U.S. Department of Health and Human Services

Public Health Service

Centers for Disease Control and Prevention

National Institute for Occupational Safety and Health CENTERS FOR DISEASE CONTROL

AND PREVENTION

A Compendium

of NIOSH Mining Research 

2000
National Institute for Occupational

Safety and Health

Spokane Research Laboratory

315 E. Montgomery Avenue

Spokane, WA 99207

National Institute for Occupational 

Safety and Health

Pittsburgh Research Laboratory

P.O. Box 18070

Pittsburgh, PA 15236-0070

Cover photos: (Left) NIOSH is investigating ways to reduce the respirable dust exposure

of mine workers at longwall mining operations. (Upper right) NIOSH is

studying technologies that will reduce haulage truck collisions at surface

mines. (Lower right) NIOSH has developed training tools for miners,

including a video on how to safely handle explosives underground.
A COMPENDIUM

OF NIOSH MINING RESEARCH

2000

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

February 2000
This document is in the public domain and may be freely copied or reprinted

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

ORDERING INFORMATION

Copies of National Institute for Occupational Safety and Health (NIOSH)

documents and information

about occupational safety and health are available from

NIOSH– Publications Dissemination

4676 Columbia Parkway

Cincinnati, OH 45266-1998

Fax:

Telephone:

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Web site:

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pubstaft@cdc.gov

www.cdc.gov/niosh

DHHS (NIOSH) Publication Number 2000-109
FOREWORD

To continue serving the safety and health needs of the Nation’s miners, NIOSH is coordinating

extensively with stakeholders across the country to obtain valuable insight into their priorities. 

This input, together with results from comprehensive analyses of safety and health data, has

allowed us to begin balancing the mining research program to address the prioritized needs of

miners in various industry sectors. 

This publication provides brief descriptions of the NIOSH projects dedicated to the primary

mission of reducing miners’ occupational injury and illness. The breadth and quality of research

represented here is a true testament to the dedicated NIOSH researchers working in this field. 

As problems and issues emerge, or are effectively addressed over time, the research program will

change accordingly, but it will continue to be based on a solid, scientific rationale and anchored

in reality.

NIOSH is always looking for better ways to communicate our research and results. This

publication is just one way we are reaching out to inform our mining partners and other

interested individuals and organizations about our current mining research projects. I look 

forward to continued interaction with NIOSH’s many mining partners.

Linda Rosenstock, M.D., M.P.H.

Director, 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

DUST MEASUREMENT AND CONTROL

Analytical Techniques for Silica ........................................................... 5

Personal Dust Monitoring ............................................................... 6

Tapered-Element Oscillating Microbalance (TEOM) Dust Monitors ................................. 7

Fundamental Scattering Properties of Respirable Dusts and Suspended Particulate Matter . . . . . . . . . . . . . . . . 8

Dust Control for Longwall Mining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Dust Control in Surface Coal Mining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Silica Dust Control for Underground Metal/Nonmetal Mines ...................................... 11

Silica Dust Control in Metal/Nonmetal Surface Mining .......................................... 12

Investigation of Silicate Dust Generation and Rare Earth Element Behavior in Coals . . . . . . . . . . . . . . . . . . . . . 13

Control of Silica Dust Exposures in Underground Coal Mining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Development of Enhanced Spray Dust Capture Principles for Improved Silica Dust Suppression . . . . . . . . . . . 15

DIESEL EMISSIONS AND TOXIC SUBSTANCES

Reducing Diesel Particulate Exposure in Western Mines ......................................... 16

Diesel Engine Emissions Measurement and Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Diesel Particulate Dosimeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Safety and Health Evaluation of a Fuel Cell-Powered Four-Ton Locomotive for Underground Mining . . . . . . . 19

Chemical Hazards in Mining and Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Exposure to Toxic Substances in Dust at Nonmetal Mines ....................................... 21

Toxic Fumes From Blasting .............................................................. 22

HAZARD DETECTION AND WARNING DEVICES

Hazard Reduction for Surface Mining Haulage Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Mobile Mining Equipment Warning Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Investigate Proximity Detection and Collision Avoidance ........................................ 25

Advanced Warning of Ground Stability Hazards ............................................... 26

Overhead Power Line Contact Alarm for Mobile Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Investigation of Electromagnetic Precursors to Rock Bursting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Smart Fire Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Ground Stability Assessment With Seismic Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Detection of Bridging in Surge Piles ........................................................ 31

INJURY PREVENTION AND EQUIPMENT DESIGN

Safety Enhancements for Rock Scaling Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Materials Handling Accident Reduction in Underground Mines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Engineering Controls for Reducing Jarring and Jolting in Surface Mines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Ergonomics Interventions in Mining ........................................................ 35

Injury Prevention for Metal/Nonmetal Drilling and Bolting Operations ............................... 36

Human Factors Design for Machine and Haulage Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Fundamental Studies in Electrical Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Mine Hoist and Elevator Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Design of Mine Ore Passes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
CONTENTS—Continued

Page

TRAINING AND EDUCATION

Interactive Training and Educational Development ............................................. 41

Evaluation of Interactive Mine Safety and Health Training Methods ................................. 42

Education for Effective Mine Emergency Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Accident Reconstruction and Training for Metal/Nonmetal Mines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Mine Rescue and Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Intervention Through Education and Training To Prevent Hearing Loss Among Miners . . . . . . . . . . . . . . . . . . 46

GROUND CONTROL

Safety Design for Underground Mine Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Reducing Ground Falls in Underground Stone and Nonmetal Mines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Identification and Control of Rock Burst Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Slope Stability Hazard Recognition for Metal/Nonmetal Mines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Reducing Injuries From the Failure of Coal Mine Roof Support Systems ............................. 51

Safe Monitoring of Engineered Backfill ...................................................... 52

Coal Bump Reduction Through Advanced Mine Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

FIRES, EXPLOSIONS, AND VENTILATION

Control and Suppression of Mine Fires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Improving CFR Safety Evaluations for Mine Ventilation Seals and Stoppings ......................... 55

Hydrostatic Evaluation of Mine Seals ....................................................... 56

Characterization and Mitigation of Mine Gas Emissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Explosives Hazard Surveillance and Evaluation for the Mine Safety and Health Administration . . . . . . . . . . . . . 58

Explosion Hazards Reduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Extended-Cut Air Delivery Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Life Support for Survival and Rescue ....................................................... 61

Laser Safety for Hazardous Locations ...................................................... 62

Ventilation of Large-Opening Mines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Investigation of Flyrock Injuries and Fatalities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Lake Lynn Laboratory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

SURVEILLANCE

Hazard Reduction in Surface Mining of Sand and Gravel ........................................ 67

Economic Cost Model for Traumatic Injuries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Improving Surveillance Data Utilization Through Geographical Information Systems . . . . . . . . . . . . . . . . . . . . 69

Risk Factors for Atherosclerosis Among Coal Miners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Analysis of Risk to Face Workers in Continuous Coal Mining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

EMERGING TECHNOLOGIES

Emerging Technologies and Other Issues in Mining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

System Safety: Processor Control Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Outcome Measures for Mining Safety and Health Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 1

A, Human subject testing of hardhat-mounted earmuffs;

B, Typical auditory assessment being conducted prior

to earplug testing.

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

1-800-35-NIOSH

KEYWORDS: Noise, hearing

loss, hearing protectors, earplugs,

earmuffs, acoustic monitors,

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 Occup Hearing

Conserv (CAOHC) 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 Occup Hearing

Conserv (CAOHC) Update 9(4).

NIOSH [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 level-dependent

hearing protectors and inexpensive personal acoustic monitors.

RESEARCH SUMMARY: The results of previous NIOSH research show that

miners develop hearing loss much more quickly than nonoccupationally noiseexposed individuals and that miners experience a greater severity of hearing loss than

would be expected for nonoccupational noise-exposed persons of the same age and

gender. Using hearing thresholds at 4,000 Hz as an indicator, coal miners experience

hearing loss 2.5 to 3 times greater than would be expected for persons not exposed to

occupational noise. At age 50, 90% of coal miners and 49% of metal/nonmetal miners

were found to have a hearing impairment. In comparison, only 9% of a

nonoccupationally exposed control group had a hearing impairment at age 50.

There are numerous barriers to the prevention of hearing loss among miners. 

In an effort to overcome some of these obstacles, this work was initiated to evaluate

practical technological advances in level-dependent hearing protectors and

inexpensive personal acoustic monitors. Experiments will involve analysis of this

new technology under both laboratory and field conditions. Laboratory

components will consist of controlled studies using an anthropometrically correct

test fixture as well as human subjects to evaluate the adequacy/effectiveness of

various hearing protective devices. Electroacoustical performance testing of new

noise monitors will also be conducted in a laboratory setting. Subsequent field

studies will determine the actual usefulness and practicality of the personal

protective/monitoring equipment as used in different mining situations.

It is anticipated that increased on-the-spot awareness of hazardous noise levels and

the availability of better-suited hearing protectors will provide a degree of protection

beyond what is currently attained in different mining environments. Therefore, the intent

of this project is to identify and adapt new acoustical technologies and products that have

a direct application to individual mine workers. With increased knowledge of these

technological advances, a greater demand for similar devices will likely occur, which, in

turn, will lead to a better understanding and awareness of hearing loss prevention

methods throughout the mining community. The ultimate goal is for widespread integration of useful hearing loss prevention products and devices into the daily routines of

miners.
Spokane and Pittsburgh Research Laboratories

2 Office for Mine Safety and Health Research

Noise measurements being made on a

continuous mining machine.

CROSS-SECTIONAL SURVEY: NOISE EXPOSURE

PATTERNS/SOURCES

RESEARCHERS: Eric R. Bauer and 

Roy C. Bartholomae

AFFILIATION: Pittsburgh Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

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.

Bartholomae RC, Parker RP

[1983]. Mining machinery noise

control guidelines. Pittsburgh, PA:

U.S. Department of the Interior,

Bureau of Mines, Handbook 2-83.

Bartholomae RC, Redmond GW

[1986]. Noise-induced hearing loss:

a review. In: Proceedings of the First

International Conference on Health

Safety of Miners. Cincinnati, OH:

Amer Conf Gov Ind Hyg 14:41-61.

Burks JA, Bartholomae RC [1998]. 

Investigation of intermittency in the

noise exposure pattern of longwall

coal miners. In: Proceedings of the

16th International Congress on

Acoustics and 135th Meeting of the

Acoustical Society of America, pp.

1523-1524.

PURPOSE: Establish representative noise exposure profiles of various

mining occupations and equipment.

RESEARCH SUMMARY: Noise-induced hearing loss has been

recognized as the most common occupational disease in the United States. 

Despite the progress achieved over the last 2 decades, overexposure to

noise in the mining workplace remains a serious problem for U.S. workers. 

Every day 80% of the Nation’s miners go to work in an environment where

time-weighted average (TWA) noise levels exceed 85 dBA. Even worse,

25% of the miners are exposed to a TWA noise level that exceeds 90 dBA. 

Research is needed to identify and characterize the noisiest equipment and

mine worker activities. This will ensure that the hearing of miners will be

preserved, that future hearing loss is prevented, and the quality of life of

our Nation’s miners will be enhanced.

The collection of baseline information will provide a current and systematic characterization of worker noise exposure patterns and mining

noise sources. This research is essential to the development of 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 will 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 TWA full-shift noise

exposures. In addition, a profile of the noise levels of the various mining

machines will be obtained using a handheld sound level meter.

To date, noise measurements have been made at Harrison Mining Co.,

NIOSH’s Safety Research Coal Mine at the Pittsburgh Research Laboratory

(underground coal); and Commercial Stone Co. (underground limestone). 

Cooperation is also expected from Consolidation Coal Co. The results of

these measurements will be used to design future noise exposure

measurements, in particular, which occupations need to be monitored and

which machines and which components and/or operating functions

contribute the most noise.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 3

Data collection in an underground coal mine.

A MODEL HEARING CONSERVATION

PROGRAM FOR COAL MINERS

RESEARCHER: David C. Byrne

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

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 to prevent hearing loss.

RESEARCH SUMMARY: Noise-induced hearing loss (NIHL) is a major

occupational health problem for coal miners. The prevalence of NIHL has

remained relatively unchanged for the last 20 years. A significant reason

for this is the lack of a systematic effective plan of intervention for the

mining community.

With researchers from The Pennsylvania State University, a cooperative agreement project was initiated 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, to implement this program

at a cooperating mine, to evaluate the program over a 5-year period, to

demonstrate its efficacy in preventing hearing loss, to transfer the findings

of this study to the coal mining industry (and others) as quickly and

thoroughly as possible, and to make the model HCP as “portable” as

practicable.

Other specific goals of the project are to fully 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.

The program design phase of the project is nearly complete. This included a significant amount of information collection regarding the current

state of hearing conservation measures at the cooperating mine, as well as

baseline hearing tests and noise measurements. The second main task is to

develop the detailed 5-year plan for each program element, including noise

exposure monitoring, engineering and administrative controls, audiometric

evaluations, use of hearing protection devices, education and motivation,

record-keeping, and program evaluation.
Spokane and Pittsburgh Research Laboratories

4 Office for Mine Safety and Health Research

The operation of mining equipment,

(e.g., the drilling of rock) can

contribute to high noise levels.

ENGINEERING CONTROLS FOR HEARING LOSS

PREVENTION

RESEARCHER: R. J. Matetic

AFFILIATION: Pittsburgh Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

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.

Burks JA, Bartholomae RC

[1994]. Evaluation of capmounted and over-the-head

earmuffs. In: Proceedings of

Inter-Noise (Toronto, Ontario,

Canada), pp. 303-306.

PURPOSE: Develop a strategy and implementation plan for utilization of

noise controls in mining to reduce noise-induced hearing loss (NIHL) among

mine workers.

RESEARCH SUMMARY: Overexposure to noise remains a widespread,

serious health hazard in the U.S. mining industries despite 25 years of regulation. Lower elements in the hierarchy of controls for reduction of noise

exposure, including administrative practices (e.g., job rotation), and use of

personal protective gear have been main sources of noise control, relying on

workers to properly wear and maintain their hearing protection. Analysis of

longitudinal data (audiograms) from miners in underground coal mines

suggests that this approach has not been effective and has resulted in a serious

NIHL problem among miners.

A balanced approach to the prevention of NIHL that includes not only

education, surveillance, and intervention, but also a research emphasis on low

cost or economically feasible engineering controls for noise is necessary. Engineering controls represent a permanent solution, whereas the use of personal

hearing protection is seen as an interim one. The new Mine Safety and Health

Administration rule for Health Standards for Occupational Noise Exposure is to

be effective on September 13, 2000. It requires the use of all feasible engineering

and administrative controls to reduce a miner’s noise exposure to the permissible

exposure limit. This project focuses on targeting engineering noise control for

mining as the first line of defense.

The approach is to review past mining research on noise control to determine what has been done and what remains relevant and to investigate best

practices of noise control currently available in the mining industry and in other

industries. A workshop will be held to bring together mine operators, union

officials, manufacturers of mining equipment, trade organizations, and

Government researchers and regulators to discuss and develop a strategy for

adopting economically viable engineering controls for noise control in mining. 

By bringing together all of the relevant parties in the workshop, strengths and

weaknesses of various implementation strategies can be refined. This strategy

is the basis of an implementation plan where appropriate engineering controls

are selected and targeted to reduce excessive exposure to noise on the job. The

quiet-by-design approach for noise control is being emphasized, but low-cost

retrofit of equipment with noise control measures is also a component.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 5

An eight-filter sample wheel speeds analysis by

automated sample handling and alignment.

DUST MEASUREMENT AND

CONTROL

ANALYTICAL TECHNIQUES FOR SILICA

RESEARCHER: Donald P. Tuchman

AFFILIATION: Pittsburgh Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Silica, dust,

exposure assessment, analytical

methods

PURPOSE: Develop technology to measure crystalline

silica in respirable coal mine dust samples by a rapid on-filter technique. 

RESEARCH SUMMARY: Respirable crystalline silica has long been

known as a toxic agent that causes silicosis and has also been found to

aggravate coal workers’ pneumoconiosis. The National Coal Workers

Autopsy Study records that 12% of miners have silicosis lesions. Other

studies show that more than 5% of surface mine workers have silicosis. 

Better ways to measure crystalline silica will enable the health and

enforcement community to pursue improved epidemiology, detail doseresponse relationships, verify effectiveness of control technology, and reduce exposure by enabling a rapid response to overexposure situations.

The analytical technique currently used to determine crystalline silica

content of coal mine respirable dusts is a lengthy and labor-intensive approach. It involves ashing filter samples and redepositing the ash onto

other filters. This research seeks to develop a new method in which filters

are placed directly in an infrared spectrometer, without pretreatment, and

silica content results are made available in a few minutes. This research

also seeks to automate the analyses. Automation will help reduce human

errors, minimize time and effort spent per sample, and maximize the benefits of the new method.

To date, customized software and hardware for the new type of analysis, including an automated eight-filter sample wheel, have been developed

and are almost fully debugged. Comparison analyses are in progress,

checking results with an established reference method, to evaluate the new

method’s accuracy. Extensive work is continuing to integrate advanced

features into the customized automation system. 

Besides the development of a new, rapid analytical method, the specialized software being developed is also a valuable product in its own right. 

A variation of the software, usable by a large number of laboratories, can

be employed without the need for any automation hardware at all. Its use

will reduce interlaboratory variations in the analysis of silica, thereby improving measurement accuracy for the analytical community as a whole.
Spokane and Pittsburgh Research Laboratories

6 Office for Mine Safety and Health Research

The dust dosimeter has two components: a small pump

and a dust detector tube.

PERSONAL DUST MONITORING

RESEARCHER: Steven J. Page

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining, dust,

monitoring

BIBLIOGRAPHY

Volkwein JC, Page SJ, Baron

PA, Deye GJ [1997]. Particulate penetration of porous

foam as a low flow rate respirable dust size classifier. In:

16th Annual Conference of the

American Association for

Aerosol Research (Denver, CO,

October 13-17, 1997).

Volkwein JC, Schoeneman AL,

Page SJ [1999]. Laboratory

evaluation of pressure

differential-based respirable

dust detector tube. In: Tien JC,

ed. Proceedings of the Eighth

U.S. Mine Ventilation Symposium. Rolla, MO: University

of Missouri-Rolla Press,

pp. 255-261.

PURPOSE: Investigate a disposable and inexpensive dust

exposure assessment device known as the dust dosimeter and

the fundamentals of the measurement technology used in its

design. In addition, this program will be responsible for the

certification of coal mine dust personal sampling units.

