Institute on Mining

Health, Safety and Research

(Roanoke, VA, August 27-30,

2000).

RAND Corp. [1998]. New

forces at work: industry views

critical technologies. Santa

Monica, CA: RAND Corp.

PURPOSE: Identify anticipated major changes that are

expected to impact the safety and health of mine workers

in the next 5-10 years.

RESEARCH SUMMARY: The mining industry is dynamic. It has made

significant gains in safety, health, productivity, production, and

environmental impact. In achieving these accomplishments, it has adopted

new technologies, accommodated encroachment of a world market, and

addressed new environmental regulations. All of these changes can

influence the safety and health of all mine workers. It is important to

anticipate future trends in technology, public policy, and demographics to

enable the NIOSH research program to take advantage of changes that

could improve miner’s safety and health and prepare interventions to

neutralize emerging threats.

This project is identifying major changes that are anticipated to impact,

for better or worse, the safety and health of mine workers in the next

5-10 years. The study is combining an analysis of expected commodity

production in the United States, anticipated social and public policy, and

emerging technologies to produce a series of recommendations for

research.

The demand for a commodity can influence miner safety and health. 

Trend analysis in coal production and employment has been completed, and

analyses for the other mined commodities are currently underway. A study

by RAND Corp. to identify critical technologies in the mining industry has

been completed. Public policy that impacts when and how mining is done is

also being reviewed.

The combined results of the analysis described above will result in the

identification of likely, new technologies and trends that are expected to

impact miner safety and health, along with recommendations for targeted

etiological and intervention research efforts.
Spokane and Pittsburgh Research Laboratories

68 Office for Mine Safety and Health Research

The safety framework and associated

guidance documents.

SYSTEM SAFETY: PROCESSOR CONTROL

APPLICATIONS 

RESEARCHER: Thomas J. Fisher

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

(412) 386-6648

KEYWORDS: Emerging

technology, control technology,

mining

BIBLIOGRAPHY

NIOSH [1999]. Technology

news 477: a systems safety

approach for programmable

electronics. Pittsburgh, PA:

U.S. Department of Health and

Human Services, Public Health

Service, Centers for Disease

Control and Prevention,

National Institute for

Occupational Safety and Health.

Sammarco JJ, Kohler JL, Novak

T, Morley LA [1997]. Safety

issues and the use of softwarecontrolled equipment in the

mining industry. In:

Proceedings of the IEEE

Industrial Applications Society

32nd Annual Meeting (New

Orleans, LA, October 5-9,

1997).

PURPOSE: Develop a series of recommendations

detailing safety processes for programmable electronicbased mining systems.

RESEARCH SUMMARY: Mining does not have a

formalized process for addressing programmable electronics

safety as do other industries. This project documents such a

process that encompasses hardware, software, humans, and

 the operating environment for functional safety of equipment

 with programmable electronics over the equipment's entire

life cycle. A risk-based, systems safety process, along with lessons learned

by other industries, is used. The project's recommended safety process will

benefit the U.S. mining industry and the global mining community since no

such system safety process specific to this technology in mining formally

exists.

Researchers reviewed various world standards addressing system

safety in different industries and used this information to draft

recommendation documents addressing the functional safety of processorcontrolled mining equipment applicable to the full life cycle of the

equipment. The Mine Safety and Health Administration (MSHA) is

currently cooperating in this project to achieve voluntary adoption of the

system safety recommendations by the mining industry. MSHA does not

intend to pursue a regulatory approach to system safety. A work group has

been formed that is composed of representatives from MSHA, NIOSH, and

the mining industry to develop a best practices guide to help implement the

system safety recommendations.

Key members of industry realize the need to address processor control

safety as shown by their continued participation in an Industry Safety

Workgroup. To investigate hazards and concerns identified by the panel,

NIOSH established extramural activity with The Pennsylvania State

University and the University of Alabama. Their studies substantiated the

claims of the panel. The same safety concerns have been voiced in

Australia during our meetings with Standards Australia and its Approval and

Certification group.

The outcome of this project is a set of safety framework documents

specifically tailored for mining applications (best practices and guidance) for

the emerging technology of programmable electronics and its associated

software. It also will furnish functional safety processes for design, testing,

approval/certification, operation, and maintenance of mining systems using

programmable electronics. The “Introduction” and “System Safety” documents have been completed; a draft of the “Software Safety” document is 

being reviewed by MSHA and the mining industry workshop.