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Mine Safety and Health Administration, Labor.




Section 101(c) of the Federal Mine Safety and Health Act of 1977 and Title 30 of the Code of Federal Regulations Part 44 govern the application, processing, and disposition of petitions for modification. This notice is a summary of petitions for modification submitted to the Mine Safety and Health Administration (MSHA) by the parties listed below.


All comments on the petitions must be received by MSHA's Office of Standards, Regulations, and Variances on or before December 19, 2016.


You may submit your comments, identified by “docket number” on the subject line, by any of the following methods:

1. Electronic Mail: Include the docket number of the petition in the subject line of the message.

2. Facsimile: 202-693-9441.

3. Regular Mail or Hand Delivery: MSHA, Office of Standards, Regulations, and Variances, 201 12th Street South, Suite 4E401, Arlington, Virginia 22202-5452, Attention: Sheila McConnell, Director, Office of Standards, Regulations, and Variances. Persons delivering documents are required to check in at the receptionist's desk in Suite 4E401. Individuals may inspect copies of the petitions and comments during normal business hours at the address listed above.

MSHA will consider only comments postmarked by the U.S. Postal Service or proof of delivery from another delivery service such as UPS or Federal Express on or before the deadline for comments.

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Barbara Barron, Office of Standards, Regulations, and Variances at 202-693-9447 (Voice), (Email), or 202-693-9441 (Facsimile). [These are not toll-free numbers.]

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I. Background

Section 101(c) of the Federal Mine Safety and Health Act of 1977 (Mine Act) allows the mine operator or representative of miners to file a petition to modify the application of any mandatory safety standard to a coal or other mine if the Secretary of Labor determines that:

1. An alternative method of achieving the result of such standard exists which will at all times guarantee no less than the same measure of protection afforded the miners of such mine by such standard; or

2. That the application of such standard to such mine will result in a diminution of safety to the miners in such mine.

In addition, the regulations at 30 CFR 44.10 and 44.11 establish the requirements and procedures for filing petitions for modification.

II. Petitions for Modification

Docket Number: M-2016-007-M.

Petitioner: Vulcan Construction Materials, LLC, 11020 David Taylor Drive, Suite 105, Charlotte, NC 28262.

Mines: Enka Quarry, MSHA I.D. No. 31-00084, located in Buncombe County, North Carolina; Rockingham Quarry, MSHA I.D. No. 31-00198, located in Richmond County, North Carolina; Lenoir Quarry, MSHA I.D. No. 31-01094, located in Caldwell County, North Carolina; Penrose Quarry, MSHA I.D. No. 31-00111, located in Transylvania County, North Carolina; East Forsyth Quarry, MSHA I.D. No. 31-01919, located in Forsyth County, North Carolina; Cabarrus Quarry, MSHA I.D. No. 31-01357, located in Cabarrus County, North Carolina; and Clear Creek Quarry, MSHA I.D. No. 31-02087, located in Mecklenburg County, North Carolina.

Regulation Affected: 30 CFR 56.13010 (Reciprocating-type air compressors).

Modification Request: The petitioner requests a modification of the existing standard to allow the designated compressors outlined in this petition to be considered in compliance with the existing standard. The petitioner states that:

(1) The compressor industry guidance has shown that the high temperature shutoff switch is not offered as a standard safety feature on an electrically motor-driven reciprocating-type air compressor between 2 horsepower and 30 horsepower. The only time a high temperature shutoff switch is used on a reciprocating-type compressor is when very large compressors (100 horsepower and up) are housed in buildings or containers that could allow intake air to be heated by other environmental influences. However, a high temperature shutoff switch has always been standard for a rotary or screw type compressor that is working off of a combustion engine. When discussing this standard with compressor manufacturers, the first statement that is often made is “are you sure we are referring to a rotary compressor not a reciprocating compressor”.

(2) The petitioner states the following facts related to electric motor-driven reciprocating air compressors:

(a) The electric motor does not affect the temperature of the air in the compressor. The compressor and motor are only connected to sheaves on both sides.

(b) Existing 30 CFR 56.13010 states that the temperature switch must be adjusted to shut down the compressor when the normal operating temperature is exceeded by more than 25 percent. This would be virtually impossible because the normal operating temperature is affected by the intake air temperature which can fluctuate by 30 percent or more depending on the geographic location of the air compressor and the time of the year. According to manufacturers, the temperatures of supplied air can typically range from 32 degrees Fahrenheit to 115 degrees Fahrenheit. Due to the fluctuation in temperature ranges, the system could almost never be set to the actual 25 percent above normal temperature. In addition, the temperature of the intake air affects the density of the air which changes the amount of air being compressed during the process. The phenomenon directly affects the output temperature of the air.

(c) High temperature shutoff switches are considered unreliable in many applications because there is no true way to test whether the switch is actually working. To test a high temperature shutoff switch, the temperature would have to be altered to determine if the switch is working properly, which raises safety concerns.

(d) High temperature switches are also very costly and in cases where it was not provided as standard equipment by the manufacturer, installing a switch could void warranty and UL listing of a compressor if not installed by a certified manufacturer's representative. Not all States have compressor inspection programs, which could potentially allow an unqualified person to install a switch to meet the MSHA standard resulting in potential hazards to persons from a possible faulty installation.

(e) The units included in this petition currently are equipped with multiple safety features that include most of the following:

—Magnetic starter—prevents motor from electrical overload.

— Low oil level switch—prevents unit from operating in low oil conditions.

— Aftercoolers—cools discharge air that allows moisture to condense in the tank.

—Automatic condensate drain—ensures removal of water from tank.

—Unloader valve—relieves pressure on compressor head when unit shuts off. This prevents unit starting underload.

—Safety relief valves—relieves tank pressure at a set PSI to prevent over pressurization of tank. Line pressure relief valves are also utilized at aftercoolers.

—Tank pressure switch—cuts off pressure at a set normal PSI range.

—High amp fuse—cuts off motor if high amps are achieved.

The petitioner further asserts that industry data suggests that the current safety devices as equipped on the compressors offer equal protection to the standard even if they are not equipped with the automatic temperature actuated shutoff mechanism.

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Sheila McConnell,

Director, Office of Standards, Regulations, and Variances.

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[FR Doc. 2016-27714 Filed 11-17-16; 8:45 am]