RESEARCH SUMMARY: Assessment of personal

respirable dust exposure is a critical step in eliminating

dust-related occupational illness and disease. Currently, dust levels are

measured by weighing dust collected on filters or with instantaneous

electronic dust monitors. The filter method is used for compliance

purposes, and results can take several weeks to process. The delay in

receiving filter results prevents timely correction of excessive dust levels. 

Electronic devices are complex, expensive, and cumbersome. The

approach is to develop an end-of-shift, inexpensive dust measuring device

that resembles a gas detector tube and measures the differential pressure

across a filter as a function of dust loading. It is intended to be used as a

screening tool to decide if additional, more rigorous, dust evaluation is

warranted. It will also quickly alert miners and mine operators when miners are overexposed to dust. The relationship between differential pressure

across various types of filter media and the mass of respirable dust collected on the filters, as well as the effect of diesel exhaust particulate on the

differential pressure, is being studied.

The development of the dosimeter has been done in partnership with

the United Mine Workers of America, the U.K.’s Health and Safety Executive, the Mine Safety and Health Administration, Consolidation Coal Co.,

Jim Walter Resources, Inc., The Pennsylvania State University, and the

University of Minnesota. A Cooperative Research and Development

Agreement (CRADA) partner has been added to the work for subsequent

commercialization of the dosimeter. Prototype versions of the dosimeter

have been received and tested, and manufacturing problems are currently

being resolved. A new sampling pump for the dosimeter has been

developed under the CRADA. This pump provides higher pressure

resolution, displays output directly in respirable dust concentration, and

provides midshift and end-of-shift readouts. The successful outcome of the

work will be a new tool and a new approach to dust monitoring in mining. 

This program has also absorbed the responsibility for certifying each

new coal mine dust personal sampling unit that will be used for personal

compliance sampling in all underground and surface mining operations.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 7

Person-wearable dust monitor.

TAPERED-ELEMENT OSCILLATING MICROBALANCE

(TEOM) DUST MONITORS

RESEARCHER: Fred N. Kissell

AFFILIATION: Pittsburgh Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Dust, exposure

assessment, coal mining, dust

sampling, black lung

BIBLIOGRAPHY

 

Volkwein JC, Kissell FN

[1999]. Update on the

development of personwearable dust monitors. In:

Proceedings of the 30th Annual

Institute on Mine Safety and

Health (Salt Lake City, UT,

August 9-11, 1999).

PURPOSE: Develop a person-wearable dust monitor using the taperedelement operating principle.

RESEARCH SUMMARY: Prolonged inhalation of respirable coal mine

dust can cause coal workers’ pneumoconiosis. Accurate measurement of

respirable dust is crucial to successfully reducing dust exposures and

eliminating disease. However, the sampling of coal mine dust has

remained virtually unchanged in the last 30 years since the Federal Coal

Mine Health and Safety Act of 1969 mandated a dust exposure limit of

2 mg/m3

. The need for a new type of coal mine dust sampling device is

evident. The Mine Safety and Health Administration (MSHA), the mining

industry (the Bituminous Coal Operators Association), and the United

Mine Workers of America have requested that NIOSH develop a personal

respirable dust monitor that can provide a rapid readout of a full-shift

exposure and real-time respirable dust concentration readings during a

shift.

To fill this need, NIOSH has awarded a contract to Rupprecht and

Patashnick Co., Inc. (R&P) in Albany, NY, to develop a person-wearable

dust monitor using the tapered-element operating principle. The operating

principle uses a replaceable filter cartridge mounted on the narrow end of a

hollow tapered tube. The wide end of the tube is fixed. Air passes through

the filter and down through the tube to a pump. The tapered tube with the

filter on the end is maintained in oscillation. The oscillation frequency

depends on the characteristics of the tube and the filter mass at its end. As

dust collects on the filter, the mass change is sensed as a frequency change

in the oscillation of the tube. The mass of dust collecting on the filter is

then determined directly. Since frequency can be measured accurately, the

method can measure very small mass changes. The required accuracy is

±25% of the current sampling method, and the size and weight are expected

to be reasonable for a miner to wear.

These units will be evaluated jointly by NIOSH and MSHA for

performance and reliability in underground mine tests. Upon acceptance of

the production prototypes, five more units will be constructed and delivered

to NIOSH.
Spokane and Pittsburgh Research Laboratories

8 Office for Mine Safety and Health Research

Light-scattering test apparatus schematic.

FUNDAMENTAL SCATTERING PROPERTIES OF RESPIRABLE DUSTS AND

SUSPENDED PARTICULATE MATTER

RESEARCHER: C. D. Litton

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Respirable

dust, diesel particulate matter,

combustion aerosols, light

scattering, pneumoconiosis,

silicosis

BIBLIOGRAPHY

Litton CD [1997]. Fractal

properties of smoke produced

from smoldering and flaming

fires. In: Proceedings of Symposium on Combustion, Fire

and Explosion, and Alternative

Fuels, ASME International

Mechanical Engineering Congress and Exposition (Dallas,

TX, November 16-21, 1997).

Litton CD, Chaiken RF [1996]. 

The role of radiation absorption

in defining explosibility of

coal/rock dust mixtures. In:

Proceedings of the 26th International Symposium on Combustion (Naples, Italy), pp. 1571-

1577.

PURPOSE: Explore the light-scattering properties of respirable mine

dusts and combustion-generated submicrometer particulate matter. Use the

results of these investigations to develop improved instrumentation for

measurement and characterization of respirable dusts and suspended

particulate matter.

RESEARCH SUMMARY: Pneumoconiosis and silicosis are two major

health hazards resulting from prolonged exposure to respirable coal dust

and silica dust, respectively. In addition, suspended particulate matter from

combustion sources, such as diesel engines or other combustion processes,

lie entirely within the respirable range, and prolonged exposure results in

adverse health effects. Devices for the measurement and characterization

of respirable mine dusts and suspended particulate matter are needed to

assess worker exposure to these health hazards and to evaluate control

technologies.

When airborne dusts or suspended particulates are irradiated with light,

the light is scattered in all directions. The intensity of light scattered at any

particular angle depends on the wavelength of the light and the size, volatility, and mass concentration of the dust or suspended particles. Both

theory and experiment indicate that at a scattering angle of around 20° to

30°, the size and volatility of respirable coal dusts have a negligible impact

on the measured intensity so that this intensity is directly proportional to

the mass concentration of the dust. At an angle of 15°, equal concentrations of either respirable coal dust or diesel particulate matter (DPM) yield

equal intensities of scattered light. At larger angles, the intensities from

DPM are significantly greater.

These results, while tentative, imply that devices that measure lightscattering signatures at one or more specific angles in the range of 15° to

30° offer significant promise for respirable dust or DPM measurement and,

possibly, for determination of mass fractions of dust/DPM mixtures. As

this basic research project progresses, these implications will be explored

in greater detail. We will also evaluate light-scattering signatures from

silica dust and other suspended particulate matter.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 9

Dust generation and water spray application at an

operating longwall face.

DUST CONTROL FOR LONGWALL MINING

RESEARCHER: Jay F. Colinet

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

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,

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 (Wisla, Poland, Oct.

5-7, 1999), chapter XI.

Organiscak JA, Colinet JF

[1999]. Influence of coal properties and dust control parameters

on longwall respirable dust levels. 

Min Eng 51(9):41-48.

Organiscak JA, Colinet JF,

Koziel A [1999]. Longwall operational parameters and dust

levels measured in Poland’s coal

mines. In: Proceedings of Longwall USA International Exhibition & Conference, pp. 171-184.

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 approximately 9% of the workers with 25 or more years of

mining experience were diagnosed with CWP. Longwall mining operations

now account for over 50% of underground coal production, and average

shift production levels on longwalls has increased over fourfold since 1980. 

As more coal is mined, greater quantities of respirable dust are generated

and the potential for worker overexposure increases. In response to

increased production levels, longwall operators have increased the level at

which ventilating air and spray water are applied in an effort to provide

greater dust control.

This multitasked research project is addressing improvements in

control technology for longwall mining operations. Laboratory testing is

being conducted at a full-scale test gallery at the NIOSH 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. 

These data will allow longwall operators to optimize dust controls for

conditions at their respective mines. Additional laboratory testing is being

conducted within a specially designed wind tunnel to evaluate the

entrainment of respirable dust in high-velocity airstreams, which will

represent dust liberated during the advance of shield supports. Mine site

testing will be used to evaluate the effectiveness of novel dust control

technologies after implementation by industry.
Spokane and Pittsburgh Research Laboratories

10 Office for Mine Safety and Health Research

Dust sampling array for assessment of respirable

dust concentrations.

DUST CONTROL IN SURFACE COAL MINING

RESEARCHER: Jeffrey M. Listak

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Surface mining,

respirable dust, drilling, silica, dust

control technology

BIBLIOGRAPHY

NIOSH [1997]. Silica...it’s not just

dust. 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. 97-118.

NIOSH [1998]. NIOSH hazard

controls: 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 [1996]. 

Assessment of airborne dust

generated from small truckmounted rock drills. Pittsburgh,

PA: U.S. Department of the Interior, Bureau of Mines, RI 9616.

PURPOSE: Identify the effectiveness of existing dust control

technologies used for rock drills and bulldozers at surface coal

mining operations and improve coal miners’ health protection

from silica dust exposure through the advancement of existing 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 are at particularly high risk because

of the potential of being exposed to extremely high levels of respirable silica

dust when drilling through rock containing silica. A study of job categories

was conducted to examine exposure data collected during a 2-year period at

surface mine sites, preparation plants, and shop/maintenance facilities. This

study concluded that occupations associated with highwall drilling (operator

and helper) had the highest silica exposures of all job categories examined.

Research efforts will focus on the interactions between drilling parameters, overburden lithology, and bit design and how these interactions affect

respirable silica dust generation. Once the drilling parameters, bit designs,

and rock characteristics have been defined in terms of their impact on silica

generation, appropriate control technologies can be developed to reduce

silica emissions. Furthermore, many surface drills have dust containment

and capture problems at the shrouded drill table above the hole. Laboratory

and mine site development work for improving the highwall drill’s primary

dust collection system is planned. Mine Safety and Health Administration

(MSHA) dust exposure data show that, in addition to drilling personnel,

bulldozer operators represent the next occupation at surface coal mines that

most frequently exceed the permissible exposure limit for respirable dust. 

Consequently, during surface mine surveys, dust sampling will also be

conducted to identify silica sources, exposures, and controls for bulldozer

operators. Additionally, investigations into improving quality control

methods to ensure the integrity of enclosed environmental cabs will be

done through cooperative work with mining companies, equipment manufacturers, and MSHA.

This research will improve dust control technology alternatives provided for surface coal mining operations. 
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 11

Drilling operations in the stone industry are a potentially

high source of silica dust liberation.

SILICA DUST CONTROL FOR UNDERGROUND METAL/NONMETAL MINES

RESEARCHERS: Gregory J. Chekan and

Roy H. Grau III

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Underground

mining, silica dust, dust control

technology

PURPOSE: Reduce silica exposure among workers in underground

metal/nonmetal mines. Assess the effectiveness of current dust control technologies

and develop or modify existing technologies where needed.

RESEARCH SUMMARY: The health hazards associated with overexposure to

respirable silica dust in the mining industry have been well documented. Chronic

overexposure to respirable silica (particle diameter < 10 microns) leads to progressive

lung deterioration known as silicosis. An analysis of the Mine Safety and Health

Administration (MSHA) compliance dust sampling data has shown that a high

percentage of samples from underground stone, metal, and nonmetal mines exceeded the

permissible exposure limit (PEL) for silica. From 1993 to 1997, on average between

20% and 25% of underground respirable dust samples from these three mining sectors

exceeded the PEL for respirable quartz. In the stone industry, most silica overexposures

have historically occurred in limestone mines. The occupations most at risk include

truck drivers, crusher operators, front-end loader operators, and rotary drill operators. In

the metal industry, gold mining has the most silica problems. Several occupations have

been identified as being chronically overexposed. In the case of scoop-tram operators,

almost 50% of the samples exceeded the PEL. Silica exposure needs to be addressed

through improved dust sampling methodologies and the development of practical dust

control technologies. 

Metal/nonmetal mining encompasses many types of commodities, each with

different mining types and methods. For instance, limestone generally uses room-andpillar mining methods. Gold operations may use long-hole open stoping or underhand

drift-and-fill methods. These mining methods present unique dust control problems for

the occupations specific to these operations.

In this new project, the evaluation of current technologies and the development of

new ones will focus on four primary areas: (1) dust control at the generating sources

such as that produced during drilling, blasting, or loading operations, (2) dust capture

after generation involving the application of ventilation and water sprays, (3) dust

control in contained working areas such as enclosed cabs on loading and haulage

equipment, and (4) dust avoidance by implementing control technology that directs dust

away from workers. This research will provide metal/nonmetal mine operators with

data identifying major sources of silica dust liberation and potential controls for

reducing worker exposure.
Spokane and Pittsburgh Research Laboratories

12 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

RESEARCHER: Andrew B. Cecala

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Silicosis, control

technology, surface mining,

mineral processing

BIBLIOGRAPHY

Cecala AB [1998]. Supplementing your dust control equipment

with whole-plant ventilation. 

Powder and Bulk Eng 12(1):

19-32.

Cecala AB, Timko RJ, Thimons

ED [1999]. Lowering respirable

dust exposures at mineral processing facilities. In: Tien JC, ed. 

Proceedings of the Eighth U.S.

Mine Ventilation Symposium. 

Rolla, MO: University of

Missouri-Rolla Press, pp. 221-

227.

PURPOSE: Develop control technology to reduce worker

exposure to silica and other harmful contaminants in metal and

nonmetal surface mining operations. 

RESEARCH SUMMARY: Although all types of respirable

dust are potentially harmful to a worker’s lungs, crystalline silica is

even more hazardous because it causes progressive deterioration to the lungs once it has

become embedded in the tissue. More than 1 million workers across the United States

are exposed to silica dust. Mine Safety and Health Administration (MSHA) records

show that since 1974, more than 82,000 of the 134,000 full-shift air samples collected by

inspectors in the metal/nonmetal mining industry contained at least 1% silica. In a

similar report, MSHA stated that the occupations with the greatest exposure to silica are

bag operators, bag stackers, and laborers. Maintenance, cleanup, and utility workers are

also often overexposed because their mobility makes it hard to provide them with

engineering controls.

In a cooperative effort between Malvern Minerals Co., MSHA, and NIOSH, a study

was recently completed to reduce a bag stacker’s exposure at a ground silica sand

packaging station using a semiautomated palletizing machine. A number of NIOSH

modifications made to the palletizing setup were successful in significantly lowering the

bag stacker’s respirable dust exposure. 

Work is continuing at mineral processing operations to determine the impact of

silica sand plant structural designs on ambient dust and noise levels within each

operation. Three structural designs–a masonry pebble mill and screening tower, an open

structure screening facility, and a metal-sided pebble mill–have been evaluated to date.

A cooperative effort is underway between NIOSH, Clean Air Filter Co., and U.S.

Silica to lower respirable silica dust exposures to surface mine drill operators by

improving filtration efficiency and pressurization in enclosed cabs on rotary percussive

drills. Baseline testing has been completed, and an improved filtration and

pressurization system has been installed. This research will lead to a cleaner work

environment for workers in the metal/nonmetal mining industry by reducing respirable

dust exposures, especially silica dust. This will decrease the potential for life-threatening

lung diseases.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 13

Field description of coal compositional banding in the

Lower Kittanning Coalbed prior to collecting a channel

sample at a surface coal mine.

INVESTIGATION OF SILICATE DUST GENERATION AND RARE EARTH ELEMENT

BEHAVIOR IN COALS 

RESEARCHER: Steven J. Schatzel

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining, mixed

exposures, silica, chemistry

PURPOSE: Explore the origins of the silicate mineral fraction in coal dust produced

during mining. Investigate the behavior of rare earth elements (REEs) in coal and

characterize their geological/biological interactions. 

RESEARCH SUMMARY: This new project will conduct basic research into two

elements, silica and rare earth elements (REEs), that can be liberated during the mining

of coal and can cause adverse health impacts to exposed workers. Miner exposure to

silica dust has been well documented, as have the debilitating effects of silicosis. The

toxicity of certain REE compounds has raised concerns about respiratory illnesses such

as pneumoconiosis and genetic aberrations. About 20 cases of REE pulmonary diseases

caused by the inhalation of metal dusts have been documented.

The relationship between the silicate mineral composition of whole coal samples

and the mineral composition of dusts produced by the mining of U.S. coalbeds is not

clearly understood. The concentrations of rare earth elements (REEs) produced in

occupational settings are not reported. The nature of REE exposures is very broad and

includes a wide variety of worker exposures. In 1996, a U.S. mine was the second

highest producing rare earths mine in the world. The goal of this project is to (1)

compare the silicate fraction of coal dust produced during mining to that of whole coal,

(2) investigate the fundamental behavior of REEs in nature, and (3) develop new inhouse analysis capabilities for determining the origins of potentially toxic materials. 

NIOSH is currently collaborating with the University of Pittsburgh on the REE

research task. A technical review of the draft REE work plan, the methodology for coal

and rock sample preparation, and sample analysis procedures were completed. A

sample collection protocol has been developed, and five mines have been visited to

collect coal and rock samples. The silicate composition of the host material will be

determined and then related to the silica content of the airborne dust levels associated

with mining the host material. Further definition of the relationship between silica and

REEs in host material and worker exposure during mining will allow for improved

controls to be developed to reduce worker exposures.
Spokane and Pittsburgh Research Laboratories

14 Office for Mine Safety and Health Research

Field assessments are measuring the roof bolter

operator’s exposure to respirable silica dust.

CONTROL OF SILICA DUST EXPOSURES IN

UNDERGROUND COAL MINING

RESEARCHER: Gerrit V. R. Goodman

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Silica exposures,

dust, coal mining, ventilation

BIBLIOGRAPHY

Goodman GVR, Listak JM

[1999]. Variation in dust levels

with continuous miner position. 

Min Eng 51(2):53-58.

Listak JM, Goodman GVR,

Jankowski RA [1999]. Considerations for estimating remote

operator dust exposure using

fixed-point samples on continuous mining sections. In: Tien

JC, ed. Proceedings of the

Eighth U.S. Mine Ventilation

Symposium. Rolla, MO: University of Missouri-Rolla Press,

pp. 249-254.

