Episode 6: Vacuum Leak Check of a Method 5 Sampling Train
We look at why and how we leak check an EPA sampling train under vacuum. What you should learn:
1) If a test run is conducted at an average sampling rate of 0.25 cfm, what is the minimum leak rate allowed by EPA Method 5?
a) 0.01 cfm
b) 0.02 cfm
c) 15 inches vacuum in 60 seconds
d) not enough information
2) If a test run fails the post-test leak check criteria of Method 5, you should fix the leak and repeat the leak check at a higher vacuum.
3) A vacuum leak check evaluates the air tightness of the entire sampling apparatus except the connection between the nozzle and probe. (T/F)
4) Which direction should you turn the bypass valve when conducting a leak check?
5) When is it recommended but not mandatory to leak check a Method 5 train:
a) Before the test
b) Before a component change
c) After a component change
d) After the test
e) a and c
f) b and d