Possible Impact of New Safety Technology Developments on the 

Future of the United States Mining Industry 

R G Gurtunca 1 

1. Director, Pittsburgh Research Laboratory, National Institute for 

Occupational Safety and Health (NIOSH), PO Box 18070, Pittsburgh 

PA 15236, USA. Email: cei4@cdc.gov 	

ABSTRACT 

The future of the United States (US) mining industry will be affected 

greatly by recent coal mining disasters. These have resulted in new 

legislation which will have an impact on mining economic costs as well 

safety and health of miners. This paper discusses the changes that new 

legislation and regulations are making to the industry and current 

research that is producing technologies to make mining safer and will 

likely impact the future of mining. 

INTRODUCTION 

American coal production in 2007 was 1147 million short tons. 

Most of this coal is consumed domestically, with annual exports 

of coal about 50 million tonnes. One third of annual production 

is produced at surface mines and the rest from underground 

mines. This coal is produced by about 82 000 miners working at 

1400 coal mines. 

Major improvements in coal mine safety have been made in the 

US since the Federal Mine Safety and Health Act of 1977. The 

fatal injury rate in . underground coal mines between 1977 and 

2004 was reduced by 47.8 per cent to 0.036. The annual number 

of fatalities dropped from 112 to 14 during that period. Likewise, 

the non-fatal days-lost injury rate was reduced by 42.6 per cent 

from 10.87 to 6.24. However, during the past three years a number 

of coal mining disasters have occurred that have had major impact 

on mining in the United States. 

The recent major mine incidents began in 2006 with an 

explosion on January 2 at the Sago mine in West Virginia which 

killed 12 miners. A fire at the Aracoma Alma No 1 Mine in West 

Virginia on January 19 caused two fatalities. On 20 May 2006, 

there was an explosion at the Darby No 1 mine in Kentucky which 

resulted in five more deaths. On 6 August 2007, six miners were 

killed by a coal outburst when pillars failed and violently ejected 

coal over a large area. Ten days later, two mine employees and a 

federal mine inspector were killed in a coal outburst during rescue 

efforts. The number of fatalities in US coal mines in 2004 was 28 

and dropped to 23 in 2005. Primarily as a result of the above 

disasters, the fatalities increased to 47 in 2006 and 47 in 2007. 

MINER ACT 

These major mine accidents caused great public concern and led 

the US Congress to pass the Mine Improvement and New 

Emergency Response Act of 2006 (MINER Act) on 24 May 

2006. The coal mining disasters and the MINER Act have had 

very significant effects on the coal mining industry in the US. 

Some of the major provisions of the MINER Act include: 

• 	 required wireless two-way communications and an electronic 

tracking system within three years, permitting those on the 

surface to locate persons trapped underground; 

• 	 required each mine to have available two experienced rescue 

teams capable of a one hour response time; 

• 	 required new safety standards relating to the sealing of 

abandoned areas in underground coal mines, increasing the 

requirements for strength of the seals; 

• 	 established a competitive grant program for new mine safety 

technology to be administered by National Institute for 

Occupational Safety and Health (NIOSH); 

• 	 established a technical study panel for belt air to investigate 

the use of air from conveyer belt mine entries to ventilate the 

mine face; and 

• 	 established a permanent Office of Mine Safety and Health in 

NIOSH, which helps ensure a viable and long-term focus on 

mining safety and health. 

The Mine Safety and Health Administration (MSHA) has 

responsibility in the US for promulgation and enforcement of 

Federal mine safety regulations. The MINER Act required 

MSHA to act on new regulations and set up deadlines by which 

some of the new regulations were to be finalised. 

NIOSH MINING RESEARCH PROJECTS 


RELATED TO MINER ACT 


NIOSH does research to improve occupational safety and health 

for all workers including miners. NIOSH assumed the sole Federal 

responsibility for research on mine safety after the closure of the 

US Bureau of Mines in 1996. They inherited from the Bureau of 

Mines the mining research laboratories in Pittsburgh, PA and 

Spokane, WA. The NIOSH mining program currently has about 

245 employees and a budget for 2008 of $39 million. 