PURPOSE: Develop means of reducing exposures to respirable silica dust at the

continuous mining machine and roof bolter operators’ 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%,

the dust standard is reduced to 10/(% silica), which limits silica exposures to 100

μg/m3

. Recent sampling data show that roughly 40% of continuous mining machine

operator samples exceeded 5% silica, and 25% of these samples exceeded 100

μg/m3

. For the roof bolter operator, nearly 60% of these samples exceeded 5%

silica and one-third exceeded 100 μg/m3

.

Information identifying dust control and ventilation practices, geologic

characteristics, and occupational dust exposures was collected for 80 continuous

mining operations with silica levels above 5%. Forty of these operations

maintained silica concentrations less than or equal to 100 μg/m3

 in the majority of

their dust samples; the remaining 40 operations had difficulty in maintaining silica

below 100 μg/m3

. Comparing data from these two groups indicated that those

operations having difficulty controlling silica levels had the greatest overexposures for

roof bolter operators when the roof bolting machine was operating downwind of the

continuous mining machine.

Field assessments are underway to document roof bolter exposures, while

laboratory testing is planned to assess improved dust control technology for roof bolter

operators. Canopy air curtain technology offers the potential to reduce roof bolter

exposures to respirable coal dust and silica dust when working downwind of the mining

machine. This air curtain device mounts on the underside of the roof bolter operator’s

canopy and provides a flow of filtered air over the roof bolter operator. Lab testing will

be conducted to optimize performance of this control technology, followed by an inmine evaluation.

Water sprays and ventilation airflow are used for control of 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 fullscale test facility in conjunction with state-of-the-art gas monitoring equipment,

testing will be conducted to evaluate different water spray and ventilation airflow

designs for effectively controlling both respirable dust exposures and methane gas.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 15

Water spray application on an underground coal mining

machine.

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

1-800-35-NIOSH

KEYWORDS: Respirable

crystalline silica dust, mining,

spray dust capture

PURPOSE: Develop novel spray nozzle technologies

and 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. Coal mining

has the highest industrial silica-related deaths (9.5%); metal mining has the

third highest (8.6%). Coal mining machine operators were the most

frequent occupation (16.0%) recorded on silicosis-related death certificates

during 1991-92. MSHA’s compliance data indicate that a significant

portion of the airborne respirable dust samples collected in mines exceed

the mandated permissible exposure limits (PELs). Nearly 25% of the coal

mine dust samples and over 20% of the metal mine dust samples exceed the

MSHA-mandated PELs. About 13% of the dust samples from nonmetal

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

data indicate that there is a high likelihood of overexposure to silica dust in

the mining industry, especially in coal and metal mines. 

One approach to combat the amount of respirable silica dust exposure

present in the mining industry is to develop 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 contact by (1) increasing the number of smaller sized spray droplets per unit volume of water utilized and

(2) optimizing the energy transfer of spray droplets with the dust-laden air.

The first phase of this new project will involve laboratory investigation

and development of several novel spray nozzle technologies and fluid dynamic principles for improving water droplet and dust particle interaction. 

The second phase of this research will involve the integration and demonstration of these enhanced spray technologies as viable engineering controls

for improving respirable silica dust suppression from mining, crushing,

screening, and milling processes.
Spokane and Pittsburgh Research Laboratories

16 Office for Mine Safety and Health Research

Diesel fumes generated by mining machines.

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

1-800-35-NIOSH

KEYWORDS: Diesel exhaust,

diesel particulate matter, worker

exposure, mine health and

safety.

BIBLIOGRAPHY

Miller A [1999]. Clean fuels

and power for the 21st century. 

Presentation at the 19th Annual

Governor’s Health and Safety

Conference (Alaska, March 29,

1999).

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. MSHA has recognized 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 mine workplace through partnerships. 

This project will support the western mining partnerships through control

technology research applications on existing diesel equipment.

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

diesels are used in close quarters, i.e., factories and warehouses. The transfer of technology to these sectors could easily reduce exposure for hundreds of thousands of employees in nonmining industries.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 17

Diesel exhaust filtration on mining equipment offers substantial reductions in workplace concentrations of diesel

particulate matter. 

DIESEL ENGINE EMISSIONS MEASUREMENT AND ANALYSIS

RESEARCHER: George H. Schnakenberg, Jr.

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Underground

mining, diesel, exhaust, soot,

elemental carbon, measurement,

controls

BIBLIOGRAPHY

Cantrell BK, Watts WF Jr.

[1997]. Diesel exhaust aerosol:

review of occupational exposure. Appl Occup Environ 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 and

control 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 (soot) to be a suspected or

probable carcinogen. Recently one nongovernment body, responsible for

recommending occupational exposure guidelines, recommended a maximum

average level of 50 micrograms of diesel particulate matter (DPM) per cubic meter

of air. About 30,000 U.S. underground mine workers are exposed to DPM levels

that are up to 20 times this level. 

This project directly addresses the issue of accurate measurement of DPM

(which is mostly carbon) in the presence of mine dusts (such as coal, limestone, and

other ores), oil mists, and cigarette smoke, which also contain carbon. Both

analytical methods for filter samples and direct- indicating instrument methods are

being investigated. Laboratory and field experiments are being performed to define

and mitigate the effects of nondiesel dusts on the measurement of DPM. 

The rapid advances in diesel engine emission control technology, which are

driven by more stringent air quality standards for highway and off-highway trucks,

are being followed. This knowledge is being used to provide technical and scientific

support to a partnership among the Bituminous Coal Operators Association, the

United Mine Workers of America, and NIOSH. The objective of this partnership is

the application of technologically feasible controls to curtail worker exposure to

DPM. 

This project will reduce uncertainties in the measurement of workplace

concentrations of DPM. This will enable better measurement of worker exposures

and better assessment of the effects of control technology on tailpipe emissions and

workplace concentrations and thus better day-to-day control over engine emissions.

Control technologies, which have the potential of reducing emitted DPM by 80% to

95%, will be studied and feasible ones selected for demonstration. As a result,

mines will use cleaner engines, apply better maintenance, and use control systems

that will reduce worker exposures to DPM by factors of 10 to 20, thereby reducing

exposure levels to that of other occupations.
Spokane and Pittsburgh Research Laboratories

18 Office for Mine Safety and Health Research

Typical mine diesel and dust sizes form the basis of a

measurement technique to determine DPM in mining.

DIESEL PARTICULATE DOSIMETER

RESEARCHER: Jon C. Volkwein

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining, diesel

particulate matter, monitoring

PURPOSE: Investigate the correlation of differential

pressure increase with diesel particulate mass loading of

filters as a potential real-time method of monitoring work

environmental diesel particulate levels.

RESEARCH SUMMARY: Levels of diesel particulate matter (DPM) in

mining and other industrial settings represent an increasing health concern

because of the presence of carcinogens associated with the particulate. Dieselpowered mining equipment is the main power source in metal and nonmetal

mining and is being used more frequently in U.S. coal mines. Recent

legislative rulemaking by the Mine Safety and Health Administration has

increased the need to understand what fraction of the mine dust is attributable

to diesel exhaust. However, methods to monitor the levels of DPM in mining

have, until recently, been unavailable. Studies indicate that adverse health

impacts result from overexposures to DPM, and the American Conference of

Governmental Industrial Hygienists has proposed an exposure limit of 150

micrograms per cubic meter. DPM monitoring is near the top of the health and

safety priority list of the United Mine Workers of America. Current methods to

monitor DPM do not permit timely results that would enable immediate action

to be taken to prevent overexposures.

This project builds on the existing dust dosimeter project that monitors

exposure to coal mine dust based on differential pressure across a filter. 

During the course of that project, it was found that diesel particulate in mines

greatly increased the response of filter differential pressure to the mass

relationship of the dust dosimeter. The intent of this project is to take the filter

clogging disadvantages of DPM with the dust dosimeter and use the increased

response as a way to monitor DPM.

Development of technology to quickly assess mine DPM levels in nearreal-time would allow for immediate corrective action to occur if these concentrations are found to be excessive. This technology would be of use to all

mines operating diesel-powered equipment. Furthermore, such a tool would

enable workers and management alike to monitor DPM levels and increase

their personal awareness of the quality of their work environments. The

technology may also be of use to other industries, such as bus and rail

maintenance shops, as well as the environmental monitoring of submicrometer

particulate.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 19

Small (4-ton) mine locomotive (courtesy Goodman).

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

1-800-35-NIOSH

KEYWORDS: Mining, fuel

cell, diesel, particulate, noise,

locomotive

PURPOSE: Investigate the safe storage, distribution, and use of hydrogen as

a vehicle fuel; the air quality improvements anticipated when diesel technology

can be replaced by fuel cell technology; and the improvements expected in

workplace noise levels by implementing fuel cell technology in mining.

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

Propulsion Institute, fuel cell technology is anticipated to be demonstrated

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

Three areas were identified as particular safety and health concerns when

existing diesel or electric technology is compared to emerging fuel cell

technology: (1) the safe storage, distribution, and use of H2 as a fuel,

(2) air quality improvements, and (3) 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. The literature review produced general and specific information on H2 production, storage, and use

in existing environments, but only limited information on specific underground applications and use.

MSHA’s Approval and Certification Center has sole authority and responsibility to grant or withhold an approval. NIOSH’s role is to develop a

protocol for the conduct of sound safety and health science. Successful

completion of this project will produce a joint MSHA/NIOSH protocol

document for testing the locomotive to acceptable mining standards and

will yield the first documented tests of the noise and air quality performance of a fuel cell-powered mining vehicle. Hydrogen safety will also be

thoroughly investigated.
Spokane and Pittsburgh Research Laboratories

20 Office for Mine Safety and Health Research

Young miner using mercury to separate gold in

Venezuela.

CHEMICAL HAZARDS IN MINING AND

PROCESSING

RESEARCHER: Pamela L. Drake

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining, dust,

airborne contaminants

BIBLIOGRAPHY

Drake PL [1998]. Controlling

occupational exposure to mercury. Presentation at the Mercury Assessment Workshop

(Zacatecas, Mexico, February

24-27, 1998).

Drake PL, Reh CM, Rojas M

[1998]. Assessing occupational

exposure to mercury in the gold

mining area of Bolivar State,

Venezuela. Presentation at the

Univ. Nat. Exper. de Guayana

(Puerto Ordaz, Venezuela, July

21-31, 1998).

Drake PL, Reh CM, Rojas M,

Jenkins FM [1999]. Assessing

occupational exposure to mercury in El Callao, Venezuela. 

Presentation at the 5th International Conference on Mercury

as a Global Pollutant (Rio de

Janeiro, Brazil, May 23-28,

1999).

PURPOSE: Investigate and evaluate potential chemical

hazards in mining workplaces to enable development of

control or mitigation methods.

RESEARCH SUMMARY: Exposure to metals and other

chemicals in mining workplaces, particularly in milling and

refining facilities, may adversely affect thousands of

workers. Mercury and silver are examples of potentially hazardous metals

found in ore deposits in the Western United States. 

Occupational exposure to silver and mercury can occur during

numerous refining processes. Dust containing mercury or silver can be

stirred up while handling dry concentrates and while cleaning silver bars

(doré bars) after smelting. Also, metal fumes can be released when

concentrates are heated during retorting and during smelting. Mercury or

silver from the refinery can be spread to other areas on shoes or clothing. 

In addition, because mercury has a high vapor pressure, whenever ore

concentrates containing mercury are heated, the mercury is vaporized. 

Characterization of exposure to mercury vapor and silver dust and

fumes during refining is the focus of this project. Workplace evaluations at

precious metal mines will be conducted to collect information about the

mercury and silver exposure hazards associated with refinery operations. 

The protocol for evaluating the refinery operations at each mine will

consist of (but not be limited to) initial and followup site visits. The initial

site visit will be designed to assess mercury and silver exposures at a given

refinery; to collect information about the process, engineering controls, and

other interventions; and to evaluate qualitatively the presence of other

hazards. The followup site visit will consist of further mercury and silver

exposure assessments, an evaluation of the engineering controls and

interventions, and exposure assessments for other hazards present in the

refinery areas. The results of this project will include implementation of

engineering controls that minimize chemical exposures within the refinery

to protect the health of the miners.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 21

Transport of talc by tramlines generates dust.

EXPOSURE TO TOXIC SUBSTANCES IN DUST

AT NONMETAL MINES

RESEARCHERS: Patrick Hintz and 

Pamela L. Drake

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Trona, nonmetal dust, ore dust, dust

monitoring

PURPOSE: Assess exposures to toxic substances in ore dusts

and recommend engineering controls to limit worker exposures to these

substances.

RESEARCH SUMMARY: There are approximately 25,000 workers employed in nonmetal mines. The largest sources of dust at nonmetal mines

are drilling and blasting operations in underground mines and crushing

operations in surface mines and mills. Haulage traffic is a source of dust at

all locations. Although metals and other trace toxic substances can be

present in nonmetallic ores, the extent to which they occur in dust and

whether exposure levels constitute a hazard have not been studied extensively. Neither are the health effects of exposure to dusts in these mines

addressed under the current NIOSH mining safety and health research

program except where significant amounts of silica are present. Stakeholder input from a talc mine in Montana and anecdotal accounts from

workers in trona mines in Wyoming indicate there are concerns about

exposure to dust in nonmetal mines. 

 Existing literature on nonmetal mines pertaining to the occurrence of

toxic substances, exposure monitoring, and adverse health effects will be

reviewed. An inventory of the potential occurrence of toxic substances in

nonmetal ore bodies will be developed from assays of ore samples obtained

from previous studies or available mining company records. Dust

monitoring will be conducted at selected sites to estimate exposures. A

protocol for dust monitoring will be developed to evaluate the effects of

exposure to toxic substances in ore, mining method used, engineering

controls used, personal protection practices, and management and worker

attitudes. Consideration will be given to variability among commodities

and among individual deposits of a given commodity when estimating

exposures. Practices that generate dust will be identified and

recommendations will be made for engineering controls to reduce dust

production or ventilation to reduce dust exposures. 
Spokane and Pittsburgh Research Laboratories

22 Office for Mine Safety and Health Research

Chamber in the mine where toxic fume measurements are

conducted. The steel plates protect the chamber from

shrapnel produced by the detonation of the pipe bomb.

TOXIC FUMES FROM BLASTING

RESEARCHER: James H. Rowland

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

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

rate of 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

they detonate. 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. 

Over the past 30 years, blasters have switched from the use of high explosives to less expensive blasting agents such as ammonium nitrate/fuel

oil (ANFO) mixtures. ANFO generates more toxic fumes than high explosives, and there is no standard test to determine the quantities of toxic

fumes generated by blasting agents. Additionally, surface mines have

moved toward shooting larger blasts, which has caused new problems from

blasting fumes. These large blasts produce proportionately larger quantities

of fumes that take longer to dissipate. 

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 bore holes. Additionally, a variety of contaminants may be added to

the blasting agent to determine their effect on fumes generation.

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 working

to find solutions. Information generated by this research, combined with

the experience of industry, will allow blasters to design blasts that

minimize toxic fumes generation.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 23

Haulage truck

HAZARD DETECTION AND

WARNING DEVICES

HAZARD REDUCTION FOR SURFACE

MINING HAULAGE EQUIPMENT

RESEARCHER: Todd Ruff

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Surface

mining, hazard recognition,

haulage

BIBLIOGRAPHY

Ruff T, Hession-Kunz D

[1998]. Application of radiofrequency identification systems

to collision avoidance in

metal/nonmetal mines. 

Presentation at IEEE Industry

Applications Society (St. Louis,

MO, October 12-16, 1998).

PURPOSE: Investigate, evaluate, and develop tools to reduce haulagerelated accidents and injuries in surface coal and metal/nonmetal mines. 

The project addresses three issues: hazard recognition, economics of safety,

and operator training.

RESEARCH SUMMARY: In the past 5 years, powered haulage accounted for 43% of all fatalities in mining and was one of the top five

sources of injuries in surface mines. Inadequate training and inadequate

information regarding the work environment contributed to the majority of

these accidents. Through partnerships with industry and MSHA, solutions

to these problems will be investigated and introduced to the mining

industry. 

This project consists of three main tasks. The first addresses accidents

caused when haulage equipment operators were unaware of obstacles in the

blind spots of their machines and other sources of limited visibility. This

task will investigate existing technologies for collision avoidance and develop improved technologies if needed. Currently, radar, radio-frequency

identification, and intelligent video camera technologies are being developed and tested. The goal of the second task is to provide mine operators

with data to make informed decisions on choosing one work practice over

another on the basis of economics and safety. For example, a cost analysis

of end-dumping versus short-dumping has been completed. The third task

will investigate new methods of training haulage equipment operators in

safe driving practices and safe reactions to emergency conditions. 

Computer-based simulation and training methods are being studied.
Spokane and Pittsburgh Research Laboratories

24 Office for Mine Safety and Health Research

Load rate warning device being tested on

mobileroof support.

MOBILE MINING EQUIPMENT WARNING

SYSTEMS

RESEARCHERS: John Owens and Wayne Howie

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Coal mining,

load monitoring, mobile roof

supports

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,

1999). 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, 1999). 

Unionville, VA: System Safety

Society, pp. 554-563.

PATENT

Method and Apparatus for Load

Rate Monitoring, patent

application 

PURPOSE: Develop effective monitoring and control systems

to reduce mining equipment accidents and their associated death

and injuries resulting from poor operating practices. The

recently patented load-rate monitoring device will be adapted for

this purpose. The approach focuses on accident prevention over

that of accident survivability. 

RESEARCH SUMMARY: A device for monitoring and displaying loading rate on the legs of mobile roof supports (MRSs) in real time has been

developed and patented by NIOSH's Spokane Research Laboratory. The

purpose of this device is to alert miners to dangerous ground conditions

during pillar extraction operations in coal mines. In this project, the device

will be adapted to monitor critical operating parameters of mobile mining

equipment. Both dynamic measurements and instantaneous rates of change

of critical parameters will be used to provide an early warning to operators

so they can take corrective actions to prevent selected accidents involving

equipment. Later phases of the research will include identification of

control devices that could be activated automatically if the operator did not

take corrective action immediately or if such action were insufficient. 

The research will be performed in four phases. The first will involve

completing field tests and evaluating the load-rate monitoring device on an

MRS in a retreat mining section. The second phase will be to select mobile

equipment types to be studied according to criteria based on the probability

of protecting the greatest number of workers within resource limitations. 

