WorksheetsGas Pipework Installation Quiz no4
Total questions: 27
Worksheet time: 14mins
The maximum interval between horizontal pipework supports for 15 mm copper gas pipework installed between solid timber joists is:
1.0 m.
1.5 m.
2.5 m.
3.5 m.
The minimum size solid timber joist that can be notched for a gas pipe is:
50 mm.
75 mm.
100 mm.
150 mm.
Where gas pipework is buried in a floor screed, what is the minimum cover above the pipe?
5 mm.
10 mm.
25 mm.
100 mm.
Gas pipework installed behind dry lining shall:
Be made of steel only.
Need no additional protection.
Be suitably wrapped in tape only.
Be suitably encased by building material.
Gas pipework installed within walls of timber frame and light steel-framed construction shall:
Be made of steel only.
Have only welded joints.
Be left unsupported to allow for movement.
Be run within purpose-designed channels or ducts.
Above ground external gas pipework shall be protected against:
Painting
The weather
The risk of mechanical damage
The risk of unauthorised alterations
Polyethylene (PE) gas pipework in private gardens, with no vehicular traffic, shall have a MINIMUM depth of cover of:
375 mm with marker tape between 75 mm above the pipework
450 mm with marker tape between 75 mm above the pipework
375 mm with marker tape between 100 mm and 300 mm above the pipework
450 mm with marker tape between 100 mm and 300 mm above the pipework
Gas pipework shall not be installed under the foundations of a building unless:
Steel pipework is used
Buried 40 mm below the base concrete
Adequate steps are taken to prevent damage to the pipework
Polyethylene (PE) pipework is used and wrapped in corrosion resistant tape
For buildings containing flats and/or maisonettes gas pipework shall be fire stopped as it passes from one floor to another:
Unless constructed from welded steel
Only for buildings with three or more storeys
Only when they are in excess of 15 mm copper or ½” steel
Unless installed in its own protected shaft that is ventilated top & bottom to outside air
Gas pipework passing through a protected area shall NOT be of what type of material?
Continuous length of copper
Copper containing only mechanical joints
Steel pipework with screwed or welded joints
Continuous length of pliable corrugated (stainless steel) tubing (manufactured to withstand fire test A of BS EN 1775)
A typical method of accommodating movement for pipework passing through a timber frame / masonry wall is to:
Pass wrapped steel tube through the wall.
Pass sleeved polyethylene (PE) tube through the wall.
Pass sleeved pliable corrugated (stainless steel) tube through the wall.
Pass manufacturer wrapped copper tube to BS EN 1057 through the wall.
The approximate pressure loss between the meter outlet and the boiler connection on the natural gas pipework installation (incorporating 2 elbows) illustrated below is:
0.14 mbar.
0.40 mbar.
0.46 mbar.
2.20 mbar.
In multi occupied premises where gas is supplied to each individual dwelling by an external or internal riser there shall be an emergency control valve (ECV) installed:
Below the footpath as near as practical to the premises.
As near as practical to the point of entry to each dwelling.
In a locked compartment, accessible only to the gas transporter.
On the service pipe, as near as practical to its connection with the distribution main.
The procedures documented in which of the following standards shall be followed when tightness testing a domestic natural gas installation containing a G10 meter, 42 mm copper pipework and having a volume of 0.038 m³?
a) BS 6400
b) BS 6891
c) IGE/UP/1A
d) IGE/UP/1B
Unless otherwise specified by the manufacturer, any ELECTRONIC gauge used for the purpose of tightness testing, etc., should be calibrated at least every:
a) 3 months
b) 6 months
c) 12 months
d) 24 months
Several of the tests that may be undertaken when tightness testing specify the pass criteria as 'No Perceptible Movement'. When testing with a suitable ELECTRONIC gauge accurate to two decimal places, this means a gauge movement of:
a) 0 mbar
b) Less than 0.25 mbar
c) Less than 0.5 mbar
d) Less than 1.0 mbar
What is the maximum permissible pressure drop during the tightness test on an EXISTING gas installation consisting of an E6 (ultrasonic) meter, a maximum pipework diameter of 22 mm, a volume of 0.008 m³, appliances connected but NOT isolated and there is no smell of gas?
a) 0 mbar
b) 2 mbar
c) 4 mbar
d) 8 mbar
What is the maximum permissible pressure drop during the tightness test on an EXISTING gas installation within a flat that contains an additional emergency control valve (AECV), but NO meter, with a maximum pipework diameter of 15 mm, appliances connected but NOT isolated and there is no smell of gas?
0 mbar
2 mbar
4 mbar
8 mbar
What test medium may be used when testing a new installation before it is connected to a live natural gas supply?
Air
Nitrogen
Carbon Dioxide
Liquefied Petroleum Gas (LPG)
If, after the completion of a satisfactory tightness test, a smell of gas occurs around a lit appliance but disappears when the appliance is turned off the gas operative should:
Contact the Gas Safe Register
Notify the Health & Safety Executive (HSE)
Check pipework downstream (on the outlet) of appliance control taps, flame supervision devices, etc., with leak detection fluid
Contact the Emergency Service Provider (ESP) in order that they can check the service pipe upstream (on the inlet) of the gas meter / emergency control valve for gas escapes
When carrying out a tightness test on an installation supplied through an electronic token meter (ETM) the gas operative must ensure great care is taken to prevent the:
Gas pressure from falling below 24 mbar
Anti-tamper device on the meter activating, shutting off the supply to the installation
Anti-tamper device on the regulator activating, shutting off the supply to the installation
Anti-tamper device on the regulator activating, increasing the pressure to the installation
Which of the following is NOT a reason for the operating pressure at a gas appliance inlet being excessively low?
Incorrectly set primary meter regulator
Over-sized installation pipework between the meter and the appliance
Undersized installation pipework between the meter and the appliance
Partial blockage in the installation pipework between the meter and the appliance
What may be the effect of excessive burner operating pressure on a natural gas appliance?
Flame lift off.
Flame light back.
Increased appliance efficiency.
Improved combustion efficiency.
On a fanned flue boiler, what will the safety control circuitry prove prior to allowing the fan to run?
The flame rectification circuit is sensing a flame.
The fan is delivering an adequate draught / pressure.
The flue flow sensor is in the 'no flow' or 'no air' position.
The burner has modulated to give the correct heat output.
To ensure that any appliance can operate safely should the operating pressure on the outlet of an emergency control valve (ECV) drop to 19 mbar, the pressure absorption allowed across a primary meter installation, under maximum flow conditions, shall not exceed:
1 mbar
4 mbar
5 mbar
8 mbar
The outlet pressure on a low pressure primary meter installation is designed to be nominally 21 mbar, this pressure will fluctuate around the set point of the regulator dependant on the flow rate. The acceptable range of operating pressures in relation to flow rates is:
20 mbar at 0.5 m³/h and 22 mbar at 6 m³/h
22 mbar at 0.5 m³/h and 20 mbar at 6 m³/h
19 mbar at 0.5 m³/h and 23 mbar at 6 m³/h
23 mbar at 0.5 m³/h and 19 mbar at 6 m³/h
When ordering a spare part for gas appliances what information is normally required by the 'Spares Supplier' to ensure the correct component is obtained?
Where the appliance was purchased from.
Appliance net heat input in kW or gas rate in m³/h.
Appliance manufacturers address, the appliance colour and installation date.
Appliance details and serial number, part description and manufacturers part number.