The current NIOSH mining program is aimed toward seven 

major strategic goals. These are: 

1. 	 reduce respiratory diseases in miners associated with coal 

worker pneumoconiosis, silicosis, and diesel emissions; 

2. 	 reduce noise-induced hearing loss (NIHL); 

3. 	 reduce repetitive/cumulative musculoskeletal injuries; 

4. 	 reduce traumatic injuries; 

5. 	 reduce the risk of mine disasters (fires, explosions, and 

inundations) and enhance the safety and effectiveness of, 

emergency responders; 

6. 	 reduce ground failure fatalities and injuries; and 

7. 	 determine the impact of changing mining conditions, new 

and emerging technologies, training, and the changing 

patterns of work. 

The intramural research done by NIOSH related to prevention 

and response to mine fires and explosions is directed toward 

strategic goal number five. This research is done primarily at the 

NIOSH Pittsburgh Research Laboratory (PRL). The NIOSH 

strategy in this area is in order of priority: prevention, escape, 

and rescue. Our research is designed first at preventing 

explosions or fires that could endanger the lives of miners, 

second at technology to allow miners to escape if a serious 

incident occurs and third at technology that would facilitate the 

r~scue of miners who might be trapped underground. 

Many of the research projects at PRL have direct relevance to 

preventing fatalities from the types of mining accidents that 

occurred in 2006 and 2007. Some of these projects will be 

described next, as well as a few other projects that are likely to 

have significant impact on American mining in the future. 
Mine explosion prevention 

Research is being done on explosion propagation and explosion 

combustion mechanisms through full-scale tests at the Lake Lynn 

Experimental Mine (LLEM) and laboratory tests. The LLEM 

research includes flame propagation in large volumes of nonuniformly mixed methane, the effects of non-uniform zones of 

coal and rock dust along an entry and the effects of coal dust on 

the ribs/roof compared to floor dust. Researchers also study the 

amount of rock dust necessary to inert typical mine size dust for 

both high and low volatile coals. Basic research on explosion 

mechanisms and flame propagation attempts to reach a more 

fundamental understanding of mine explosions. NIOSH and 

MSHA conducted joint research to evaluate explosion blast 

effects on mine ventilation stoppings at the LLEM. After mine 

explosion accidents MSHA conducts investigations to determine 

the causes as a means to mitigate or eliminate future occurrences. 

As part of these post-explosion investigations the condition of 

underground stoppings, including the debris from damaged 

stoppings, is documented as evidence of the strength and 

direction of explosion forces (see Figure 1). These results assist 

investigators in determining the explosion forces that destroy or 

damage stoppings during actual coal mine explosions (Weiss 

et al, 2006) 

FIG 1 - Ventilation stopping partially destroyed by 

explosion pressure. 

Coal dust explosibility meter 

The coal dust explosibility meter (CDEM), shown in Figure 2, is 

the first device to provide an immediate capability for 

determining if coal dust concentrations in active areas of 

underground coal mines have been sufficiently mixed with rock 

dust to prevent risk of explosion. This meter will quickly 

determine the explosibility and the incombustible content of coal 

and rock dust mixtures in coal mines, thereby improving sample 

analysis and rock dusting practices. The CDEM measures the 

explosibility of a coal and rock dust mixture by an optical 

reflectance method. Since rock dust is white and coal dust is 

black, the intensity of reflected light depends on the 

concentration of rock dust in the mixture. The CDEM, when 

calibrated with actual mine dust mixtures, can be used to 

determine the approximate percentage of rock dust in the coal 

and rock dust mixture. PRL developed the theory and technology 

behind the device and a prototype was developed in collaboration 

with the Geneva College Centre for Technology Development. 

NIOSH and partners received the prestigious R&D 100 Award 

for the PRL-developed meter. 

In a recent study, NIOSH personnel accompanied MSHA 

inspectors on their routine surveys in underground coal mines. 

While underground, NIOSH personnel and MSHA inspectors 

F

used the CDEM to assess the explosibilities of the dust samples. 

The values of per cent incombustible content (per cent IC) 

determined by the CDEM correlated with those later obtained by 

low temperature ashing (LTA) in both MSHA and NIOSH 

laboratories. Further, the meter identified some samples as 

potentially explosible that LTA analysis had found to possess 

sufficient rock dust for inerting. The CDEM provides more 

information on the hazards in the mine. Rapid identification of 

areas with explosible dust mixtures using the CDEM allows for 

immediate intervention rather than a wait of several weeks for 

laboratory analysis (Harris et al, 2008). 

IG 2 - Coal dust explosibility meter (CDEM). 