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 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. Research will be conducted to define

a delay period between the time an alarm is triggered and the actual critical

point that will allow sufficient time for the operator to react and take corrective action.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 25

Miner operating a continuous mining machine using a remote control.

INVESTIGATE PROXIMITY DETECTION

AND COLLISION AVOIDANCE

RESEARCHER: Gary L. Mowrey

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Proximity

warning, mining, collision

avoidance, injury prevention,

hazard

BIBLIOGRAPHY

Schiffbauer WH [1999]. A

workplace safety device for

operators of remote-controlled

continuous mining machines. 

Amer J Indus Med 36(suppl 1):

69-71.

Steiner LJ [1999]. Predicting

system interactions in the

design process. Amer J Indus

Med Sep(suppl 1):58-60.

PURPOSE: Develop an electromagnetic-based

proximity warning system for miners operating remotecontrolled continuous mining machines.

RESEARCH SUMMARY: A major safety problem in underground coal

mining is that of personnel becoming permanently disabled or being killed

by machinery (average 40 per year) and powered haulage (44 per year). 

From 1992 to 1997, 24 fatalities were associated with continuous mining

machines. Mining machine operators and helpers, preoccupied with operating their equipment to mine coal, may unintentionally put themselves into

potentially hazardous locations. Based on such statistics, the Mine Safety

and Health Administration (MSHA) requested that the Pittsburgh Research

Laboratory develop a proximity warning system (called “HASARD” -

Hazardous Area Signaling and Ranging Device). This system warns miners

if they are unknowingly putting themselves into a possible pinning or

crushing scenario, thereby helping to reduce the occurrence of such

incidents.

The HASARD system consists of two main components: a transmitter

that is mounted on a continuous miner (CM) and a receiver worn on the

belt of each worker. The transmitter injects a 60-kHz sinusoidal wave into

one or more wire loops fastened around the perimeter of the CM. Each

worker’s receiver has a set of six orthogonally mounted ferrite core antennas that measure the resultant magnetic field and compare this measurement against two present levels, calibrated to identify levels of risk to the

workers near the CM.

To determine the practicality of this device in an active mining environment, a series of technical and human factors field experiments using

the HASARD system are being conducted at an underground coal mine. 

Such in-mine testing will provide valuable information for optimizing this

system in the mine environment. This system is expected to significantly

reduce injuries and fatalities related to pinning and crushing incidents. It

could also be modified for protecting workers in other industries, such as

agriculture, construction, and forestry.
Spokane and Pittsburgh Research Laboratories

26 Office for Mine Safety and Health Research

Roof bolter

ADVANCED WARNING OF GROUND STABILITY

HAZARDS

RESEARCHERS: Steve Signer and Lewis Martin

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Underground

mining, ground stability,

monitoring instruments 

BIBLIOGRAPHY

McHugh E, Signer SP [1999]. 

Roof bolt response to shear

stress: laboratory analysis. In:

Proceedings of the 18th International Conference on Ground

Control in Mining. Morgantown, WV: West Virginia

University, pp. 232-238.

Signer SP, Lewis JL [1998]. 

A case study of bolt performance in a two-entry gate road. 

In: Peng SS, ed. Proceedings of

the 17th International Conference on Ground Control in

Mining. Morgantown, WV:

West Virginia University, 

pp. 249-256.

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: MSHA statistics indicate that there is a dire

need to warn underground miners of unexpected ground stability hazards. 

Although previous research studies conducted through NIOSH and the

former U.S. Bureau of Mines have demonstrated that geotechnical

instruments can be effectively used to identify and monitor ground control

hazards in underground mines, 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. Innovative methods will be

investigated for supplying power for electronic measurements through a

remote cableless input signal. A prototype miniaturized data acquisition

system will be developed that can measure strain gauges remotely without 

long lead wires. 

Gauge design will be reviewed to develop a more practical instrument

for monitoring rock strains. This sensor will measure plane strain and

detect shear movement along the length of the sensor. Hazardous levels of

horizontal, vertical, and shear strain that lead to rock failure will be detected so that a warning signal can be given and corrective action taken.

Data from more than 100 instrumented roof bolts and cable bolts installed at more than 10 mine test sites will be analyzed. Effects of geology,

geometry, and in situ stress fields will be studied, and conditions that cause

rock support failures will be identified. Standards for hazardous strain

levels that indicate excessive loading of rock supports will be established.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 27

Ford F800 single axle dump truck undergoing tests

at Lake Lynn Laboratory.

OVERHEAD POWER LINE CONTACT ALARM

FOR MOBILE EQUIPMENT

RESEARCHER: James C. Cawley

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining, electrocution, power line, alarm,

crane, truck

BIBLIOGRAPHY

Hinze J [1966]. Analysis of

fatalities and injuries due to

power line contacts. J Constr

Eng and 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 (IAS) 1999 Annual Meeting (October 4, 1999).

PURPOSE: Reduce the incidence of electrical injuries that occur when

mobile equipment accidentally comes into contact with overhead power

lines by devising a means to warn vehicle operators and nearby support

personnel of line contact.

RESEARCH SUMMARY: Overhead electric power lines are a serious

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

industry. From 1980 to 1997, at least 106 mobile equipment overhead line

contact incidents were reported in the U.S. mining industry, causing 106

injuries, of which 30% were fatal. Most involved cranes (39%), dump-bed

trucks (22%), and drills (13%). The widespread use of a reliable overhead

power line contact alarm on mobile equipment would reduce the number of

injuries and fatalities from equipment-line contacts. A practical contact

alarm would also have a significant impact in other industries where

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

communications, and public utilities. 

The question to be addressed is whether electrical currents flowing

through a vehicle in contact with a high-voltage source can be practically

detected and trigger an alarm. The alarm would then warn the operator and

bystanders 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 may be detected by either current or

voltage-sensing methods; both will be explored. Operator safety during an

overhead power line contact accident requires all surfaces in the operator

compartment and in the path used to exit the vehicle to be at the same electrical potential. Voltage differences between surfaces in the operator cab

and along the egress path will be measured to determine whether lethal

voltage differences exist. Depending on the preferred method of detection

and the results of the other test phases, a prototype device will be constructed and subjected to laboratory tests to verify its performance.
Spokane and Pittsburgh Research Laboratories

28 Office for Mine Safety and Health Research

Accelerometers

INVESTIGATION OF ELECTROMAGNETIC

PRECURSORS TO ROCK BURSTING

RESEARCHER: Doug Scott

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

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 I 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 II will proceed if the data analysis from the Phase I research proves that

this method is useful and reliable in detecting imminent ground failure in underground mines. Phase II 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 29

Coal fire detection experiment in the Safety

Research Coal Mine.

SMART FIRE SENSORS

RESEARCHER: John C. Edwards

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

PURPOSE: Examine new and improved mine fire detection

technologies and develop strategies for ensuring the safety of

underground mine workers.

KEYWORDS: Fires, mining,

detection, sensor systems

BIBLIOGRAPHY

Edwards JC [1997]. Overview

of mine fire detection. In: Proceedings of the Second International Conference on Fire Research and Engineering (Gaithersburg, MD, August 3-8,

1997), pp. 489-499.

Edwards JC, Hwang CC [1999]. 

CFD analysis on mine fire

smoke spread and reverse flow

conditions. In: Tien JC, ed. 

Proceedings of the Eighth U.S.

Mine Ventilation Symposium. 

Rolla, MO: University of

Missouri-Rolla Press, pp. 417-

422.

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 Eighth U.S.

Mine Ventilation Symposium. 

Rolla, MO: University of

Missouri-Rolla Press, pp. 295-

301.

RESEARCH SUMMARY: The early and reliable detection of underground mine fires is important for the safety of miners in their workplace. 

Existing products of combustion (POC) mine fire sensors, as well as reliable POC sensors currently not used in underground mines, 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 cross-interference effects from battery-charging

stations 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 within 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. The in-mine research

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

fires, and flaming diesel fuel fires. Chemical cell and metal oxide

semiconductor gas sensors, and ionization and optical smoke sensors

provide the matrix of sensors for sampling the POC downwind from the

fire. This research is being supported by modeling applications of a computational fluid dynamics computer program and a mine fire ventilation

computer program. Predictive modeling can provide guidelines to the fire

signature and its rate of change at a smart fire sensor location. A partnership with a coal mine is being established for an in-mine evaluation of new

fire sensor technology. This research will be conducted in cooperation

with the Mine Safety and Health Administration, sensor manufacturers, and

mine operators.
Spokane and Pittsburgh Research Laboratories

30 Office for Mine Safety and Health Research

Solar panel generates energy for

monitoring seismic activity in the

mountains.

GROUND STABILITY ASSESSMENT WITH SEISMIC

MONITORING

RESEARCHER: Peter Swanson

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Rock bursts,

coal bumps, mine collapse,

mining-induced seismicity, rock

mechanics

BIBLIOGRAPHY

Swanson PL [1999]. 

Investigation of a largescale catastrophic collapse

in a Wyoming trona mine. 

In: Proceedings of the 28th

International Conference of

Safety in Mines Research

Institutes (Sinaia,

Romania). Vol. I, pp. 343-

358.

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, and massive pillar

failures 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 have the potential to affect an entire

underground workforce. An inability to address these problems

effectively can result in resource abandonment and/or mine closure and 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. Field efforts are underway with industry partners in

hard-rock, coal, and trona mines. 

Development of a user-friendly, PC-based, automated seismicity

monitoring 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. At the Galena Mine, a specific goal is

to detect and locate sites of sudden mining-induced failure (rock bursts) in

the widely distributed working areas and to provide this information in real

time to supervisory and safety personnel stationed underground and on the

surface. As development of this technology continues, it will be applied in

other mines to address different types of ground control problems.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 31

Void created in surge pile.

DETECTION OF BRIDGING IN SURGE PILES 

RESEARCHER: Steve Iverson

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Surface mining, surge piles, bridging, voids,

collapse

PURPOSE: Investigate technologies to detect voids in coal surge piles.

RESEARCH SUMMARY: Bulldozers are used to move coal toward

drawpoints in surge piles at coal mines, which can be extremely hazardous

if a void forms within the pile because of bridging. Because voids are not

visible from the surface, a bulldozer or other piece of machinery could be

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

machine and injure or kill the operator. Seventeen 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

machinery was driven over it.

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

piles. One possible method is to combine real-time volume profiling near

feeders and measurements of the amount of volume drawn. Deviations between the amount of load measured in a chute and the amount of load expected would confirm that a void is forming.

Studies will also be conducted using particle flow code to model void

formation in surge piles. Coal samples will be collected to determine the

physical properties to be used in the models. Initial work has included

visits to surge pile sites, investigations of the use of global positioning

systems to track dozers and locate drawpoints, studies of surge pile design,

and evaluations of current mitigation measures used by the Mine Safety

and Health Administration and mining companies.
Spokane and Pittsburgh Research Laboratories

32 Office for Mine Safety and Health Research

Demonstration of improved scaling bar.

INJURY PREVENTION AND

EQUIPMENT DESIGN

SAFETY ENHANCEMENTS FOR ROCK SCALING

PERSONNEL

RESEARCHER: Grant King

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Materialshandling accidents, mining

equipment, rock falls, scaling

VIDEO: Rock Falls: Preventing Rock Fall Injuries in

Modern Mines

PURPOSE: Study present methods of scaling and their associated

safety risks and develop interventions that will reduce the number of

injuries caused by scaling-related accidents.

RESEARCH SUMMARY: Scaling, which is the removal of loose rock

from the walls and roof in an underground mine, may be necessary during any

stage of mining. Manual scaling is very labor-intensive, and mechanical

methods may actually produce less stable roof because the techniques used are

too intensive. MSHA data for the past 10 years indicate that 30% of the

fatalities in underground metal/nonmetal mines were related to failures of

ground. In addition, researchers noted that many otherwise classified accidents

could be linked to scaling processes, such as prying or barring down, or to

loose material falling. These injuries were often classified as “hit by rock” or

“strain/back injuries.” Thus, the process of scaling was identified as a major

source of injury to miners and was targeted for investigation.

The approach taken will be to assess current scaling methods and their

associated safety risks. This work will include first-hand observations,

discussions with mine workers and supervisors, and investigation of mine

accident data to identify specific problem areas. Then alternative scaling

methods, training materials, and equipment will be developed that allow miners

to free loose rock from a safe distance and reduce the use of brute force, which

is the source of many sprains, strains, and back injuries.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 33

Removing conveyor belt in an underground

mine.

MATERIALS HANDLING ACCIDENT REDUCTION IN

UNDERGROUND MINES

RESEARCHERS: Bill Stewart and Ted Williams

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Repetitive

trauma, materials handling,

manual rock breaking

PURPOSE: Improve methods and procedures to reduce or prevent

repetitive trauma and accidents associated with materials handling in

underground mines. 

RESEARCH SUMMARY: Repetitive trauma and materials-handling accidents continue to be a problem in underground mines because of limited

space, poor footing, inadequate materials-handling equipment, and the weight

and bulk of the materials themselves. For example, a search of the MSHA

database for the period between 1987 and 1996 identified 78 accidents out of

392 (20%) in underground metal/nonmetal mines as being due to breaking or

cleaning rock manually from the top of a grizzly. Another major cause of

accidents involved removing the belt conveyor frame and rollers during longwall operations in western underground coal mines. The rock and coal dust

under and around the belt is often wet, creating a very poor surface for maintaining one’s footing while removing heavy conveyor parts. Identifying stateof-the-art procedures for removing the structure and developing improved

engineering designs for the workplace may reduce the repetitive trauma and

accidents associated with this common job.

The approach taken in this project is to identify best practices in underground mines having low injury rates and then to transfer this information to

the rest of the industry. Engineering solutions to some common problems may

also be developed. MSHA accident statistics will be reviewed to identify underground mines with both very good and bad materials handling records. A

series of mine visits will be conducted to acquire an understanding of the general materials-handling approaches used in the various underground industries. 

The information gathered during the initial visits will then be used to focus the

project for the remaining 3 years. Possible focus areas might be creating a best

practice report after examining procedures at a large number of mines or developing engineering design solutions to one or two problem areas found to be

common throughout the industry, such as removing heavy conveyor parts and

manually breaking oversize rock on grizzlies.

In underground metal, nonmetal, and stone mines, it may be more difficult

to identify a single focus area because materials-handling equipment and

procedures vary greatly from mine to mine. However, nonmanual or

reduced-manual materials-handling methods will be the primary research

consideration at all mines. For some mines, a best practices handbook may

have the greatest impact for reducing injuries.
Spokane and Pittsburgh Research Laboratories

34 Office for Mine Safety and Health Research

Dropping load into haulage truck creates

impact shock for the truck operator.

ENGINEERING CONTROLS FOR REDUCING

JARRING AND JOLTING INJURIES IN SURFACE

MINES

RESEARCHERS: Fred Biggs and Rusty Miller

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Vibration,

shocks, haulage trucks, jolting,

jarring

PURPOSE: Devise and promote the use of engineering controls to

eliminate or 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. This increase has resulted in

larger haulage trucks, increased production demands, and more people in

the work force, which in turn has led to more worker fatalities and

injuries. Between 1986 and 1995, truck drivers accounted for 35

approximately 63% (76 of 120) of the fatalities in surface mining truck haulage

and 60% (3,551 of 5,569) of the lost-time injuries. Very little research has

been done related specifically to shock trauma injuries, that is, jolting and

jarring injuries caused by surface mine haulage trucks, nor to the development

of engineering controls to reduce such injuries. 

Tasks in this project include —

• Developing software for tying global positioning systems and jolting and

jarring incidences together.

• Conducting bench-scale tests to characterize and isolate jolting and jarring

elements that could lessen shock loads on an operator. 

• Defining current engineering controls used to minimize exposure to health

hazards and note their limitations.

• Testing various engineering control alternatives under laboratory conditions. Alternatives showing the greatest promise will be developed to the point

where they can be tested in the field. Current developments will be evaluated

to select technologies applicable to the surface mining environment.

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 35

Field interview with underground miners.

ERGONOMICS INTERVENTIONS IN MINING

RESEARCHER: Fred C. Turin 

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining,

ergonomics, musculoskeletal

disorders, slips and falls

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 [1995]. 

Exposure probabilities to

ergonomic hazards: II. National

occupational exposure survey

results for various industries and

general conclusions. In: Bittner

AC, Champney PC, eds. 

Advances in Industrial Ergonomics and Safety VII. London:

Taylor and Francis, pp. 287-296.

Zhuang Z, Groce D [1995]. The

national occupational 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: Taylor

and Francis, pp. 273-280.

PURPOSE: Assess ergonomic risk factors in select mining

environments. Develop, implement, and evaluate ergonomics

interventions.

RESEARCH SUMMARY: In early 1998, the Mine Safety and Health

Administration (MSHA) submitted a formal request to NIOSH to investigate

musculoskeletal disorders (MSDs) in the mining industry. MSHA

representatives wanted a better understanding of the extent of MSD risk factors

and evidence that ergonomics interventions are effective. An analysis of results

from the National Occupational Health Survey of Mining (NOHSM) indicated

that both coal miners and metal/nonmetal miners are exposed to a higher

number of ergonomic risk factors than workers in nonmining occupations. 

Miners experience more disability from knee and back pain, more absenteeism,

more osteoarthritis, and more disk degeneration than comparison industrial

populations.

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

risk factor assessments at select mining operations with emphasis on MSDs. 

The second phase involves development, implementation, and evaluation of

ergonomics interventions at cooperating mine operations.

Four mine sites are participating in risk factor assessments. They consist

of an underground coal operation, a surface copper operation, a surface

phosphate operation, and an underground limestone operation. Assessment

results are being used to identify activities that provide significant risk for

injury and to develop general risk reduction strategies. The primary benefit to a

cooperating mine operator is 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. 

A separate, but related investigation under this project involves the high

incidence of slips, trips, and falls in mining. From 1990 to 1997, 26,703 slips,

trips, and falls were reported, making this one of the largest categories of

lost-time injuries. The research involves a comprehensive literature review,

analysis of surveillance data, and field investigations to assess injury risk. 

Intervention strategies are being developed and evaluated in the field.
Spokane and Pittsburgh Research Laboratories

36 Office for Mine Safety and Health Research

A lighter jackleg drill could reduce injuries

among drill operators.

