G3 G3 - Gas Technician Level 3 Pressure Regulation and Control Questions and Answers

Question 1

What is the primary function of a gas pressure regulator?

Accepted Answer

To reduce and maintain a constant downstream gas pressure regardless of upstream fluctuations

Answer

To increase gas pressure for high-BTU appliances

Answer

To measure gas consumption

Answer

To filter debris from the gas supply

Question 2

In a two-stage gas distribution system, the first-stage regulator typically reduces line pressure from high pressure to approximately:

Accepted Answer

2 psi (medium pressure)

Answer

0.25 in. W.C.

Answer

60 psi

Answer

7 in. W.C.

Question 3

The outlet pressure for most residential gas appliances in the US served by natural gas is typically:

Accepted Answer

3.5 in. W.C. (approximately 0.87 kPa)

Answer

2 psi

Answer

14 in. W.C.

Answer

60 psi

Question 4

A pressure regulator that allows outlet pressure to rise above its set point when gas flow stops is said to exhibit:

Accepted Answer

Creep

Answer

Lock-up

Answer

Droop

Answer

Surge

Question 5

What is 'droop' in the context of a gas pressure regulator?

Accepted Answer

The decrease in outlet pressure that occurs as gas flow demand increases

Answer

Physical sagging of the regulator body

Answer

An increase in outlet pressure at high flow

Answer

A regulator vent blockage condition

Question 6

A regulator vent must be positioned so that:

Accepted Answer

It is protected from weather and insects while allowing free discharge of gas

Answer

It faces upward to collect rainwater

Answer

It is sealed completely to prevent gas escape

Answer

It faces the appliance it serves