Fine coal dust 

There are several explosion hazard scenarios that are not 

sufficiently understood and that are believed to have been 

contributing factors to recent mine explosions. Of specific interest 

is the combustion of large volumes of non-uniformly mixed 

methane, which may present a different risk than the typical face 

ignition. Another important question is whether the 65 per cent 

rock dusting requirement for mine intakes is still sufficient to inert 

the coal dust, since the regulation was based on the average size of 

coal dust found in mine intakes during the 1920s. Recent analyses 

of mine dust samples have shown that the coal dust in many mine 

intakes is significantly finer in size than the regulations assume. 

The size of the coal dust is relevant to the amount of rock dust 

required to inert the coal dust, with more rock dust needed to inert 

finer sizes of coal dust. Dust samples were collected by MSHA 

inspectors from underground coal mines throughout the US. 

Samples were normally collected in several intakes at each mine. 

The laboratory analysis procedures included acid leaching of the 

sample to remove the limestone rock dust, sonic sieving to 

determine the dust size, and low temperature ashing of the sieved 

fractions to correct for any remaining incombustible matter. The 

results indicate that particle sizes of mine coal dust in intake 

airways are finer than those measured in the 1920s (Sapko, 

Cashdollar and Green, 2006). 

Improving methane control practices in coal mines 

The goal of the methane control research is to identify and model 

methane emissions in coal mines to improve the effectiveness of 

methane control technology and reduce the explosion hazard for 

underground miners. Although longwall mining productivity can 

far exceed that, of room-and-pillar mining, the total methane 

emissions per extracted volume associated with longwall sections 

are generally higher than those for continuous miner or pillar 

removal sections. Increased face advance rates, increased 

productivities, increased panel sizes and more extensive gate road 

developments have challenged existing designs for controlling 
methane on longwalls. NIOSH examined a number of practices 

designed to maintain concentrations in mine air within statutory 

limits and consistently below the lower explosive limit. In a recent 

report, several practical guidelines are recommended for 

controlling longwall coalbed methane. All predictions are based 

on determinations made for the Pittsburgh coalbed in southwestern 

Pennsylvania (Schatzel et ai, 2008). 

Improving underground coal mine sealing 

strategies 

Since 1986, 12 known explosions have occurred within the 

sealed areas of active US underground coal mines. Most of these 

explosions destroyed the seals that are structures built to isolate 

abandoned mining panels or groups of panels from the active 

workings. Recent explosions in the US underground coal mining 

industry suggest that previously accepted seal construction and 

design methodologies are inadequate. The new MSHA 

emergency temporary standard for 'sealing of abandoned areas' 

has raised the explosion pressure design criteria for seals from 

the old standard of 20 psi to 50 psi or 120 psi, depending on 

whether or not the mining company chooses to monitor and 

maintain the sealed area atmosphere inert. This new standard is 

based in part on the recently published NIOSH report 'Explosion 

pressure design criteria for new seals in US coal mines' (Zipf, 

Sapko and Brune, 2007) which developed the scientific basis for 

these new seal standards based on the explosion pressures that 

could develop. The mining community needs engineering 

guidelines immediately to better meet the new MSHA regulatory 

requirements for sealing abandoned areas of coal mines. NIOSH 

initiated a new seals research project which seeks to eliminate 

disasters from gas explosions within sealed areas of coal mines 

through improved engineering of the complete sealing process 

and better education of the mining workforce. Attaining this 

outcome requires research efforts to: 

• 	 develop fundamental scientific understanding of explosive 

mixture accumulation and explosion pressures developed by 

gas and dust explosions within sealed areas of coal mines; 

• 	 develop engineering procedures for sealing abandoned areas 

of coal mines, including structural design of seals and 

ventilation planning before and after sealing; 

• 	 develop management systems to control methane 

accumulation within sealed areas, including monitoring 

procedures and self- and artificial-inertisation methods; and 

• 	 conduct technology transfer to educate the mining 

community about the potential dangers posed by sealed areas 

and measures to eliminate it. 

NIOSH also is collaborating with researchers from US Army 

Corps of Engineers and Naval Research Laboratory on simulations 

and studies to increase understanding of methane explosions. 

Mine escape and rescue 

A systematic miner escape and safe rescue strategy is necessary 

when mine accidents such as fires or explosions occur and lives 

are in danger. NIOSH is investigating how to help miners be 

capable of timely self-rescue under adverse conditions, first 

responders and mine rescue teams be capable of rapid, state-ofthe-art safe rescue and management organisations that can 

effectively support these goals (Figure 3). 