INJURY PREVENTION FOR METAL/ NONMETAL

DRILLING AND BOLTING OPERATIONS

RESEARCHERS: Robert McKibbin and

Curtis Clark

AFFILIATION: Spokane Research Laboratory

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining, low

back disorders, materials handling, jackleg, drilling safety

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: MSHA-based statistics show that during

the 5-year period of 1992-96, there were 10 fatalities and more than

1,000 injuries in drilling and bolting operations in metal/nonmetal

mines, accounting for 5% and 4% of all fatalities (233) and injuries (25,693),

respectively, in those years. During the first year of this project, investigators

highlighted a number of areas in which reductions in accidents might be realized. These included crushing injuries on carriage and jumbo drills, getting

caught in rotating drill components, excessive weight of jacklegs, slips and falls

while getting on/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 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 a lightweight jackleg. The goal is to reduce the weight to 77 pounds

without a reduction in the specific energy of drilling. A drill was constructed in

which several components were made of aluminum and titanium, resulting in a

drill that is 25% lighter than a standard steel drill. Laboratory testing of the

drill was started in late FY99 and will continue in FY2000, followed by

in-mine testing. 

Background research will be ongoing and will be augmented by discussions with various segments of the mining community, including miners, mine

managers, engineers, safety officers, equipment manufacturers, and union

representatives. Additional work in the future could include further weight

reduction of the jackleg, a reduced-vibration jackleg handle, design

modifications to prevent being caught in rotating components, a modular

add-on to an existing piece of machinery, design recommendations to equipment manufacturers, or procedural changes based on results of human factor

evaluations.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 37

Computer simulation assists in the investigation of safe

boom speeds for roof bolter operators.

HUMAN FACTORS DESIGN FOR MACHINE

AND HAULAGE SAFETY

RESEARCHER: August J. Kwitowski

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining equipment, ergonomics, intervention,

vibration, machine design, safety

BIBLIOGRAPHY

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, Gallagher S, Merkel

R [1997]. Ergonomic seat with

viscoelastic foam reduces shock

on underground mobile

equipment. In: Das B, Karwoski

W, eds. Advances in

Occupational Ergonomics and

Safety II. IOS Press and Ohmsha:

pp. 177-180.

Mayton AG, Merkel R, Gallagher

S [1998]. Shock reduction for

low-coal shuttle car operators

using viscoelastic seating foam. 

SME preprint 98-44. Littleton,

CO: Society for Mining,

Metallurgy, and Exploration, Inc.

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

working near mining equipment.

RESEARCH SUMMARY: Mining machinery continues

to be linked with numerous fatalities and injuries. From 1993 to 1996, analysis

of underground coal mining machinery injury data shows that the fatality rate

was 0.0374 (rates are incidences per 200,000 hours); the nonfatal injury rate

was 6.833. During 1997, 32% of all injuries to underground coal miners

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

activities. Nineteen percent of these injuries were from equipment design

problems. In addition, the broad injury categories of mining machinery and

powered haulage are prevalent across all commodities in surface and

underground mining.

The overall approach is to identify specific mining 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. Two specific machine problems are currently being investigated: safe roof bolter boom speed, and the jarring and jolting of mobile

equipment operators. The roof bolter research involves the use of computer modeling/simulation in addition to laboratory and field experimentation

to study the problem and develop recommendations for safe boom speeds. 

A major roof bolting manufacturer is collaborating on this research. The

operator vibration/seating research involves computer modeling, the Pittsburgh Research Laboratory’s vibration testing facility, and laboratory and

field research. Both improved seating and alternative suspension systems

are being evaluated for isolating the operator from excessive jolting. A major shuttle car manufacturer and a mining seat manufacturer are cooperating on the jarring and jolting research. This project is producing design

guidelines and better hardware for mining equipment hazards through

cooperation with equipment manufacturers and mining companies to improve equipment safety.
Spokane and Pittsburgh Research Laboratories

38 Office for Mine Safety and Health Research

Underground coal mine workers may be electrically

shocked when handling portable power cables with 

defective insulation.

FUNDAMENTAL STUDIES IN ELECTRICAL

HAZARDS

RESEARCHER: Michael R. Yenchek

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Electrical

shock, arcing, burns, mining,

construction, safety

BIBLIOGRAPHY

Li J, Kohler JL [1999]. New

insight into the detection of

high-impedance arcing faults on

dc trolley systems. IEEE Transactions on Industry Applications 35(5):1169-1173.

Oommen MP, Kohler JL

[1999]. Effect of three-winding

transformer models on the analysis and protection of mine

power systems. IEEE Transactions on Industry Applications 35(3):670-674.

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 the 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 areas such as lightning protection, an area in which

there is concern because of lightning-initiated gas explosions in gob areas

of the mine.

This research is identifying, analyzing, and classifying the causes of

electrocutions across industries according to established categories, e.g.,

voltage class, source, exposure, etc. This information is being used to

determine the type of interventions that could prevent future occurrences,

such as training, personal protective equipment, and design. Available

intervention technologies are being reviewed to identify any gap areas. 

Finally, recommendations for specific actions to reduce fatalities are being

formulated.

In addition, specific technologies to mitigate electrical hazards are

being examined. For example, analyses of hazards on high-voltage

longwall power systems, lightning-initiated gas ignition hazards, and

temporary wiring hazards at construction sites are being conducted to

quantify the hazard and assess the appropriateness of certain control

strategies.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 39

Improved sensors to monitor hoist

conditions could lead to safer operating

conditions.

MINE HOIST AND ELEVATOR SAFETY

RESEARCHER: Michael J. Beus

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mine hoisting,

wire rope tension, conveyance

monitoring, wireless data

transmission

BIBLIOGRAPHY

Beus MJ, Iverson S [1999]. Safer

mine hoisting with conveyance position and load monitoring. Amer J

Ind Med. Suppl 1:119-121.

Beus MJ, Ruff TM, Iverson S, Hasz

W, McCoy WG [1999]. Mine shaft

conveyance monitoring. SME preprint 99-83. Littleton, CO: Society

for Mining, Metallurgy, and Exploration, Inc.

NIOSH [1998]. Technology news

469: sensors warn of hazards

during mine hoisting. 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.

PATENT

No. 5,728,953. Flex-Beam Load

Cell.

PURPOSE: Improve the safety of hoist and elevator operations by using

sensor and computer technology to increase the amount of information and

efficiency of flow to hoist operators and inspectors.

RESEARCH SUMMARY: This project was initiated at the request of

MSHA because of increasing concern about hoist and elevator safety. According to accident statistics, mine hoist maintenance workers and hoist

operators are exposed to many hazards in hoisting environments. MSHA,

mine hoist operators, and maintenance personnel have expressed an

interest in better technology to monitor these hoist conditions. 

A state-of-the-art hoisting and ore pass research facility has been constructed. This facility allows assessment of mine hoisting and elevator

safety and control systems, including hoisting machinery (hoist room controls, motors and gear boxes, and winders) and shaft infrastructure (support

frameworks, guides, wire ropes, and skips and cages). Sensors and realtime data acquisition interfaces to monitor hoisting operations have been

developed. These systems allow personnel to assess critical hoist operating

parameters, such as hoist position, speed, and acceleration; conveyance

loads; rope tension; and shaft guide alignments. A load cell has been developed to measure rope tension and has been patented. Field work to

evaluate the performance of these systems is underway in cooperation with

mine hoist equipment suppliers and mining companies.
Spokane and Pittsburgh Research Laboratories

40 Office for Mine Safety and Health Research

Loosening blockages in ore passes can be extremely

hazardous.

DESIGN OF MINE ORE PASSES

RESEARCHERS: Michael J. Beus and Bill Stewart

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Ore pass, field

measurements, computer analysis, materials handling, ground

control

BIBLIOGRAPHY

Beus M, Iverson S, Stewart B

[1998]. Design analysis of

underground mine ore passes: 

current research approaches. 

Presentation at the 100th CIM

Conference (Montreal, Quebec,

Canada, May 3-7, 1998).

Beus M, Iverson S,

Dreschler A, Scott V [1999]. 

Static and dynamic loads in ore

and waste rock passes in

underground mines. In: Rock

Mechanics for Industry. 

Proceedings of the 37th U.S.

Rock Mechanics Symposium

(Vail, CO, June 6-9, 1999). 

Balkema, pp. 489-495.

PURPOSE: Improve ore pass design criteria to prevent

hangups and structural failures and investigate safe

procedures for removing hangups. Develop enabling

technology for detecting and remediating blockages in ore

passes in hard-rock mines. 

RESEARCH SUMMARY: Research on ore pass designs

will include measurements of static and dynamic loads,

predictions of loads using particle flow models, studies of

the influence of ore pass inclination on loading, tests of

innovative methods to determine fill levels and hangup locations, and

development of safer hangup removal methods. 

Because of the relationship between hangups and the physical

properties of ore and rock, physical models will be tested at SRL’s shaft

and ore pass test facility. Special emphasis will be placed on investigating

the role of moisture content, the fine grain-size fraction, and stop-and-go

ore movement on cohesion-type hangups. Hangup removal methods will

also be tested, and the effects of ore hangups on the structural integrity of

the test facility will be examined. Various designs of ore pass structures

will be simulated in computer models. Such information will aid mine

engineers in designing safer ore passes and increase miner awareness of

proper hangup removal procedures.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 41

Filming a video to show safe mining practices.

TRAINING AND EDUCATION

INTERACTIVE TRAINING AND EDUCATIONAL

DEVELOPMENT

RESEARCHERS: Elaine Cullen, Marc Filigenzi,

and Timothy Orr

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining, safety

training, computer visualization

VIDEO

Handling Explosives in Underground Mines

PURPOSE: Develop multimedia training tools that can be used to

provide safety training to miners.

RESEARCH SUMMARY: A NIOSH study on occupational deaths

between 1980 and 1989 indicate that, in the mining industry, the average

annual fatality rate is 31.9 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 will serve as an advisory board to assist in determining topics

and issues, assist in assuring that story boards and scripts are technically

correct and relevant to trainees, and assure that mine sites are available to

show the topics under consideration effectively. This advisory board will

also be used to 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

42 Office for Mine Safety and Health Research

Pilot test of new computer-based training module

on proper use of machine guards.

EVALUATION OF INTERACTIVE MINE SAFETY

AND HEALTH TRAINING METHODS

RESEARCHER: Robert F. Randolph

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining, intervention, training, effectiveness

BIBLIOGRAPHY

Brnich MJ Jr., Vaught C, Calhoun

RA [1999]. I can’t get enough air:

proper self-contained self-rescuer

usage. 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.

99-160.

Rethi LL, Flick JP, Kowalski KM,

Calhoun RA [1999]. Hazard recognition training program for construction, maintenance, and repair

activities. 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. 99-158.

Rethi LL, Wiehagen WJ, Calhoun

RA, Garry D, Cole HP, Brnich MJ

Jr. [1999]. Investigation of a slip/

fall accident. 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.

99-156.

PURPOSE: Determine the real-world effectiveness of a variety of lowand 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 increased efficiencies available through these technologies offer better results from the scarce resources available. 

Prototype interactive training systems are being 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 successful field evaluation of an interactive construction, maintenance, and repair exercise was recently completed through mining industry

cooperation. The project team is also conducting a cooperative project with

a mine in Colorado to evaluate the special needs of an anticipated influx of

younger, inexperienced workers and to develop cost-effective training

tailored to specific worksites. Building upon the latent-image hazard recognition effort, content has been selected for prototype computerized applications, and an initial working version has been completed.

Another project goal is improving 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 13,000 training

items since January 1999.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 43

Screen shot of fire and smoke in simulated underground

coal mine.

EDUCATION FOR EFFECTIVE MINE

EMERGENCY RESPONSE

RESEARCHER: Launa G. Mallett

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Training, simulation, emergency response, command

center, fire prevention

BIBLIOGRAPHY

Mallett LG, Brnich MJ Jr. [1999]. 

Focus on prevention: conducting a

fire risk assessment. 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. 99-155.

Mallett LG, Brnich MJ Jr., Vaught

C [1998]. Training to improve

emergency communication skills. 

In: Proceedings of The International Emergency Management Society

(TIEMS) Conference (Washington,

DC): pp. 471-476.

Mallett LG, Vaught C, Brnich MJ

Jr. [1999]. The emergency communication triangle. 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. 99-157.

PURPOSE: Reduce the risks associated with infrequent,

but potentially catastrophic, mine emergencies by

developing training materials for first responders and

command center personnel. 

RESEARCH SUMMARY: As mines become safer and

disasters fewer, the number of individuals that have hands-on experience

with mine emergencies is decreasing. A gap in expertise is being created

that could have serious consequences at future major emergency events. 

Because potentially catastrophic hazards are not faced routinely, emergency prevention and response is sometimes given a low priority in training

plans. Training for command center leaders is not mandated, and most

managers have little or no experience with mine emergencies. Although

some training is available to the mining industry, it can be expensive to

conduct and/or not easily accessible to all mining operations.

The goal of this project is to reduce the risks associated with infrequent, but potentially catastrophic incidents by improving prevention and

emergency response training (and access to that training) for miners, incident responders, and command center personnel. Methodologies and

training packages are being developed to teach prevention and firstresponse strategies. These materials and strategies will meet the need for

training in limited timeframes. Software is being developed to teach

command center leaders to coordinate and manage response efforts via

computer simulation. This customizable software will allow emergency

response experts (including State and Federal agencies) to develop new and

varied training scenarios. Delivered via the Internet, this training will be

accessible to all U.S. mining operations. The products of this project will

be applicable, with some modification, to all mining worksites. Some of

the results will also be useful for emergency training in other types of work

settings. 

Project activities are being conducted in cooperation with staff at two

underground coal mines (one in Colorado and one in Pennsylvania), the

Mine Safety and Health Administration, and the State mining agency in

Pennsylvania.
Spokane and Pittsburgh Research Laboratories

44 Office for Mine Safety and Health Research

Use of virtual reality is being studied to improve mine safety training.

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

1-800-35-NIOSH

KEYWORDS: Mining, hazard

recognition, rescue and evacuation training

BIBLIOGRAPHY

Filigenzi MT, Orr TJ, Ruff TM

[1998]. Computerized accident

reconstruction and training for

metal/nonmetal mines. Presentation and extended abstract in:

7th Annual NIOSH-FIOHNIWL Scientific Symposium

(Morgantown, WV).

PURPOSE: Develop computer visualization techniques

that can be used to reconstruct accident sites on the computer accurately so

that employees can be informed of the hazards in underground mines. Use

these techniques to develop models of underground mines as part of a training program to teach hazard recognition and evacuation and rescue procedures to new employees.

RESEARCH SUMMARY: Current information dissemination and training methods are lacking in that they depend on training videos and/or

printed materials that are not specific to each mine and that are often

outdated. Mine evacuation drills are expensive and time-consuming and

cannot be practiced at regular intervals. New ways are needed to train

personnel about hazards in mining workplaces and about evacuation procedures. By improving safety training, researchers hope to increase worker

safety and reduce work-related accidents. Two tasks are being addressed.

Accident Reconstruction. In mining, injuries or death may result from equipment failure or worker 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 to absorb. 

As a result, mining personnel may not learn exactly which hazardous situation to be on guard against. The purpose of this task is to develop computer

modeling and visualization techniques that will allow accident investigators

to re-create an accident on a computer accurately. This re-creation can then

be used as an educational tool. Employees will view a computer-generated

animation showing the cause and results of the accident. They will then be

shown the proper way to avoid such accidents in the future. 

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 in deep multilevel mines will

be investigated. Existing software technology will be applied to create

realistic three-dimensional representations of a mine environment. Mine

trainees will then be immersed in this “virtual mine” in which emergencies

are simulated. The trainees will then practice escape and rescue procedures. This same virtual mine will be used to train employees in hazard

recognition and avoidance. 
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 45

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

1-800-35-NIOSH

KEYWORDS: Fires, mining,

preparedness, emergency responders, mine rescue training

BIBLIOGRAPHY

Conti RS, Weiss ES [1998]. 

Inflatable devices for combating

underground mine fires. In:

Proceedings of Minesafe International 1998. University of

Witwatersrand, Republic of

South Africa, pp. 388-393.

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.

PURPOSE: Develop realistic training simulations for responders to mine emergencies and evaluate technology that

can be used during exploration and firefighting.

RESEARCH SUMMARY: Unfortunately, fires remain a common occurrence

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

Administration (MSHA) reported more than 130 fires at underground coal

mines (fires lasting more than 30 minutes after discovery or causing injury). 

These fires resulted in 1 fatality and 43 injuries. A significantly higher number

of unreported fires are believed to have 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 may 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 survey conducted by MSHA indicated that there are 281 State and

company mine rescue teams in the United States (124 coal mine teams and

157 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 has decreased. 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. 

During the last year, partnerships were established with one coal company,

the Pennsylvania Bureau of Deep Mine Safety, and the West Virginia Office of

Miners’ Health, Safety, and Training to evaluate their mine rescue teams. Data

have been collected from five mines in Colorado, Illinois, Montana, Pennsylvania, and Utah to determine their fire preparedness and response capabilities. 

Interviews with mine rescue teams and fire brigade members during training

simulations at Lake Lynn Laboratory and at operating mine sites 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. An underground mine fire preparedness and response

checklist, which is currently being developed for coal and metal/nonmetal

mines, is intended to enhance the safety of mine workers by improving the state

of fire preparedness at underground mines.
Spokane and Pittsburgh Research Laboratories

46 Office for Mine Safety and Health Research

Operator’s station inside mobile

audiometric test unit.

INTERVENTION THROUGH EDUCATION AND

TRAINING TO PREVENT HEARING LOSS AMONG

MINERS

RESEARCHER: David C. Byrne

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

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

hearing loss among miners nationwide.

RESEARCH SUMMARY: Noise is one of the most pervasive health

hazards in mining. Exposure to high-intensity sound levels results in the

development of noise-induced hearing loss, which can be a serious

physical, psychological, and social problem. The overall goal of this

project is to educate miners regarding hearing conservation measures and

train them to recognize ways that they may assist in hearing loss prevention. Initial emphasis has been placed on techniques that can be quickly

implemented while reaching as many miners as possible. A pilot study

involving mine inspectors from the Mine Safety and Health Administration

(MSHA) and students was conducted at MSHA’s National Mine Health

and Safety Academy, Beaver, WV, from March to June 1999. Different

combinations of intervention techniques and strategies were examined for

their usefulness, efficiency, and practicality. 

