|U.S. Department of
Mine Safety and Health Administration|
1100 Wilson Boulevard
Arlington, Virginia 22209-3939
|EFFECTIVE DATE: July 19, 2006
||EXPIRATION DATE: 03/31/2008|
(Reissue of I03-
PROCEDURE INSTRUCTION LETTER NO. I06-V-7
FROM: RAY McKINNEY
for Coal Mine Safety and Health
SUBJECT: Supplemental Roof Support Materials
This Procedure Instruction Letter (PIL) provides instructions to Mine Safety and Health Administration (MSHA) personnel responsible for enforcing the requirements of Title 30 Code of Federal Regulations (30 CFR) § 75.214, and reviewing and evaluating new and revised roof control plans for underground coal mines to insure the plans are suitable to the prevailing mining conditions.
This PIL will assist MSHA enforcement personnel in determining the location, type, and quantity of supplemental roof support required at a particular mine and whether the supplemental roof support materials should be identified in the mine's roof control plan.
30 CFR § 75.214, " Supplemental support materials, equipment, and tools" provides that:
(a) A supply of supplementary roof support materials and the tools and
equipment necessary to install the materials shall be available at a
readily accessible location on each working section or within four
crosscuts of each working section.
(b) The quantity of support materials and tools and equipment maintained
available in accordance with this section shall be sufficient to support
the roof if adverse roof conditions are encountered, or in the event of an accident involving a fall.
Mines using traditional roof bolting systems typically maintain wooden props/posts, cribs, cap pieces, wedges, and crossbars with the tools necessary for installation on the section for use as supplemental roof support. In these
situations, it is normally not necessary to address supplemental support material in the roof control plan as the identification of those materials and the quantity necessary at the mine is apparent to the inspector and miners.
Other mines may use more complex and sophisticated roof support systems including cable bolt systems, resin grouted roof bolts and trusses, tensioned bolting systems and conventional point anchor bolts, steel friction props, machined wooden cribbing and cementatious cribbing. The distinction between required support components and supplemental support components may become blurred and lead to confusion on the part of inspectors and miners. Where these conditions exist, the District Manager will examine the mine's roof control plan to determine whether the plan should clearly identify which components are present to meet the supplementary support requirements of
30 CFR § 75.214. For both initial plan approval as well as the semi-annual review, District Managers, as part of the approval process, will determine whether additional supplemental support is necessary, whether additional supplemental support requirements should be added to the roof control plan, and whether the supplementary support materials and equipment required under 30 CFR § 75.214 should be identified in the roof control plan. This review will assure that the plan is suitable to the geological conditions and the mining system used at the mine, and assure that additional measures are available to protect persons if unusual hazards are encountered. In addition, during the plan review, the District Manager will take into consideration any falls of the roof, rib, or face and the adequacy of the support systems used at the mine.
Supplemental roof support materials and the tools and equipment necessary to install them should be regularly examined during mandatory inspections to assure that supplies have not been used, lost, or misplaced. These materials must be available in sufficient quantity and in a readily accessible location to support the roof if adverse roof conditions are encountered or a roof fall accident occurs.
This PIL provides directions for inspectors to assure that the standard is being applied properly and uniformly.
The Federal Mine Safety and Health Act of 1977, 30 CFR § 75.214(a) and (b), 75.220(a)(1), 75.221(a)(5), 75.222(a), and 75.223(d).
This PIL should be filed behind the tab marked "Procedure Instruction Letters" in the binder entitled Program Handbooks and Procedure Instruction Letters.
Issuing Office and Contact Person
Coal Mine Safety and Health
James G. Vadnal, (202) 693-9505
This PIL, as well as the Program Policy Manual, may be viewed on the Internet by accessing MSHA's web site (http://www.msha.gov), click on "Compliance Info" and then "Procedure Instruction Letter."
MSHA Program Policy Manual Holders
Underground Coal Mine Operators
Coal Special Interest Groups