A NIOSH numbered publication Guidelines for Escape and 

Rescue in Underground Coal Mines is being prepared that will 

include the research findings, key issues and recommend 

successful practices in escape and rescue for the US. Researchers 

have obtained information on escape and rescue practices in 

several of the major international coal mining areas including 

Australia, South Africa, UkraineIRussiaIPoland and China. Key 

issues and successful practices in escape and rescue were 

identified from a review of literature and in collaboration with 

stakeholders in the US during regional workshops and 

interviews. These practices are being analysed to determine key 

strategic aspects of mine escape and response applicable to the 

United States coal mining industry. The guidelines summarise 

strategies for safe and systematic response to underground coal 

mine fire and explosion incidents. 

FIG 3 - Mine rescue team in training. 

Refuge chambers 

Refuge chambers are one option for safety protection in the event 

of explosions or fires. In the United States, the use of refuge 

chambers in coal mines has generated debate. While refuge 

chambers can save lives, it is also argued that they may cause 

miners to seek refuge rather than attempt to escape their 

hazardous situation. There are a number of considerations 

involved with this approach, including the capabilities of 

stations, the type and location of structures, design criteria, and 

maintenance and training issues. Section 13 of the MlNER Act 

required NIOSH to conduct: 

... research, including field tests, concerning the 

utility, practicality, survivability, and cost of 

various refuge alternatives in an underground 

coal mine environment, including commercially 

available portable refuge chambers. 

The NIOSH report on this work summarises the findings of 

such research, focusing on specific information that could inform 

the regulatory process on refuge alternatives (NIOSH, 2007). 

Further, gaps in knowledge and technology that should be 

addressed to help realise the full potential of refuge alternatives 
were also identified. The report concluded that the refuge 

alternatives have the potential for saving lives of miners if part of 

a comprehensive escape and rescue plan, and if appropriate 

training is provided. Two viable refuge alternatives are in-place 

shelters and portable chambers that are inflatable or rigid. 

In-place shelters provide superior refuge environment and may 

possibly be connected to the surface by borehole. However, it 

would not be possible to keep them within 1000 - 2000 feet of 

the face and extended distances would have to be allowed for 

them to be used. NIOSH testing found operational deficiencies in 

some commercially available portable chambers that could delay 

their deployment in mines. Testing and certification of both 

refuge chambers and in-place shelters would be needed. While 

additional development is needed, the benefits of these refuge 

alternatives merit their deployment in underground coal mines. 

The 2006 MINER Act directed MSHA to consider rule making 

on refuge chambers. However, Congress subsequently mandated 

action in language included in the 2008 appropriations bill. MSHA 

has proposed a regulation for three types of acceptable refuge 

alternatives: prefabricated self-contained units, a secure space that 

is constructed in place, or materials prepositioned for miners to 

use to construct a secure space. The Agency has until the end of 

2008 to issue a final rule. PRL has also begun a new project that 

will result in training materials and guidelines to help ensure that 

miners receive adequate training on this important topic. 

Emergency communication and tracking 

Mine tragedies over the past few years have underscored the 

need for reliable two-way communications between underground 

miners and rescuers located on the surface. Presently no system 

has demonstrated even the most basic requirements for 

emergency communications. However, there is considerable 

optimism that one or more two-way voice communication 

system prototypes could be further developed and brought to a 

commercialisation phase within a few years. Towards that end, 

and to fulfill the requirements of the MINER Act of 2006, 

NIOSH is sponsoring several research contract initiatives to 

develop and demonstrate two-way communications systems. 

To address the requirements of the MINER Act in a timely and 

cost-effective manner, the primary activity has been the awarding 

of competitive contracts to develop and test several promising 

communications and tracking technologies. Three of the most 

promising communication systems are briefly described in 

the paper. 

Survivable leaky feeder mine communication 

system 

Under the Emergency Supplemental Appropriations that 

accompanied the MINER Act of 2006, a contract was awarded to 

Pillar Innovations to design, develop and demonstrate a 

survivable wireless leaky feeder communications distribution 

system capable of maintaining mine wide operational integrity 

after an emergency situation such as a mine fire, roof fall or 

explosion. Survivability consists of two principle aspects, 

hardening and redundancy. Hardening involves measures taken 

to improve the ability of the system to continue to perform after 

mine incidents and includes hardening of the cable and other 

components that are part of the communication system. 