Successful intervention methods will be further tested and disseminated

more widely, perhaps instituting a “train the trainer” approach that will

perpetuate itself throughout all mining sectors. With this approach, one or

more persons from each mine site could be trained to become the on-site

“expert” or source of information for fellow miners. In this manner, the need

for proactive hearing conservation measures will be continuously reinforced.

The education and training of selected mining populations relies on site

visits by a fully functional mobile audiometric test unit. An important element of the project is to conduct hearing tests on noise-exposed miners,

which personalizes the problem and forms the basis for the educational aspects of the intervention. Similarly, individual fit-testing of personal hearing protection (e.g., earplugs or earmuffs) is done on each miner. Each

participant is shown a hearing loss demonstration via a multimedia computer program. The best use of these different elements will be refined and

updated as the project progresses. To this end, questionnaires, individual

interviews, and posttraining surveys are used to collect data on miners’

attitudes, behaviors, and knowledge toward hearing conservation.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 47

Collecting data on mine stability for entering into

computer model.

GROUND CONTROL

SAFETY DESIGN FOR UNDERGROUND MINE

STABILITY

RESEARCHERS: Mark Larson, Jeff Johnson,

and Eric Zahl

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Underground

mining, ground stability, modeling

BIBLIOGRAPHY

Johnson J, Brady T, Larson M, Langston R, Kirsten H [1999]. Use of

strain-gauged rock bolts to measure

rock mass strain during drift development. In: Rock Mechanics for

Industry. Proceedings of the 37th

U.S. Rock Mechanics Symposium

(Vail, CO, June 6-9, 1999). 

Balkema, pp. 497-502.

Johnson JC, Larson MK, Brady TM,

Whyatt JK, Langston RB, Kirsten H

[1999]. Stress measurement of a

jointed rock mass during drift development. In: SARES 99: 2nd South

African Rock Engineering Symposium (Johannesburg, Republic of

South Africa, September 13-15,

1999). International Society of Rock

Mechanics, pp. 94-101.

Maleki H, Zahl E, and Dunford J

[1999]. A hybrid statistical-analytical

method for assessing violent failure in

U.S. coal mines. In: 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, pp. 139-144.

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: Over the last 10 years, 30% of the mine

fatalities in underground metal/nonmetal mines and 44% of the fatalities in

underground coal mines were caused by failures of ground. Thus, 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

engineering tools for the design and analysis of stability in underground

mines through the use of personal computers.

Cooperative arrangements to investigate the stability of underground

mines and develop new instruments and techniques to measure and monitor

stability have been developed with several industry partners. The Stillwater Mining Co., Montana Tech, and the Spokane Research Laboratory

have entered into an agreement to investigate how a stability analysis can

best be integrated into the design of an expansion at the Stillwater Mine

and address a number of safety concerns. At the Homestake Mine, the

Ross shaft pillar is being analyzed for stability. Cooperative work with

RAG (formerly Cyprus Plateau Mining Co.) is directed to methods of

installing and monitoring instruments and analyzing the resulting data to

determine the potential for ground falls, coal bumps, and other types of

rock mass failures.

The results of this research will help predict the potential for ground

falls and coal bumps and allow miners to select appropriate secondary

support systems or restrict access to a particularly hazardous area, thereby

reducing accidents, injuries, and fatalities.
Spokane and Pittsburgh Research Laboratories

48 Office for Mine Safety and Health Research

Underground limestone mine portal.

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

1-800-35-NIOSH

KEYWORDS: Mine worker, underground stone, falls of ground,

safety, monitors, horizontal stress,

mine planning

BIBLIOGRAPHY

Iannacchione AT [1999]. Pillar

design issues for underground

stone mines. In: Peng SS,

Mark C eds. Proceedings of the

18th International Conference on

Ground Control in Mining.

Morgantown, WV: West Virginia

University, pp. 271-281.

Iannacchione AT, Dolinar DR,

Prosser LJ Jr., Marshall TE, Oyler

DC, Compton CS [1998]. 

Controlling roof beam failures from

high horizontal stresses in

underground stone mines. In: Peng

SS, ed. Proceedings of the17th

International Conference on

Ground Control in Mining,

Morgantown, WV: West Virginia

University, pp. 102-112.

Iannacchione AT, Prosser LJ Jr.,

Grau RH III, Oyler DC, Dolinar DR,

Marshall TE, et al. [1999]. Preventing injuries caused by unrecognized stone mine roof beam

failures with a proactive roof control

plan. SME preprint 99-87. Littleton, CO: Society for Mining,

Metallurgy, and Exploration, Inc.

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: Injury statistics from the Mine Safety and Health

Administration (MSHA) show that about 80% of the lost days and 20% of the

accidents in the underground stone sector were attributed to falls of ground. In

the nonmetal underground mining sector, falls of ground also represent a

significant portion of injuries. More than 10% of the accidents and 25% of the

total lost days were attributed to falls of ground in the nonmetal underground

mining sector. The underground stone/nonmetal sector employs approximately

6,000 miners. Although the need to initiate research to reduce ground falls in

underground stone and nonmetal mines is surveillance-based, this effort is also

strongly supported by stakeholders, including MSHA, State and national

mining organizations, (e.g., Kentucky Crushed Stone Association, Ohio

Aggregates and Industrial Minerals Association, and National Stone

Association).

It must also be noted that stone and other industrial minerals (i.e., nonmetals)

are the basic raw materials used in construction that drives economic development

nationwide. These sectors are expected to continue to expand in line with the

thriving U.S. economy. Constraints to surface mining and the availability of

resources are increasing the development of underground stone mines. Thus, the

likelihood and severity of incidents involving mine workers in this sector may also

increase without preventive measures. As such, expanded research efforts in this

area will help to improve safety conditions of mine workers employed in these

sectors today and in the future.

The intervention strategy used in this project is rooted in the fostering of

communication among the principals. The focal point is an annual safety

seminar, the only national meeting directed entirely toward this segment of

mining. This seminar provides a forum for the exchange and discussion of

issues related to the safety and health of the mine worker. In addition, roof

behavior awareness has been enhanced through the development of the Roof

Monitoring Safety System (RMSS) that is, in varying degrees, used at mines in

Pennsylvania, Kentucky, Indiana, and Illinois. Lastly, a safe mine layout for

minimizing roof rock damage from elevated horizontal stress levels is being

evaluated at a cooperating underground stone mine.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 49

Area extensively damaged by rock burst in hard-rock

mine.

IDENTIFICATION AND CONTROL OF ROCK

BURST HAZARDS 

RESEARCHERS: Jeffrey K. Whyatt, 

Brian G. White, and

Ted Williams

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Ground control,

rock bursts

BIBLIOGRAPHY

White BG, Whyatt JK [1999]. 

Differential wall rock movements

associated with rock bursts, Lucky

Friday Mine, Coeur 

d’Alene Mining District, Idaho. In:

Rock Mechanics for Industry. 

Proceedings of the 37th U.S. Rock

Mechanics Symposium (Vail, CO,

June 6-9, 1999). Balkema, pp.

1051-1059.

White BG, Whyatt JK [1999]. 

Role of fault slip on mechanisms of

rock burst damage, Lucky Friday

Mine, Idaho, USA. In: SARES 99: 

2nd South African Rock Engineering Symposium (Johannesburg,

Republic of South Africa, September 13-15, 1999). International

Society of Rock Mechanics,

pp. 169-178.

Whyatt JK, Blake W, Williams TJ

[1997]. Classification of large

seismic events at Lucky Friday

Mine. Trans Inst Min and Metall

(Section A: Mining Industry). Vol.

106, pp. A148-A162.

PURPOSE: Identify geologic features that contribute to the

risk of rock bursts and link 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 reoccur

on a regular basis, countermeasures have been developed and

employed that reduce the level of risk. However, these countermeasures

must be appropriate to local geologic conditions and rock burst

mechanisms. 

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.
Spokane and Pittsburgh Research Laboratories

50 Office for Mine Safety and Health Research

Slope failure

SLOPE STABILITY HAZARD

RECOGNITION FOR METAL/NONMETAL

MINES 

RESEARCHERS: Jami M. Girard, Ed McHugh,

and Doug Scott

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Surface mining,

slope stability

BIBLIOGRAPHY

Girard J, Mayerle R, McHugh E

[1998]. Advances in remote sensing

techniques for monitoring rock falls

and slope failures. In: Peng SS, ed. 

Proceedings of the 17th International

Conference on Ground Control in

Mining. Morgantown, WV: West

Virginia University, pp. 326-331.

Sabine C, Denes L, Gottlieb M,

Kaminsky B, Metes P, Mayerle R,

Girard J [1999]. A portable spectropolarimetric imager: potential mine

safety and geologic applications. In:

Proceedings of the 13th International

Conference: Applied Geologic Remote Sensing (Vancouver, British

Columbia, Canada, March 1-3,

1999). ERIM International, Inc.,

Vol. I, pp. I-190 to I-194.

Tesarik DR, McKibbin RW [1999]. 

Material properties affecting the

stability of a 50-year-old rock

dump in an active mine. 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. 2000-110, RI

9651.

PURPOSE: Minimize hazards associated with unstable

mine slopes through an aggressive research approach involving engineering

controls, geotechnical design, advanced monitoring equipment, computer

models, and hydrogeologic investigations.

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 (MSHA) statistics from

1992 to 1998 revealed that 9% of the surface mine fatalities were directly

attributable to slope failures. Twenty workers were killed in slope-failurerelated accidents in the 5 years between 1994 and 1998. In 1999, at least

seven surface mine workers (or 15% of the surface mine fatalities as reported through October) have died in slope-failure-related accidents.

Open-pit mines are deeper than ever before, but the mechanics of rock

mass strength and rock mass movement at large scales is poorly understood. Four types of slopes may fail at open-pit mines: highwalls, dumps,

stockpiles, and tailings embankments. An understanding of slope failures

related to mining activity and the technology available to prevent these

types of failures is the focus of this project.

The project addresses three major areas. (1) 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 the proper use and placement of instruments and the limitations of various warning systems. (2) The efficiency and effectiveness of

current preventive measures are being evaluated, including physical supports (i.e., bolts, mesh, shotcrete, cable lacing, etc.), controlled blasting

methods, rockfall catchment systems, effects of unloading/unweighting,

buttresses, and dewatering techniques. (3) 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. 

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 applications, 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 51

Site of fatality caused by massive sandstone roof failure

in a mine in Mingo County, WV.

REDUCING INJURIES FROM THE FAILURE

OF COAL MINE ROOF SUPPORT SYSTEMS

RESEARCHERS: Dennis R. Dolinar, 

Gregory M. Molinda, and

Christopher Mark

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Roof bolts,

ground control, geology, support

system design, intersections, roof

falls

BIBLIOGRAPHY

Bauer ER, Pappas DM, Dolinar

DR, McCall FE, Babich DR

[1999]. Skin failure of roof and

rib in underground coal mines. 

In: Peng SS, Mark C, eds. Proceedings of the 18th International

Conference on Ground Control in

Mining. Morgantown, WV: West

Virginia University, pp. 108-114.

Chase FE, Mark C, Mucho TP,

Campbell PL [1999]. The advanceand-relieve mining method: a horizontal stress control technique. In:

Peng SS, Mark C, eds. Proceedings of the 18th International Conference on Ground Control in Mining. Morgantown, WV: West Virginia University, pp. 300-308.

Mark C [1999]. Application of

coal mine roof rating (CMRR) to

extended cuts. Min Eng 51(4):

52-56.

Mark C, Mucho TP, Dolinar D

[1998]. Horizontal stress and

longwall headgate ground control. Min Eng Jan:61-68.

PURPOSE: Develop methodologies and/or guidelines for the selection of

roof bolt support for coal mines. Better roof support design will lead to fewer

unplanned roof falls and reduce the number of associated injuries and fatalities.

RESEARCH SUMMARY: More than 100 million roof bolts are installed each

year in underground coal mines to prevent falls of ground. Nevertheless, during a

typical year, about 55% of operating mines will experience at least one roof fall. 

For example, in 1996, more than 2,600 roof falls were reported to the Mine Safety

and Health Administration, resulting in 711 injuries and 8 fatalities. Approximately

80% of these roof falls were caused by failure of the primary roof bolt support

system. The number of roof falls and fatalities indicates that the current methods

for designing support systems, based on trial and error and local experience, are

inadequate. There is a clear need for a scientific support selection methodology that

can be applied in a broad variety of geologic conditions.

The project’s approach is to use multivariate statistical techniques to

evaluate roof bolt performance and to determine the most important factors

affecting the stability of coal mine roof. A nationwide database has been

created through visits to 35 mines in Alabama, Colorado, Kentucky, Illinois,

Indiana, Ohio, Pennsylvania, Virginia, West Virginia, and Wyoming. Underground studies were conducted at each mine to characterize the roof geology

with the Coal Mine Roof Rating (CMRR), measure roof spans, and verify roof

bolt data. Extensive interviews were also conducted with mine staff to gather

details on roof fall history and roof bolt performance.

Preliminary statistical analyses indicate that there is a strong correlation

between the CMRR, the roof span, and the frequency of roof falls. Based on

the final results, new guidelines will be developed for the selection and design

of roof bolt systems. 

The new methodology will be presented to the mining community at Open

Industry Briefings (OIBs) on New Technology for Coal Mine Roof Support. The

OIBs will be held during the summer of 2000 in a variety of U.S. coalfields. The

OIB will also showcase a variety of roof support technologies that have been

developed or evaluated in recent years by the Pittsburgh and Spokane Research

Laboratories, including skin control techniques, intersection support, and horizontal

stress control techniques. 
Spokane and Pittsburgh Research Laboratories

52 Office for Mine Safety and Health Research

Truck depositing backfill in mine.

SAFE MONITORING OF ENGINEERED

BACKFILL

RESEARCHERS: Brad Seymour, Doug Tesarik, Dave

Denton, and Ted Williams

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Underground

mining, ground control, backfill

BIBLIOGRAPHY

Seymour B, Tesarik D, Larson M, Shoemaker J [1998]. 

Stability of backfilled crosspanel entries during longwall

mining. In: Peng SS, ed. Proceedings of the 17th International Conference on Ground

Control in Mining. Morgantown, WV: West Virginia University, pp. 11-20.

Tesarik D, Seymour B [1998]. 

Calibration of numeric models

using backfill and host rock

measurements. Presentation at

the Institute of Geonics, Academy of Sciences of the Czech

Republic (Ostrava-Poruba,

Czech Republic, July 14, 1998).

Williams T, Denton D [1998]. 

Cemented backfill reinforcement monitoring at the Lucky

Friday Mine. Report to industry, November 11, 1998.

PURPOSE: Develop practical methods and field techniques for

assessing the stability of underground backfill, innovative

instruments for monitoring mining-induced stresses and

displacements in backfill and host rock, and more accurate methods

of evaluating and forecasting the stability of cemented fill. 

RESEARCH SUMMARY: MSHA statistics show that ground

failure accounted for 44% of all fatalities in underground coal mines and

30% of the fatalities in underground metal/nonmetal mines over the past 10

years. Many of the traumatic injuries and fatalities resulting from these

ground control problems could be avoided through the use of backfill

mining techniques. Backfilling openings with an engineered fill material

provides excellent long-term ground support that improves the safety and

stability of underground workings. By reducing the number of abandoned

openings, backfilling also eliminates workings that pose dangers to mine

workers and diminish the efficiency of mine ventilation systems. 

Cooperative research will be conducted with several underground

mines currently using cemented backfill to address the lack of information

regarding the ground support characteristics of placed fill and the unknown

safety and health hazards associated with new backfilling applications. 

Practical field techniques will be investigated for assessing the competency

and in situ properties of placed cemented fill. 

Innovative rock and backfill instruments will be developed to provide a

better means of monitoring the behavior of placed fill and its interaction

with the host rock. These instruments will be installed to address safety

issues associated with unique backfilling applications and to demonstrate

the importance of using instruments and numerical modeling techniques to

monitor and evaluate the stability of underground openings.

By providing a more thorough understanding of backfill material

properties and mix designs, this research will lead to the development of

more competent and cost-effective backfill mixes and better quality control

measures for batching and placing fill. These advances will reduce the

safety and health hazards associated with backfilling operations, improve

the safety and stability of backfill mining methods, and provide a more

comprehensive engineering approach to the use of cemented fill.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 53

Installing a geophone in a borehole in the mine roof.

COAL BUMP REDUCTION THROUGH

ADVANCED MINE DESIGN

RESEARCHER: Keith A. Heasley

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Bumps, bounces,

coal mine, ground control, rock

mechanics

BIBLIOGRAPHY

Heasley KA, Chekan GJ [1998]. 

Practical stress modeling for mine

planning. In: Peng SS, ed. Proceedings of the 17th International

Conference on Ground Control in

Mining. Morgantown, WV: West

Virginia University, pp. 129-137.

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.

Mark C, Su D, Heasley KA [1998]. 

Recent developments in coal pillar

design in the United States. In:

Aziz NI, Indraratna B, eds. Proceedings of the International Conference on Geomechanics/Ground

Control in Mining and Underground Construction. Wollongong,

New South Wales, Australia: University of Wollongong, Vol. 2, pp.

309-324.

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 2 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). This system consists of 21 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, discreteelement, 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

54 Office for Mine Safety and Health Research

Fire suppression facility at Lake Lynn Laboratory.

FIRES, EXPLOSIONS, AND

VENTILATION

CONTROL AND SUPPRESSION OF MINE

FIRES

RESEARCHERS: Alex C. Smith and 

Charles P. Lazzara

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for

Occupational Safety and Health

1-800-35-NIOSH

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 will evaluate 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 mine and fire

suppression facility to compare the effectiveness of these systems to those

currently used in underground mines. The second task assesses the

flammability hazards of selected 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 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

Office for Mine Safety and Health Research 55

Failure of a mine ventilation stopping in the mine roof

simulator.

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

1-800-35-NIOSH

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, New South Wales,

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. 

RESEARCH SUMMARY: Nearly all underground mines in bedded

deposit formations use stoppings and seals (cement block walls) to control

ventilation. Failure of these structures can lead to disastrous mine

explosions and fires. The current Code of Federal Regulations (CFR)

requires underground coal mine stoppings to pass rigorous testing for

transverse loading capability. This criterion is for a freestanding wall. In

the mine, the ventilation structures are restrained on all four sides by the

mine roof, floor, and coal pillar ribs. The transverse loading capability is

significantly enhanced in this confined condition. 

