Mine Rescue Field Exam
From the 2012 North Central Regional Mine Rescue Contest, Wilmington, IL


Progress Indicator:
Question 1 of 30

1.  The Threshold Limit Value (TLV) of a gas is:

Choices:
  1. the average concentration of a gas a worker is allowed to be exposed to
  2. the maximum concentration of a gas a worker is allowed to be exposed to
  3. the average concentration of a gas a worker is allowed to be exposed to over an 8-hour working period
  4. the average concentration of a gas a worker is allowed to be exposed to over his normal work shift