Redundancy allows the system as a whole to remain operational 

even if a section of cable is damaged by an event. 

An extensive in-mine test program was completed involving 

both hardening and redundancy techniques. Based on the results 

of these tests, a system design was developed that takes 

advantage of the best approaches for hardening and redundancy 

in providing a survivable leaky feeder system. The design uses 

a multiple base station loop-around approach, where if the 

leaky feeder cable breaks, the system reverses transmissions of 

communications to allow communications with the surface from 

both sides of the break. Base stations on the surface at different 

mine shaft locations are connected via a surface fiber optic link 

to allow the reversing (Figure 4). The design also uses antennas 

and low-cost cables to provide communication coverage in 

additional mine passageways and other mine locations where 

miners may work and independent redundant trunks in by the last 

opening to the surface. 

Leaky Feeder Using Redundant Loop 

Primary Base 


Station 
 Secondary Base 

Station 

Fibre Optic Link 

Portal Shaft Mine Shaft 2 1 

Leaky Feeder Cable 

FIG 4 - Survivable leaky feeder mine communication system. 

The system design described above has been implemented at 

Consol Energy Loveridge mine, a large, complex underground 

coal mine, for long-term system test and evaluation. 

This system represents one important building block that 

mines can use to comply with the MINER Act, and importantly, 

this system can be upgraded in the future to take advantage of 

newer technologies for improved functionality. 

Wireless mesh communication and tracking 

system 

NIOSH has contracted with L3 Communications to develop a 

wireless mesh communication and tracking system, and to deploy 

the system in a cooperating mine in West Virginia. The NIOSH 

contract includes development of a new digital radio handset. The 

L3 wireless mesh network is a communications network made up 

of radio nodes that routes radio signals from the miner's handset to 

the intended destination, either on the surface or to other handsets 

within the mine. The node locations are fixed and known to the 

network, allowing miner handset locating features to be easily 

integrated into the system (Figure 5). 

A mesh network is reliable and offers redundancy. When one 

node can no longer operate, the rest of the nodes can still 

communicate with each other, directly or through one or more 

intermediate nodes. The L3 system is designed to operate with an 

existing leaky feeder system installed in this mine, adding even 

more redundancy to the system. A handset can act as a repeater 

for another handset that may not be within range of a node. 

Backup batteries allow operation after mine power is shut off in 

emergencies. Twenty-four hour backup is being provided per the 

NIOSH contract. 

A fully functioning pilot system is being installed in the Wolf 

Run Mining COp1pany's Sentinel Mine in early October 2008. 

An industry demonstration is planned for late October. The fixed 

node portion of the system has received MSHA approval as of 

September. MSHA approval of other system components is 

pending. Large scale commercial deployments will be possible in 

2009. L3 has a mine safety web site (L3 Communications, 2008). 
FIG 5 - Wireless mesh communication and tracking system. 

Kutta medium frequency system 

Through an interagency agreement (IAA) with the US Army, 

NIOSH has sponsored a modification to the development of a 

medium frequency system for use in underground coal mines. 

Medium frequency systems have an enormous potential as an 

emergency communications systems in a post-disaster scenario. 

The radios have been demonstrated to have a range of over two 

miles through 'parasitic propagation'. This is a characteristic of 

the radio energy that allows the energy to couple on to metallic 

structures in the mine, and be received anywhere along the path 

of the structure, as shown in Figure 6. 

FIG 6 - Kutta medium frequency system. 

The advantages of the medium frequency systems are severaL 

Active radio elements (radio transmitters or amplifiers) can be 

spaced a mile or more apart, which means far less active 

elements are required in the mine than with leaky feeder or mesh 

systems, which in tum means that less vulnerable infrastructure 

is required. Secondly, the radio propagation paths can be highly 

survivable and do not require power. Power lines for instance 

may be highly damaged but could still support medium 

frequency communications. Additionally, recent NIOSH tests 

have shown that a buried wire core life line or a single strand 

wire conductor provides an excellent propagation path with no 

observable degradation of the radio signal due to the wire being 

buried. Lastly, the medium frequency system is being designed to 

be interoperable with existing MSHA UHFNHF handsets that 

are used with leaky feeder systems, this will provide substantial 

flexibility in designing a practical cost-effective system. 

