Natural Gas Distribution Network Quiz

What is the purpose of pressure regulation in a natural gas distribution network?

• Close the supply.

• Ensure safe delivery.

• Prevent gas leaks.

• Open the supply.

What is the purpose of a pressure regulator fitted on the inlet to a primary gas meter?

• To maintain a defined pressure to a system, by adjusting the flow of gas.

• To adjust the pressure so that it meets the needs of the system design.

• To maintain and monitor pressure to a system, by cutting off the gas flow in an emergency.

• To remove pressure and prevent damage to the system in an emergency.

What is the most likely cause of pressure loss when carrying out a tightness test?

• An overrated gas appliance on the system.

• The regulator letting by during the test period.

• A gas escape somewhere on the system.

• The ECV letting by during the test period.

Which statement correctly describes how a dangerous occurrence could happen during the combustion process?

• Incomplete combustion due to insufficient oxygen, which results in carbon monoxide.

• Incomplete combustion due to excessive oxygen, which results in carbon monoxide.

• Incomplete combustion due to insufficient oxygen, which results in carbon dioxide.

• Incomplete combustion due to excessive oxygen, which results in carbon dioxide.

How is evidence of incomplete combustion on a gas appliance identified?

• A blue flame is present.

• The appliance is hot to touch.

• Noisy burner when in operation.

• Soot deposits around the appliance.

What is the required activation time for a carbon monoxide alarm, when exposed to a concentration of 100 ppm?

• Between 10 minutes and 40 minutes

• Within 10 minutes

• Between 45 minutes and 60 minutes

• After 60 minutes

A new hair salon has recently opened. A carbon monoxide detector in the salon is being activated intermittently during business hours. A new room-sealed appliance was recently installed on the premises; a gas-safe engineer has confirmed that the appliance is in good working order. What is the cause of this issue?

• Heat produced by electrical panel heaters.

• Aerosol products used on hair.

• Warm air currents from hair dryers.

• Bright lighting used during business hours.

What is a disadvantage of ‘Black-spot’ indicator cards?

• They have a short expiry date.

• They are not audible.

• They are difficult to see.

What type of burner is shown in Figure 1?

• Pre aerated burner.

• Forced draught burner.

• Post aerated burner.

• Atmosphere burner.

A customer has noticed a problem with an open flued gas boiler, after having the outside of their property covered with sheet cladding. The flame picture is yellow. Previously, it was blue. What is the cause of this problem?

• Heat loss through the external walls when the cladding was installed.

• Gas pipework has been obstructed by the cladding, preventing air circulation.

• Heat gain through the external walls when the cladding was installed.

• Obstruction of ventilation to the outside when the cladding was installed.