Chains, Ropes, and Slings Test II
Source: Questions and answers from the National Safety Council


Progress Indicator:
Question 3 of 22

3.  The basic principle underlying mine ventilation is that air always moves __________.

Choices:
  1. when the fan is operating
  2. wherever the permanent controls direct it to go
  3. from high pressure regions to low pressure regions
  4. toward the working faces
  5. None of the above


See more about these products