Module 5 Pipework and Fittings Flashcards
New gas pipework within dwellings cannot be made of lead, lead alloy or any non-metallic substance unless it is a flexible hose connected to a flueless, moveable gas appliance.
True or False?
True
When doing hot work in a small house can you leave the meter in place?
No, hot work within 10m of a meter means it must be removed and stored in a well ventilated area.
If you bury copper pipe work in a floor does it need protection from corrosion?
Yes, must have one of the following:
a) Factory bonded PVC coat
b) Sit in non corrodible duct/sleeve
c) Wrapped with corrosion resistant tape
When designing a new pipe installation what is the maximum pressure drop that is allowed?
1mbar
Name three points about pipework installed in ducts
1) Screwed or welded steel
2) Vent – top and bottom
3) Must not impair fire resistance of the structure
What distance is required between gas pipe and electrical installations?
a) Electrical meters / fuse boxes = 150mm
b) Electrical cables = 25mm
If the cross sectional area of a duct is 0.005m2 the ventailation free area required is:
a) none
b) Cross Sectional Area of duct
c) 0.05m2
d) 1/150 of cross sectional area of duct
a) none
If duct less than 0.01m2 no additional vent required
If the cross sectional area of a duct is 10m2 the ventailation free area required is:
a) none
b) Cross Sectional Area of duct
c) 0.05m2
d) 1/150 of cross sectional area of duct
d) 1/150 of cross sectional area of duct for each opening
Duct exceeds 7.5m2
If the cross sectional area of a duct is 2 the ventailation free area required is:
a) none
b) Cross Sectional Area of duct
c) 0.05m2
d) 1/150 of cross sectional area of duct
b) Cross Sectional Area of duct - each opening
For duct sizes between 0.01 and 0.05m2
What are the limits for drilling holes in a joist?
a) max diameter ¼ joist depth
b) between ¼ and 2/5 of length from edge
c) holes drilled halfway down
d) holes not closer than 3 x diameter from each other
What diameter cable should be used for cross bonding?
At least 10mm2
What is the maximum depth and how far from the edge can a notch be?
a) max 1/8 joist depth
b) max ¼ of length from edge
What is the interval for supporting copper pipe on a vertical run? 15mm, 22mm and 28mm
15mm = 2.0m
22 & 28mm = 2.5m
Why should surplus flux be wiped off?
To avoid corrosion in the future
What is the interval for supporting copper pipe on a horizontal run? 15mm, 22mm and 28mm
15mm = 1.5m
22 & 28mm = 2m
Where can’t compression fittings be used?
Where they are not readily accessible e.g. buried in a structure, below ground
In practise if a pipe passes through a cavity what do you do?
1) Take the shortest route
2) Use gas tight sleeve, sealed to wall at both ends
3) Seal gas pipe at the internal side only
If you lay a pipe in a solid floor what is the minimum screed depth?
Gas pipe work should be located 150mm away from a fuse box and 25mm from an electrical cable. If this is not practical what two options can be used?
1) Cover pipe with electrical insulating material
2) Separate pipe and fuse box with insulating material
Where should an emergency control valve be located?
As close a practical to the point of entry into the dwelling
Pipe work – which is preferred bends or elbow joints?
Bends
How close to the meter can you use TRAC pipe?
600mm – the first bit must be rigid pipework
Can you use PE pipe inside a property?
No
What is the minimum depth deep that a pipe must buried on the two places marked?
a) 375mm min open ground
b) 40mm min below concrete
Name four key points about an ECV
1) Must be accessible
2) Clearly labelled + how to use
3) Permanent handle / lever
4) Fall into the off position
Can hemp be used on threaded joints?
Only in conjunction with a thread sealing compound
For an internal meter how close should the bonding be?
600mm on the downstream side
The British standard specifications for pipes and fittings can be found in which module of the BPEC domestic gas safety manual?
Module 5
When pipe sizing a good rule of thumb is that for every 10kW how many m3/h of gas is required?
Just under 1 m3/h (0.94m3/h)
Where should a pressure test point be located in relation to an ECV?
a) Upstream
b) Downstream
c) Either up or down
b) Downstream
When altering existing pipe work what two key things do you need to do?
1) Tightness test IGE/UP/1B
2) Cross bonding
There is one exception that allows you to run gas pipe in the cavity. What is it?
For a fanned flued living flame effect fire which is designed to sit in the cavity wall
If the cross sectional area of a duct is 5m2 the ventailation free area required is:
a) none
b) Cross Sectional Area of duct
c) 0.05m2
d) 1/150 of cross sectional area of duct
c) 0.05m2 each opening
Ducts between 0.05 and 7.5m2
If a pipe passes through a cavity wall what are two key requirements?
1) Be protected against failure caused by movement
2) Escaping gas must not enter the cavity
What is the minimum sized joist that you can notch?
Depth = 100mm
If you sleeve a pipe what can you seal the end with?
Non-setting mastic
