MSHA GAS DETECTION QUALIFICATION
TEST QUESTIONS AND ANSWERS
Any underground workers who are aware of unsafe situations that they are
unable to address while performing their regular responsibilities are required to
notify them right away. ANSWER The direct supervisor or mine foreman
What is the responsibility of the supervisor who receives reports of unsafe
situations or who observes them while doing his duties? ANSWER ensuring
that they are immediately fixed and that no one is put in danger other than what
is required to fix the condition
What is methane's explosive range? ANSWER 5–15%
What is methane's specific gravity? ANSWER.555
Does the working face's methane need to be kept below? ANSWER 1%
What should be done if methane levels are more than 1%? ANSWER A. The
ventilation system must be immediately modified or adjusted in order to lower
the methane content to less than 1.0% B. Until the methane content is below 1%
C, no additional work is allowed in the impacted region. 1. Everyone except
those mentioned in 104(c) of the Act must leave the affected area when 1.5% or
more methane is present in a working area, an intake air course, including an air
course where a belt conveyor is located, or in an area where mechanized mining
equipment is being installed or removed. 2. Electrically powered equipment in
the affected area must be disconnected at the power source, with the exception
of intrinsically safe AMS.
Where in the mine is methane most likely to build up? ANSWER Faces: section
and longwall, high spots, and long cross cuts
TEST QUESTIONS AND ANSWERS
Any underground workers who are aware of unsafe situations that they are
unable to address while performing their regular responsibilities are required to
notify them right away. ANSWER The direct supervisor or mine foreman
What is the responsibility of the supervisor who receives reports of unsafe
situations or who observes them while doing his duties? ANSWER ensuring
that they are immediately fixed and that no one is put in danger other than what
is required to fix the condition
What is methane's explosive range? ANSWER 5–15%
What is methane's specific gravity? ANSWER.555
Does the working face's methane need to be kept below? ANSWER 1%
What should be done if methane levels are more than 1%? ANSWER A. The
ventilation system must be immediately modified or adjusted in order to lower
the methane content to less than 1.0% B. Until the methane content is below 1%
C, no additional work is allowed in the impacted region. 1. Everyone except
those mentioned in 104(c) of the Act must leave the affected area when 1.5% or
more methane is present in a working area, an intake air course, including an air
course where a belt conveyor is located, or in an area where mechanized mining
equipment is being installed or removed. 2. Electrically powered equipment in
the affected area must be disconnected at the power source, with the exception
of intrinsically safe AMS.
Where in the mine is methane most likely to build up? ANSWER Faces: section
and longwall, high spots, and long cross cuts