Most mine ventilation stoppings are currently constructed from

concrete blocks weighing between 50 and 60 pounds per block. About

40% of the underground coal miners lift such blocks and could be at high

risk for musculoskeletal repetitive trauma disorders. Several emerging

materials that provide a 50% weight reduction in the building blocks for

mine ventilation stoppings have been developed. However, these

lightweight material constructions have failed to meet the transverse

loading requirements. A theoretical analysis indicates that they all would

have passed the transverse load requirements had they been tested in a

realistic restrained configuration.

Tests are being conducted in the unique mine roof simulator load

frame at the Pittsburgh Research Laboratory. These tests will more

accurately simulate the underground mine environment by confining the

stopping at the roof and floor interface and applying transverse loads to

determine the structural integrity of the walls. From these tests, more

realistic design criteria for ventilation structures are being developed. With 

these criteria, alternative constructions using various lightweight material

technologies will be examined as a means of reducing material handling

injuries.
Spokane and Pittsburgh Research Laboratories

56 Office for Mine Safety and Health Research

Construction of standard seal.

HYDROSTATIC EVALUATION OF MINE

SEALS

RESEARCHER: Michael J. Sapko

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mine seals,

explosion-resistant stoppings,

water inundation

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 hazards and

preventing the loss of lives. MSHA has a compelling need to evaluate

geometric scaling criteria for seals, alternative designs for highconvergence conditions, and seals for erection in 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 timeconsuming task, or were not evaluated at all because there was no practical

way to do it.

This research is aimed at developing pneumatic and hydrostatic

testing procedures to characterize new mine seal designs for explosion

resistance, atmosphere control, and water retention. It will help address

problems of concern to the United Mine Workers of America (UMWA),

MSHA, the mining industry, and seal manufacturers. Results will provide

information applicable to the on-site evaluation of new mine seals and on

the development of size scaling relationships and strength safety factors for

seals. Various seal manufacturers, MSHA, and the UMWA have shown

interest in partnerships for developing size scaling relationships and understanding failure mechanism associated with their seals under various conditions. The pneumatic and hydrostatic approaches would lend themselves

for use in evaluation of seals in operating mines.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 57

A NIOSH researcher prepares to inject sulfur

hexafluoride tracer gas into a gob gas venthole to

determine gas flow paths in the longwall gob.

CHARACTERIZATION AND MITIGATION OF

MINE GAS EMISSIONS

RESEARCHER: William P. Diamond

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

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.

Schatzel SJ, Diamond WP, Garcia

F, Mucho TP, LaScola JC, McCall

FE, et al. [1999]. An investigation

of longwall gob gas behavior and

control methods. In: Tien JC, ed. 

Proceedings of the Eighth U.S.

Mine Ventilation Symposium. 

Rolla, MO: University of MissouriRolla Press, pp. 43-51.

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 geologic characteristics, mining and ventilation practices, and

methane control systems vary considerably due to site-specific conditions

and the relative influence of each is unknown. The current focus of this

research is the increased methane emissions associated with the emerging

technology of mining increasingly larger dimension longwall panels in U.S.

coal mines. This project is investigating the factors controlling gas

emissions associated with longwall mining, in particular, gas emissions

from the gob, to develop and/or optimize control technologies to improve

safety in the underground workplace.

Due to the great 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. 

The field studies are currently being conducted in cooperation with a mine operating in the Pittsburgh Coalbed in southwestern Pennsylvania. These field

studies are being conducted in close coordination with organized labor (United

Mine Workers of America) and with State and Federal regulatory authorities

(Pennsylvania Bureau of Deep Mine Safety and Mine Safety and Health

Administration). Future field studies are expected to be conducted in the Western United States to determine the variability of results between mining regions. In addition to the methane control system improvements already developed from the preliminary results of the field studies, the tracer gas data are being used to develop a gob gas flow theoretical model. In addition to facilitating

an understanding of the intricacies of longwall gas flow, the theoretical modeling effort is being used to simulate and evaluate potential optimized methane

control strategies before they are proposed to the cooperating mine for field

testing.
Spokane and Pittsburgh Research Laboratories

58 Office for Mine Safety and Health Research

A nonelectric blasting cap.

EXPLOSIVES HAZARD SURVEILLANCE

AND EVALUATION FOR THE MINE

SAFETY AND HEALTH ADMINISTRATION

RESEARCHER: Thomas C. Ruhe 

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

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 conducting research on

other explosive hazards. 

RESEARCH SUMMARY: The three 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.

Currently, an investigation is being conducted on a detonator/booster

assembly that was involved in a recent fatal incident. Indications are 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 has been involved in two other incidents (one fatal) in recent years. 

The Pittsburgh Research Laboratory is drop-testing the explosive components in a borehole according to a test plan developed in cooperation with

MSHA to identify the most critical impact conditions. The results should

lead to the dissemination of appropriate warning information to explosives

users or suggest modified explosive handling procedures. Longer term

research will be conducted to determine the impact sensitivity of booster/

detonator assemblies to more precisely define the nature of these explosive

components.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 59

Experimental mine dust exposion.

EXPLOSION HAZARDS REDUCTION

RESEARCHERS: Kenneth L. Cashdollar and

Isaac A. Zlochower

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Explosions,

prevention, mining

BIBLIOGRAPHY

Cashdollar KL [1996]. Coal

dust explosibility. J Loss Prevention in the Process Indus

9(1):65-76.

Cashdollar KL, Zlochower IA,

Green GM, Thomas RA, Hertzberg M [1998]. Flammability

of methane, propane, and hydrogen gases. In: Proceedings of

the International Symposium on

Hazards, Prevention, and Mitigation of Industrial Explosions;

Colloquium on Gas, Vapor, Hybrid, and Fuel-Air Explosions. 

Schaumburg, IL: Safety Consulting Engineers, Inc., pp. 77-

101.

Sapko MJ, Weiss ES, Cashdollar KL, Zlochower IA

[1998]. Experimental mine and

laboratory dust explosion research at NIOSH. In: Proceedings of the International Symposium on Hazards, Prevention,

and Mitigation of Industrial Explosions; Eighth International

Colloquium on Dust Explosions. Schaumburg, IL: Safety

Consulting Engineers, Inc., 

pp. 120-142.

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 with multiple fatalities. Explosions

can be prevented or mitigated by minimizing methane concentrations through

ventilation, 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 provided to the Mining Safety

and Health Administration (MSHA) in the forensic investigation of explosions.

The current experimental research includes large-scale coal dust explosion studies conducted at the Lake Lynn Experimental Mine to study

coal dust particle size effects on limestone rock dust inerting requirements. 

This explosion research is also closely coordinated with the project on the

South African Stone Dust Barrier Evaluation at Lake Lynn. As part of

these mine tests, gas and dust samples are collected during and after the

explosions. These samples are analyzed in an attempt to better understand

the combustion mechanisms. The large-scale mine research is conducted in

conjunction with laboratory testing in PRL’s 20-liter explosibility chamber.

Research on frictional ignitions includes surveillance in commercial

mines and experimental studies. Surveillance of lightning-induced gob gas

explosions includes the evaluation of a pressure-balancing technique to reduce the volume of flammable methane within the gob at a mine in Alabama. 

Experimental research is being conducted on the relative incendivity of

sandstone, metal, etc., for igniting methane and hydrocarbon oils from mines. 

Close cooperation with the mining industry, the United Mine Workers of

America, and MSHA is expected. Industry briefings and direct technical

assistance are used to communicate the findings. Additional research on

frictional ignitions is being conducted in the 20-liter chamber by measurements of the hot-spot temperature and surface area necessary to ignite flammable gases, vapors from oil, and dust mixtures with air.
Spokane and Pittsburgh Research Laboratories

60 Office for Mine Safety and Health Research

Evaluating face airflow during

extended-cut mining.

EXTENDED-CUT AIR DELIVERY SYSTEMS

RESEARCHER: Charles D. Taylor

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

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 of

S Afr 52(2):48-52

Thimons ED, Taylor CD, Zimmer JA [1999]. Ventilating the

box cut of a two-pass 40-ft extended cut. In: Tien JC, ed. 

Proceedings of the Eighth U.S.

Mine Ventilation Symposium. 

Rolla, MO: University of

Missouri-Rolla Press, pp. 157-

165.

PURPOSE: Develop better ventilation techniques for delivering air to the

face and improved methane sampling strategies for estimating face

concentrations during extended-cut mining.

RESEARCH SUMMARY: More than one-half of all mechanized mining

units have variances to use extended-cut mining methods. Usually the

effective use of extended-cut mining methods requires that normal curtain

or tubing setback distances be increased. This makes efficient face

ventilation more difficult. Increasing the setback distance often reduces the

amount of intake air reaching the face, which can result in accumulations of 

methane. Worker safety is at risk if this methane is ignited by hot cutting

bits. Extended cutting should be employed only if it can be demonstrated

that methane levels can be maintained at safe levels.

This research is evaluating techniques that can be used to maintain

face airflow high enough to keep methane concentrations at safe levels

while employing extended-cut mining. During an underground mining

operation it is difficult to obtain data needed to determine the quantity of

air reaching the face. A full-scale ventilation gallery is used to simulate

ventilation conditions during extended-cut mining. Methane is released at

the face of the gallery, and concentrations of the gas are monitored at

multiple locations near the face. With this information airflow quantity and

distribution can be estimated. Face airflow quantities are estimated for

different machine locations, curtain and tubing setback distances, intake

and scrubber airflow quantities, and water spray configurations. Simulation tests are conducted for roof bolting and continuous mining operations.

During underground mining, face methane measurements are the primary means for determining if face ventilation is adequate. With extendedcut mining, it can be difficult to periodically obtain methane measurements

at the face. Gallery studies enable methane concentrations to be measured

at the face and multiple locations outby the face. Face and outby concentrations are compared to determine if reliable alternative methane sampling

strategies can be used to estimate face concentrations.

These gallery studies provide a quick and reliable method for evaluating extended-cut face ventilation systems and methane monitoring strategies in a controlled environment. Constantly changing conditions make

this impossible to do in an underground mine. However, the findings from

the gallery studies can be employed in mines to provide a higher level of

worker safety.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 61

Collecting SCSRs for 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

1-800-35-NIOSH

KEYWORDS: Self-contained

self-rescuer, respiratory protection, mine emergency escape.

BIBLIOGRAPHY

Kyriazi N [1999]. Performance

comparison of rescue breathing

apparatus. 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-

152, RI 9650.

Kyriazi N, Shubilla JP [1996]. 

Self-contained self-rescuer field

evaluation: fifth-phase results. 

Pittsburgh, PA: U.S. Department of Energy, RI 9635.

PURPOSE: Ensure that deployed self-contained self-rescuers

(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

in Morgantown, WV, and the Mine Safety and Health Administration

(MSHA).

The NIOSH Pittsburgh Research Laboratory (PRL) is conducting a

long-term evaluation of SCSRs deployed in underground coal mines. PRL

locates mine operators that are willing to participate in the study, trades

deployed SCSRs for new ones, and then tests the deployed SCSRs. 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 manufacturer’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.

Eighteen mines were visited in MSHA Districts 2, 4, 5, 9, and 11 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, an additional inspection criterion (a noise test) was added for one model of apparatus (approximately

40,000 in the field) by the manufacturer to detect apparatus with degraded

chemical canisters. In addition, another apparatus was found to have

leaked chemical from the canister to the breathing circuit, undetectable by

its inspection criteria. This unit (approximately 7,000 in the field) was recalled and decertified.
Spokane and Pittsburgh Research Laboratories

62 Office for Mine Safety and Health Research

Researchers vary laser powers to determine laser

ignition thresholds for a coal dust layer.

LASER SAFETY FOR HAZARDOUS

LOCATIONS

RESEARCHER: Thomas H. Dubaniewicz, Jr.

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Hazardous

locations, laser, methane

BIBLIOGRAPHY

Dubaniewicz TH Jr., Cashdollar KL, Gregory GM,

Chaiken RF [1998]. Ignition

of methane-air mixtures by

laser-heated small particles. 

In: Proceedings of the International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions;

Colloquium on Gas, Vapor,

Hybrid, and Fuel-Air Explosions. Schaumburg, IL: Safety Consulting Engineers, Inc.,

pp. 218-236.

Dubaniewicz TH Jr., Cashdollar KL, Monaghan WD

[1999]. Laser ignition of

flammable gas. In: Proceedings of the International

Laser Safety Conference. 

Orlando, FL: Laser Institute

of America, pp. 309-318.

Magison E [1998]. Ignition by

optical sources. In: Electrical

Instruments in Hazardous Locations. 4th ed. Durham, NC: 

Instrument Society of America, pp. 493-519.

PURPOSE: Develop recommendations for safe power and

power density limits for lasers used in underground coal

mines, specifically, in atmospheres containing flammable

methane-air and/or coal dust.

RESEARCH SUMMARY: Laser technology is being pursued as a way to

measure methane concentrations at the face of underground coal mines in

response to safety concerns with conventional measurement techniques. 

However, above certain power levels, lasers pose a risk of ignition of

flammable gas or coal dust.

Previous research demonstrated the explosion hazard of a new commercial fiber-optic powered instrument thought to be safe in explosive

atmospheres. Australian researchers reported that relatively modest levels

of laser power, when properly focused, may heat dust particles and cause

ignition of the surrounding methane air atmosphere. These developments

generated international interest in developing safety recommendations for

these emerging optical technologies.

Researchers are conducting ignition experiments to determine laser

power thresholds for igniting methane-air and/or coal dust. A theoretical

model of the ignition process has been derived. Correlation between theory

and experimental evidence would provide a solid justification for safety

recommendations. Maximum safe beam powers and power densities for

lasers will be recommended. Collaborators on the project include the International Society for Measurement and Control, the International Electrotechnical Commission, and the Laser Institute of America. This research is

expected to support regulatory and consensus standards formulation. 
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 63

Vertical exhaust trajectory from a fire

extinguisher is unaffected by the

underground mine ventilation air flow.

VENTILATION OF LARGE-OPENING MINES

RESEARCHER: William D. Mayercheck

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mine

ventilation, metal/nonmetal

mines, large openings

BIBLIOGRAPHY

Hartman HL [1997]. Mine

ventilation and air conditioning. 

3rd ed. John Wiley & Sons,

Inc.

Kohler JL, Thimons ED [1987]. 

An analysis of air volumeflowrate determinations for

mines. Min Sci and 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 producing commercial product

from in situ deposits such as limestone, salt, and gypsum. A wide range of

airborne substances within the mine air that may adversely affect miners’

health and safety include methane, diesel exhaust, radon, and blasting

byproducts. Many of these mines have large airways, with the largest

featuring cross-sectional areas that are over 60 times larger than typical

underground coal mines. Providing adequate quantities of fresh air into the

advancing face areas and long dead headings in these large room-and-pillar

operations is challenging. Adequate fresh air volumes are needed to dilute,

render harmless, and carry away toxic and explosive gases.

It is difficult and expensive to maintain adequate air velocities in these

large-opening mines. As air from the surface enters these underground openings, the air velocity is quickly diminished due to the increase in cross-sectional

entry area and the number of entries being ventilated. This air is often required

to travel great distances to reach the working areas. Because of the low air

velocities, the large entries and associated face areas are prone to air stagnation

and recirculation. Air flow in a cross-section of a large opening can actually be

moving in opposite directions at different elevations. The adverse health and

safety impacts of inadequate fresh air delivery in these mines are potentially

serious. Inspectors from the Mine Safety and Health Administration and the

Pennsylvania Bureau of Deep Mine Safety have expressed serious concerns

over this problem, as have many mine operators.

This new project will evaluate methods of increasing and monitoring

air flow in these large-opening mines. Because the use of traditional air

flow measurement techniques can be problematic in large-opening mines, a

primary goal of this project is to establish practical measurement techniques and methodologies for these mines. In addition to using traditional

tools, e.g., vane anemometers, smoke tubes, tracer gas, and pressure differentials, the application or adaptation of other relevant technologies will be

considered. Additionally, current face ventilation practices will be evaluated to determine if methods exist to increase air flow to the immediate

face. An important goal of the project is to publish a handbook of recommended practices for improving and monitoring the ventilation of largeopening underground mines.
Spokane and Pittsburgh Research Laboratories

64 Office for Mine Safety and Health Research

Flyrock being thrown by a surface blast.

INVESTIGATION OF FLYROCK INJURIES

AND FATALITIES

RESEARCHER: Timothy R. Rehak

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Blasting,

explosives, flyrock, mining

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. Blasting, although hazardous, is considered a very essential component of surface mining operations. Each blast is associated with fragmentation. In

many instances, the projection of rocks from the blast site (flyrock) extends

to a great distance.

Each year, rocks thrown beyond expected bounds result in fatalities or

serious injuries. Several of the reported incidents involved innocent

bystanders, some of whom were not even employed at the mine. Flyrock

and lack of blast area security are the major factors relating to blasting incidents 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.

In this new project, the approach is to critically review accident reports

from the Mine Safety and Health Administration and other Government agencies to determine those key factors that have contributed to “wild” flyrock

(i.e., flyrock thrown much farther than expected) and to determine why

persons are sometimes too close to a blast site. Selected blasting sites will be

visited and procedures examined to derive an in-depth understanding of paramount factors contributing to blasting incidents. Statistical analysis of parameters and causative factors of wild flyrock and blast area security accidents will be done. Through education/training and improving procedures

during blasting operations, it is anticipated that there will be a reduction in

the frequency of injuries from flyrock in blasting operations.

Partners/collaborators in the project are the Mine Safety and Health

Administration, Institute of Makers of Explosives (IME), and United Mine

Workers of America (UMWA).
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 65

Underground view of the multiple-entry section of the Lake

Lynn Experimental Mine.

LAKE LYNN LABORATORY

RESEARCHER: Eric S. Weiss

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

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 research conducted at Lake Lynn includes areas such as the development and evaluation of fire suppression systems and early warning technologies; development and evaluation of mine seals, stoppings, and bulkheads; 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 conducted at Lake Lynn is vital to agencies such as the Mine

Safety and Health Administration (MSHA) in the development of

regulations 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 Government

agencies, such as the U.S. Department of Transportation and the U.S.

Department of Defense, and other national and international research

organizations. Cooperative research with these agencies is conducted on a

resource availability, cost-reimbursement basis.

