Plumbing Gas Piping Systems 3

Question 1

What is the safe, approved method for detecting a gas leak at a fitting or connection?

Accepted Answer

Apply soapy water and watch for bubbles

Answer

Applying an approved leak detection solution or soapy water to fittings and observing for bubbles is the safe standard method — open flames are extremely dangerous.

Question 2

What additive is mixed into natural gas to give it its distinctive warning odor?

Accepted Answer

Mercaptan (ethanethiol)

Answer

Mercaptan (ethanethiol) is added to otherwise odorless natural gas so people can detect leaks by smell before concentrations reach dangerous levels.

Question 3

What is the maximum allowed length for a flexible gas connector hose to a residential appliance?

Accepted Answer

6 feet

Answer

Most codes limit flexible gas connectors to 6 feet maximum to reduce the risk of mechanical damage, kinking, or accidental disconnection.

Question 4

Why must CSST (corrugated stainless steel tubing) gas piping be bonded to the electrical grounding system?

Accepted Answer

To protect the thin stainless steel walls from damage caused by lightning-induced electrical arcing

Answer

CSST's thin corrugated stainless steel walls are vulnerable to arcing from indirect lightning strikes, which can burn through the material and cause gas leaks; bonding diverts this energy safely.

Question 5

What action must be completed before a gas system is returned to service after any repair?

Accepted Answer

Pressure test the system and inspect all connections for leaks

Answer

After any gas piping repair, the system must be pressure tested and all joints inspected for leaks before the gas supply is restored and the system is placed back in service.

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Plumbing Gas Piping Systems 3