Interoperability with future systems such as wireless mesh 

systems and through the earth systems will be considered as 

these products become available in the market place. 

Initial preproduction models of the analog point to point 

medium frequency products will be received in April, and the 

delivery of the digital multi-hop products are expected in August. 

The system design has been submitted to MSHA for approval. 

A NIOSH-sponsored workshop on emergency communication 

and tracking is in the very early planning stages. This workshop 

would take place in 2009 and would include relevant results to 

date to aid mining companies in selecting and deploying systems 

best suited for their particular mine to meet MINER Act 

requirements. 

Analysis of belt air ventilation in coal mines 

In 2004 MSHA promulgated the final rule on belt air that 

allowed the use of belt entry air in the working sections in most 

mines. Last year as many as 157 underground coal mines in the 

US were using belt air. However, tragedies such as the Alma 

Mine No 1 fire in 2006 have raised questions about the safety of 

mine ventilation systems that use belt entry air. In the MINER 

Act of 2006, Congress required the establishment of a technical 

study panel on the 'utilisation of belt air and the composition and 

fire retardant properties of belt materials in underground coal 

mines'. The panel was charged with providing: 

... independent scientific and engineering review 

and recommendations with respect to the 

utilisation of belt air and the composition and 

fire retardant properties of belt materials in 

underground coal mining. 

The panel completed its report in December 2007 (Mutmansky 

et aI, 2007). As indicated by the MINER Act, MSHA proposed a 

new regulation on belt air in June 2008. One of the panel 

recommendations specifies that research is needed to reduce air 

leakage through stoppings placed between belt and intake entries. 
NIOSH has initiated a new research project to identify 

potential safety hazards associated with the use of belt entry air 

and develop engineering controls for reducing leakage through 

stoppings. The goal is to develop ventilation techniques that will 

improve miner safety if a fire occurs in the belt entry. The 

outcomes of the project will be a better understanding of leakage 

between entries, the benefits and disadvantages of booster fans in 

intake escapeways and a more thorough knowledge of ventilation 

scenarios, with computer modelling and general guidelines for 

using belt air. Results of the project are to provide information 

concerning these issues as a response to the research suggestions 

of the technical study panel and to enable re-evaluation of the 

current regulations concerning safety of using belt air for 

ventilation. The results also will be used to develop guidelines 

that will help mine operators using belt air to reduce the leakage 

into intake escapeways in case of a mine fire event and 

guidelines that will be helpful for monitoring air quality in belt 

airways to prevent hazardous situations in the belt entry. 

Reducing hazards of conveyor belt fires in 

underground coal mines 

The technical study panel also recommended studies on 

fire-resistant and fireproof belt materials, belt fire suppression 

systems, atmospheric monitoring systems and escapeway integrity 

to improve miner safety. While much progress has been made 

toward the prevention and control of fires in the mining industry, 

work is needed to evaluate new technologies and methods to 

implement the panel recommendations on conveyor belt fire 

prevention. NIOSH has begun another new research project to 

reduce the hazards of underground coal mine fires, particularly in 

conveyor belt entries by applying recent advances in the areas of 

fire-resistant and fireproof belt materials, belt fire suppression 

systems, atmospheric monitoring systems and computer codes for 

predicting and assessing in real-time the impact of fire on the mine 

ventilation system. The project will address the major issues 

concerning fires in underground coal mines, flammability of 

conveyor belts, detection, suppression systems, fire modelling of 

conveyor belts, fire modelling of contaminant spread and training 

and maintenance. It is expected that the research output from this 

proposed project will substantially reduce the number of fires and 

injuries due to fire and significantly improve the level of fire safety 

in mines. 

Protecting miners during retreat coal mining 

of pillars 

The recent disaster at the Crandall Canyon, which was caused by 

catastrophic coal outburst during pillar recovery, has focused 

attention on coal mine ground control. Many questions are being 

asked about pillar design, bump prevention and the safety of 

retreat mining. These issues are central to the protection of every 

underground mineworker. As a result of Congressional mandate, 

NIOSH initiated a new project to enhance the safety of miners 

working in underground coal mines where retreat mining in room 

and pillar operations is utilised, particularly at depths greater 

than 1500 feet. The project will review the available NIOSH 

technology, update and improve it as necessary and transfer the 

results to the mining community. Specific activities will include 

updates to the NIOSH software packages that are currently used 

for pillar design, the development of bump prevention guidelines, 

an expansion of the NIOSH case history data bases of bumps and 

pillar performance and an intensive technology transfer effort. The 

project will be conducted in close cooperation with MSHA, 

university research partners, and the mining industry. Congress has 

requested a final report on this work no later than December 2009. 