The unique ability of Lake Lynn to simulate virtually any underground

coal mine geometry provides a practical, realistic research laboratory to

study mine fires, explosions, respirable dust deposition, diesel fumes, noise

reduction, environmental remediation, etc., 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. Two recently completed underground chambers are now being used to evaluate the failure modes and

size-scaling relationships for mine seals and bulkheads. The surface facilities provide an isolated environment in which large-scale research and
Spokane and Pittsburgh Research Laboratories

66 Office for Mine Safety and Health Research

testing on diesel fuels, explosives, chemicals, and similar materials can be

conducted in a realistic, yet environmentally controlled manner. The availability of the large, open areas permits the setup of experimental facilities

to evaluate equipment and test novel concepts for the physical handling and

use of materials.

Technology transfer of Lake Lynn capabilities and research outcomes

are routinely conducted through open industry briefings, tours, and on-site

presentations and discussions with representatives from national and

international research agencies and governmental and private mining

organizations. Realistic mine rescue training evaluation programs are

conducted in the smoke-filled entries of the underground mine and at the

surface fire facilities with State and private teams from the West Virginia

Office of Miners’ Health, Safety, and Training; the Pennsylvania Bureau of

Deep Mine Safety; and a variety of mine operators. Research programs are

continuing to be conducted in cooperation with international mining

research organizations and industry, such as the Council of Scientific and

Industrial Research (CSIR) of the Republic of South Africa, Barclay

Mowlem Construction Limited of New South Wales, Australia, and Tecrete

Industries Pty. Ltd. of Queensland, Australia. Programs are ongoing with

several NIOSH researchers from Morgantown, WV. One study entails

collecting dust generated from cutting saw operations on various concrete

block and brick samples. Another program is using the mine’s single entry

as a low-velocity wind tunnel for an ergonomics study to determine the

accuracy of collecting respirable dust based on the location of the sampler

unit on a miner relative to the miner’s position to the air flow. West

Virginia University uses the surface and underground workings of Lake

Lynn as a field location for its mine surveying classes each year. 

The Lake Lynn project team members (1) support and coordinate Lake

Lynn research efforts for the Pittsburgh Research Laboratory research

groups, other NIOSH centers, MSHA, and other governmental and industrial organizations, and colleges and universities, (2) enhance the research

capabilities of Lake Lynn and establish plans to meet expected needs, and

(3) maintain safety, health, and environmental controls at Lake Lynn and

provide cost-effective maintenance at the laboratory for roads, grounds,

buildings, the Experimental Mine, surface test facilities, heavy equipment,

utilities, and computer facilities through close association with the Administrative Services Branch of the Pittsburgh Research Laboratory. 
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 67

Equipment at sand and gravel mine.

SURVEILLANCE

HAZARD REDUCTION IN SURFACE MINING

OF SAND AND GRAVEL 

RESEARCHER: C. M. K. Boldt

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining, sand

and gravel, economics

BIBLIOGRAPHY

Backer RR, Boldt CMK [1998]. 

NIOSH surface mine haulage

equipment research. Presentation at the 2nd Annual California OSHA Mine Safety and

Health Conference (Sacramento, CA, February 3-4, 1998).

Backer RR, Boldt CMK [1998]. 

Reducing haulage truck hazards

in surface mining. Presentation

at the CoalOps ‘98 Conference

(Lexington, KY, August 24-25,

1998).

Backer RR, Boldt CMK [1998]. 

Surface mine haul truck safety. 

Presentation at Open Industry

Briefing, 104th Northwest Mining Association Conference

(Spokane, WA, December 1,

1998).

PURPOSE: Collect information on the economic and social

costs of workplace injuries and fatalities at sand and gravel

operations using data from actual accident cases.

RESEARCH SUMMARY: According to the MSHA Metal-Nonmetal

Monitor of July 1, 1996, there were 34,379 employees working 59 million

hours in 6,162 sand and gravel mines in 1994. These mines had an average

of less than 6 employees each. The nonfatal days lost (NFDL) incident rate

was 4.05. Stone mills employed 66,196 workers at 703 operations. A cursory look at the MSHA accident data shows that sand and gravel operations

had 28 fatalities in 1995 and 34 fatalities in 1996. This is nearly one-third

of mining industry fatalities for each year.

At present, there is little or no good information on the true costs of a

mining injury or fatality. Costs involve more than just the direct costs to

the mining company or its insurer. Direct costs include such things as medical and insurance administration. Indirect costs, which include lost earnings, lost home production, lost fringe benefits, retraining and restaffing

expenses, and lost productivity caused by time delays, can often exceed

direct costs. This project will be directed to collecting information on direct costs and will involve the assistance of various collaborators. In addition, a protocol will be developed to measure indirect costs associated

with a worker injury or fatality.
Spokane and Pittsburgh Research Laboratories

68 Office for Mine Safety and Health Research

The total cost of all injuries was $393 billion in 1997. Workplace injuries accounted for almost one-third of those costs.

ECONOMIC COST MODEL FOR

TRAUMATIC INJURIES

RESEARCHER: H. Kenneth Sacks

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Economic

consequences, injuries, mining,

human capital

BIBLIOGRAPHY 

Haddix AC, Teutsch SM,

Shaffer PA, Dunet DO [1996]. 

Prevention effectiveness:

a guide to decision analysis and

economic evaluation. Oxford

University Press.

King EM, Smith JP [1988]. 

Computing economic loss in

cases of wrongful death. ISBN

0-8330-0888-9, pp. 34-46.

Leigh JP, Markowitz SB, Fahs

M, Shin C, Landrigan PJ

[1997]. Occupational injury

and illness in the United States:

estimates of costs, morbidity,

and mortality. Archives of Int

Med 157:1557-1568.

PURPOSE: Redesign the outdated Accident Cost

Indicator Model (ACIM) so that it can generate cost

estimates for mining injuries.

RESEARCH SUMMARY: The original model (referred

to as ACIM), which was developed by the former U.S. Bureau of Mines

(USBM), is a computer-based model that estimates the tangible costs of

work-related injuries and illnesses in the U.S. coal mining industry. It was

developed in the late 1970s to express the annual statistics of injury and

death in terms of costs (medical, worker’s compensation and union

benefits, lost production and wages, investigation costs, etc.) and to

allocate these costs to the characteristics of the work environments that

cause the accidents and to the sectors of society (public, private, and

family) that bear these costs. This model was used internally by the USBM

to generate estimated costs for mine accidents recorded in the Mine Safety

and Health Administration (MSHA) Accident/Injury/Illness Database. 

However, it was limited in its abilities, as it could compute costs only for

fatalities and permanent disabilities reported by coal mine operators. Less

severe incidents, incidents reported by metal/nonmetal operators, and

incidents reported by independent contractors were not covered. Further,

the model was purely theoretical and depended on numerous assumptions

about the demographics of the mining workforce. Today, the model is outof-date and no longer produces accurate estimates, even for coal operator

incidents.

The new model will use the same basic method used by other NIOSH

researchers, i.e., society costs based on the human capital approach. The

model will include medical and lost production—both market and

nonmarket components. Values will be based on actual costs of worker’s

compensation claims and on current wage and salary data for the mining

industry.

The model will compute costs for all incidents that result in injury and

will generate output in a common, PC-based database format (such as

MSAccess and SPSS for Windows).
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 69

Testing GIS as a surveillance tool.

IMPROVING SURVEILLANCE DATA UTILIZATION

THROUGH GEOGRAPHICAL INFORMATION SYSTEMS

RESEARCHER: Nathan T. Lowe

AFFILIATION: Spokane Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining,

surveillance, geographical

information systems

PURPOSE: Develop and demonstrate geographical information system

(GIS) methodologies for spatially mapping and analyzing accident and

occupational disease information.

RESEARCH SUMMARY: This research will begin by producing basic

GIS maps that show locations associated with selected mining health and

injury information by topic (accident classification by State or commodity,

for example). Combinations of those mapping and analytical techniques

that offer the greatest potential for discovering regional differences in the

occurrence of accidents and health risks will be determined. 

Utilizing recently available GIS technology, the project will then explore the usefulness of producing and publishing interactive maps on the

Intranet/Internet. Such maps could allow users to perform specialized

queries by selecting different combinations of themes from available

options. Other GIS products will be investigated, such as linking GIS and

Document Management System technology that would allow users to access health and safety data simply by clicking on specific features of a map

of the U.S. mining industry. 

These technologies will allow surveillance data to be examined in relation to geographic locations associated with accidents or exposure sites. 

This information will enhance our surveillance efforts by allowing spatial

analyses that are likely to reveal causal relationships between injury variables not heretofore seen or realized. A secondary objective is to demonstrate and use GIS technology to disseminate mining industry disease and

injury data through the Intranet and Internet.
Spokane and Pittsburgh Research Laboratories

70 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 Landen

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Cardiovascular

disease, stress, coal mine dust

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 appear to have an

elevated risk of death from heart attacks (myocardial infarction) (MI). 

Factors involved in the risk of atherosclerotic heart disease include genetics

and lifestyle factors, 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.

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 will determine 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 will 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 will be examined.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 71

Injuries to face workers are being analyzed to determine areas

for research.

ANALYSIS OF RISK TO FACE WORKERS

IN CONTINUOUS COAL MINING

RESEARCHER: William H. Lewis

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Mining, mine

face workers, injuries, analysis

BIBLIOGRAPHY

Glowacki AF [1996]. PC-based

software for analyzing U.S.

mining accidents, injuries, and

illnesses. 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. 92-99.

PURPOSE: Perform an in-depth injury/risk analysis of

face workers in underground coal mine continuous mining sections.

RESEARCH SUMMARY: Approximately 50,000 miners work in U.S.

underground coal mines. About 16,000 of these miners operate equipment

full-time at the mine face, where they are exposed to a wide range of safety

and health hazards. Another 17,000 miners routinely enter the face area

during their shift for supervisory, maintenance, and other activities. From

1993 to1997, U.S. coal mine operators reported 44,376 underground accidents, 114 fatalities, 333 disabling injuries, and 952,275 lost workdays.

 

Many hazards at the coal mine working face greatly increase the safety

and health risks to equipment operators and other support personnel in this

area. Emerging equipment control technologies offer potential for reducing

accidents and injuries at the face area.

Presently, accident data from the Mine Safety and Health Administration (MSHA) are categorized by type of incident rather than causes of the

incident. This study will review MSHA accident data and narratives and

will attempt to classify accidents by root causes. At the same time, a detailed analysis is being performed to determine which hazardous tasks need

further study and research.

The combination of these two approaches will lead to a greater insight

into the accident/injury picture and the formulation of future areas of research for reduction of accidents and injuries. The specific overall objectives of this project are to (1) provide an in-depth overview of the incident and injury data in underground coal mine face areas, (2) assess the

impact of emerging technologies involving the control of mining equipment

on the accidents and injuries, (3) make recommendations for future areas of

research to reduce injuries at the face area, and (4) prepare a model surveillance report and database for injuries at underground continuous coal

mine face areas.
Spokane and Pittsburgh Research Laboratories

72 Office for Mine Safety and Health Research

Installation of novel roof support system

with hydraulically powered lifting device.

EMERGING TECHNOLOGIES

EMERGING TECHNOLOGIES AND OTHER ISSUES IN

MINING

RESEARCHER: George R. Bockosh

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Emerging

technology, mining

BIBLIOGRAPHY

Rand Corp. [1998]. New forces

at work: industry views critical

technologies. Rand Corp.,

Santa Monica, CA.

PURPOSE: Identify anticipated major changes that are expected to

impact the safety and health of mine workers in the next 5 years.

RESEARCH SUMMARY: The mining industry has made significant

gains in safety, health, productivity, production, and environmental

impact. In achieving these impressive accomplishments, it has adopted

new technologies, accommodated encroachment of a world market, and

addressed new environmental regulations. It has also increased production

in response to continued growth in consumption of many commodities. 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. This will enable NIOSH’s mine safety and health research

program to take advantage of changes that could improve miner’s safety

and health and prepare interventions to neutralize emerging threats. The

study of emerging technologies is also a National Occupational Research

Agenda (NORA) priority area.

This new project is identifying anticipated major changes that are

expected to impact the safety and health of mine workers in the next 5

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 certain commodity can influence miner safety and

health. For example, the recent passage of the Transportation Equity Act

for the 21st Century (TEA-21) has resulted in a sharp increase in the

consumption and mining of crushed stone. This has caused new quarries to

open and existing quarries to work longer hours. Potential safety and

health concerns include the impact of extended shifts, consecutive days

worked, and an influx of new and inexperienced workers. A sudden increase in production in any commodity is also expected to increase the

likelihood that new equipment and processes will be developed and

implemented. Therefore, identification of commodities that are expected to

experience substantial increases in demand will identify those mining
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 73

industry segments most likely to embrace new technology.

Social pressures and public policy also impact mining. For example,

the Clean Air Act has resulted in a shift in coal production to low-sulfur

seams, causing mines in the Midwest to close and production in the western

and southern Appalachian regions to increase. This shift has caused an increase in surface mining and a change in underground mining conditions. 

Stone mines need to be located near their markets, but few towns want

them nearby because of the dust, noise, and environmental and safety issues. Public opinion is causing these mines to move underground, which is

a potentially more hazardous mining location.

Demographic trends are also impacting mining. Scarce hiring during

the last 2 decades has resulted in the average age of a miner to be 50 years

in some segments of the mining industry. Finally, legislative action such

as TEA-21, the Clean Air Act, and anticipated mountaintop mining legislation in West Virginia will impact who is mining and where mining will

take place.

Since 1991, the U.S. Congress has sponsored reports about the status of

critical technologies in the United States. The latest such effort, New

Forces at Work by the Rand Corp., describes a methodology that will serve

as a model for an effort to determine those technologies in mining that are

critical to its continued performance. For example, rock cutting methods

might be one such critical technology. It is expected that limiting factors

will be the subject of continued research and, as such, will be the areas

where new technology is likely to emerge. Once these critical technologies

are defined, patent and literature searches, along with interviews and

possibly focus group meetings, will be completed to determine likely

candidate advancements.

Finally, by combining the results of the analysis described above, new

technology and likely trends that are expected to impact miner safety and

health will be identified, along with recommendations for targeted etiological and intervention research efforts.
Spokane and Pittsburgh Research Laboratories

74 Office for Mine Safety and Health Research

The safety of programmable electronics requires a

system-atic, integrated approach for the software,

hardware, and people.

SYSTEM SAFETY: PROCESSOR CONTROL

APPLICATIONS

RESEARCHER: Thomas J. Fisher

AFFILIATION: Pittsburgh Research Laboratory 

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: Emerging

technology, control technology,

mining

BIBLIOGRAPHY

Lutz RR [1992]. Analyzing

software requirements errors

and safety critical, embedded

systems. In: Proceedings of the

Software Requirements Conference, pp. 99-106.

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.

PURPOSE: Develop a series of recommendation

documents detailing safety processes for programmable

electronic-based mining systems.

RESEARCH SUMMARY: This research addresses the emerging technology of programmable electronics, including microprocessors, personal

computers, programmable logic controllers, and the associated software, in

mining. Programmable electronics brings new hazards due to added complexities and the ambiguous nature of software. The Mine Safety and

Health Administration (MSHA) addresses only the permissibility of equipment. Thus, equipment can be permissible but not safe to operate, as evidenced by accidents involving programmable electronics.

The trend is for increasing use of programmable electronics in diverse

applications that include longwall systems, atmospheric monitoring systems, mine hoists, and mine load-haul-dump vehicles. MSHA has recognized the need to address the safety of programmable electronics before it

proliferates in mining. The mining industry’s experience with safely applying the technology is small, and no guidelines or standards exist for its

safe use in mining.

 

Other industries (military, rail transportation, medical devices, and

aviation) have been confronted with the safety challenges and needs of

programmable electronics. They employ system/software safety standards

and guidelines. The process encompasses hardware, software, humans, and

the operating environment for the equipment's life cycle.

Researchers are using the same approach that other industries have 

taken to focus on a risk-based, system safety process for programmable

electronics in mining. Functional safety processes are being developed for

design, testing, approval/certification, operation, and maintenance of

mining systems employing programmable electronics. The project’s

recommended safety processes will benefit the U.S. mining industry and

the global mining community. MSHA is a partner on this project, and

several mine equipment manufacturers and mine operators are cooperators.
Spokane and Pittsburgh Research Laboratories

Office for Mine Safety and Health Research 75

A researcher collects information at an

underground mine site.

OUTCOME MEASURES FOR MINING SAFETY AND

HEALTH RESEARCH

RESEARCHER: Kenneth L. Williams

AFFILIATION: Pittsburgh Research Laboratory

National Institute for 

Occupational Safety and Health

1-800-35-NIOSH

KEYWORDS: GPRA, mining, performance measures

PURPOSE: Identify the type of performance measures appropriate for

research conducted by NIOSH’s Office for Mine Safety and Health Research (OMSHR).

RESEARCH SUMMARY: The Government Performance and Results Act

(GPRA) requires Federal agencies to establish standards measuring

performance and effectiveness. The law requires the development of

strategic plans describing overall goals and objectives, annual performance

plans containing quantifiable measures of progress, and performance

reports describing success in meeting those standards and measures.

Measuring the impact of research is particularly challenging for several

reasons. First, by its very nature, the results of research are often uncertain. 

A negative result (e.g., the discovery that a particular process will not work in

certain applications) should not be viewed as a failure, but rather an important contribution to the body of scientific knowledge. 

Secondly, for a variety of reasons, the results of successful research are

often not adopted until years after the discovery or development of a process or

product. For example, a product that is too expensive today may become acceptable after manufacturing processes or the discovery of substitute materials

make the product affordable. An impact assessment process that ends with the

research project will most often not reflect the eventual benefit of the research. 

Finally, NIOSH is usually not the only party that can influence the solution of

the problem. Any performance measurement must assess the success of that

portion of the solution process that NIOSH can influence.

This new project begins by examining the detailed requirements of the

GPRA and the performance measures used by other Government research

agencies. Those measures are being examined to see if they can be tailored

to our research situation. Various congressional supporters and architects

of the GPRA have offered commentary and ratings of the performance

plans of various research agencies. Those comments are being examined as

guidance for what type of measures meet their expectations. Finally, the

history of successful research projects or programs is being studied to learn

about appropriate performance measures.
Delivering on the Nation’s Promise:

Safety and health at work for all people 

Through research and prevention

For information about occupational safety and health topics contact NIOSH at:

DHHS (NIOSH) Publication No. 2000-109

1-800-35-NIOSH (1-800-356-4674)

Fax: 513-533-8573 

E-mail: pubstaft@cdc.gov

www.cdc.gov/niosh