This paper will address the requirements for the best practices in air quality testing for underground environments. Regulations that apply for tunnels are found in CFR 29 1926 Subpart S. The Mining regulations are found in Title 30 CFR 1 through 199. Please note that confined spaces are located in 29 CFR 1926, and have very different requirements than the tunneling and mining regulations. Confined spaces are dealt with in a more restrictive manner than tunnels and mines. The regulations variations indicate attention to the needs of the individual industries and the measures enacted to prevent injury and work place illnesses. We will discuss underground ventilation and the calculations required to perform accurate tests of airflow. Some attention will be provided to testing equipment, and we will address some typical problems encountered in the evaluation of underground environments.
It is important to identify the requirements for determining if an employee would be a good gas tester. Any potential gas tester must have adequate written and verbal skills. The tester will need to complete reports that detail conditions and locations where tests were performed. The descriptions should be simple, understandable and flow easily from one situation or test location to the next. Selections of any candidate should address levels of knowledge and understanding of: formulas, methods, equipment instruments, engineering controls, work practices, protective equipment, and statutory codes. Further, you should verify each potential candidate's understanding of: gas testing; ventilation measuring instrument operation, calibration and maintenance; in order to create a development plan for them so they may perform at the level of competency required to protect lives in underground environments.
Remember that in underground environments the following requirements must be followed for equipment used underground:
Diesel equipment must be permissible, and utilize water bath scrubbers or another permissible scrubber.
Conform to Class I Division II for gassy environments or Class I Division I for dusty environments.
All hot work must be performed by permit only!
All equipment, which could ignite a combustible atmosphere must be permissible. MSHA has identified which equipment is considered permissible for use in underground environments. Basically permissible equipment will not ignite in a flammable, combustible, or dusty atmosphere underground.
Lighters, matches or smoking materials
Strikers without hot work permit
Gasoline powered equipment and flammable fluids
Visitors without permits and escort
Electrical work without hot work permits