Respirable dust control 

Dust compliance sampling data shows that elevated coal and 

silica dust exposures continue to occur for high-risk occupations 

in the coal and metal/non-metal mining industries. In addition, 

recent X-ray surveillance data reported by NIOSH has illustrated 

an increased CWP prevalence in coal miners employed in the 

southern Appalachian region of the US mining industry. In 

response, PRL has just begun a new project, 'State-of-the-Art 

Technology for Controlling Coal and Silica Dust in Mining'. This 

project will identify state-of-the-art dust control technologies for 

various mining methods (eg longwall, continuous miner, surface) 

and develop best practice documents that summarise these 

controls. These documents will be compiled into two information 

circulars for distribution throughout the coal and metal/non-metal 

mining industries. In addition, this information will be placed on 

the mining website and burned onto compact discs to facilitate 

use by our stakeholders. The information will also be formatted 

for presentation at dust control workshops. Workshops will then 

be presented in each MSHA district to further assist in the 

transfer of information to mine operators and mine workers. 

POSSIBLE FUTURE INFLUENCES ON UNITED 


STATES MINING 


S-MINER bill 

The Crandall Canyon mine disaster increased pressure in the US 

Congress for action to improve safety and health for American 

miners. In January of 2008 the House of Representatives passed 

a bill called the Supplemental Mine Improvement and New 

Emergency Response Act of 2007 or the 'S-MINER Act'. The 

bill would need to be passed by the Senate and signed by the 

President to become law. The S-MINER Act would have very 

significant impact on the American mining industry if it became 

final law. 

Some of the features of the S-MINER Bill passed by the 

House of Representatives include: 

• 	 Requires MSHA to more closely review retreat mining plans 

before approving them, to observe retreat mining operations 

when they begin to ensure they are being performed in 

accordance with the plans and that miners are properly 

trained. Additional review would be required when the 

mining depth exceeds 1500 feet. 

• 	 Would ensure that the final rules on seals meet the NIOSH 

recommendations and extend these rules to those 

underground metal and non-metal mines which face similar 

risks because they emit large amounts of methane gas. 

• 	 Would generally require ventilation stoppings to be 

constructed in solid cement block. 

• 	 Establishes a mandatory schedule to ensure underground 

mines move forward to use the new and safer generation of 

conveyor belts. These requirements would apply to both 

underground coal and underground metal and non-metal 

mines. 

• 	 Permits belt air only if: 

• 	 it is necessary for safety reasons, 

• 	 it is approved through the modification process (a caseby-case review in which the authorised miner 

representative may participate) and includes all the 

protections recommended by the technical study panel. 

• 	 Requires the coal industry to quickly begin installation of 

enhanced communication and tracking systems and to 

supplement th~ systems as NIOSH develops enhancements. 

• 	 Requires underground coal mines to provide breathable air in 

some other form, such as air cylinders or boreholes, until 

refuge chambers are installed. On chambers in particular, it 

specifies that at least one refuge chamber has to be located 

with 500 feet of the nearest open cross-cut. 
• 	 Permits the new continuous personal dust monitor to be used 

to determine compliance with the respirable coal mine dust 

standard. It also cuts the exposure limits for respirable coal 

mine dust and silica in half. 

• 	 Requires MSHA to accept the scientific recommendations of 

NIOSH to update health hazard exposure limits, while 

ensuring that feasibility concerns are fully considered. 

CONCLUSION 

The US mining industry is in a state of flux following the coal 

mining disasters that occurred in 2006 and 2007 and the resulting 

changes in legislation and regulations. It is likely that the next 

Congress in 2009 will consider significant changes in mining 

health and safety legislation. The exact nature of that legislation 

is very uncertain at this time. In any case the mining industry is 

expected to grow and research needs that have been discussed in 

this paper will have to be addressed by NIOSH and others in the 

next few years. 

ACKNOWLEDGEMENT 

The Australasian Institute of Mining and Metallurgy copyright 

does not extend to this article with the United States of America. 

REFERENCES 

Harris, M L, Sapko, M J, Cashdollar, K L and Verakis, H C, 2008. Field 

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