ISSUE DATE: 12/16/10 EXPIRATION DATE: 03/31/2012
Administrator for Metal and Nonmetal
Mine Safety and Health

SUBJECT: Determining compliance under 30 C.F.R. §§ 56.5002 and 57.5002

This Procedure Instruction Letter (PIL) applies to all Metal and Nonmetal Mine Safety and Health enforcement personnel. This PIL applies to those air contaminants covered under 30 C.F.R. §§ 56/57.5001(a) and (b) and does not apply to standards for radon, diesel particulate matter, or noise since those standards contain specific monitoring requirements.

The purpose of this PIL is to provide instructions to inspectors on MSHA’s standards for surface and underground metal and nonmetal mines pertaining to surveys for airborne contaminants under 30 C.F.R. §§ 56/57.5002.

Procedure Instructions
Inspectors should consult with their supervisors, the district health specialists, or appropriate personnel from the Division of Health or the Directorate of Technical Support in their review and evaluation of an operator’s procedures for conducting
In reviewing operator procedures for implementing 30 C.F.R. §§ 56/57.5002, inspectors
should determine the following:
(1) Is the operator conducting surveys?
Inspectors should determine if surveys are being or were conducted (e.g. employee knowledge, records, management knowledge, general appearance of the facility). Inspectors should consider any methods used by the operator in determining whether surveys are being conducted.
(2) If MSHA sampling indicates an overexposure, inspectors should consider the adequacy and frequency of surveys.
(A) Are the surveys being conducted adequate for determining whether controls are effective in reducing exposure to airborne contaminants?
i. Should determine the type of surveys that are being conducted.
Quantitative surveys include exposure monitoring/sampling, and wipe
sampling. Qualitative surveys include vehicle maintenance, ventilation system maintenance, dust control system maintenance and walk-through inspections.
ii. Is the person conducting the survey properly trained?
iii. Are the quantitative surveys consistent with established scientific principles (e.g., NIOSH recommended methods found at or is control equipment (e.g. vehicle cabs, dust control systems) maintained according to manufacturer's specifications?
(B) Are the surveys being conducted frequently enough for determining whether controls are effective in reducing exposures to airborne contaminants?
Inspectors should consider the following when determining whether frequency of the surveys is adequate:
i. Sampling results approach the Threshold Limit Value (TLV).
ii. Changes in the mining operation (e.g., hazards or environmentalagents).
iii. Changes in control equipment used to reduce exposures.
iv. Changes in the work schedule (e.g., if workers worked longer shifts) or work procedures.
v. Whether controls need routine or special maintenance of controls (e.g., vehicle cabs, ventilation systems, dust collection systems). If controlsystems are not properly functioning, then exposures to air contaminants may exist.
vi. Employee complaints, illnesses, or disease.

MSHA recently issued a Program Policy Letter on Mine Operator Requirements for Exposure Monitoring of Harmful Airborne Contaminants. Under 30 C.F.R. §§ 56/57.5002, a mine operator must conduct dust, gas, mist, and fume surveys as frequently as necessary to determine the adequacy of control measures.
The purpose of MSHA’s exposure monitoring standards is to help assure that the miners are not exposed to harmful concentrations of airborne contaminants.


The Federal Mine Safety and Health Act of 1977, as amended, 30 U.S.C. § 801 et. seq.,
30 C.F.R. §§ 56/57.5002.
Internet Availability
This PIL may be viewed on the Internet by accessing the MSHA home page ( then choosing "Compliance Info" and "Procedure Instruction Letters."
Issuing Office and Contact Persons
Metal/Nonmetal Mine Safety and Health, Division of Health
Reginald J. Richards, DrPH, CIH (202) 693-9632
Metal and Nonmetal Mine Safety & Health Enforcement Personnel
Office of Assessments Personnel