Engine 2014: Engineering Safety

1. A entry without a breathing apparatus may be made at the top of the tank, since petroleum vapors are heavier than air
2. B a person may work safely without breathing apparatus in cold weather, since the vapors are less volatile
3. C breathing apparatus would not be necessary, if expected to be in the tank for only a short period of time
4. D self-contained breathing apparatus should always be used

Tip: press A-D to answer