Dry risers play an important role in tall buildings by keeping the property safe from extensive fire damage as they allow the rapid deployment of fire hoses within a burning building by fire fighters. Buildings over 18 metres high will tend to have dry risers and those over 60 metres will have wet risers.
The typical check of a dry rising main will include;
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Checking valves open and close (leave closed, strap and lock). |
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Replacing damaged outlet instantaneous washers, missing blank caps and chains. |
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Checking that all hand wheels and nuts are undamaged and in place. |
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Checking the air release valve and replacing if necessary. |
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Checking the inlet cabinet and door for corrosion. |
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Checking that the inlet breaching valve springs and that the rubbers are free moving and in good condition. |
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Checking the glazing and sign in the door. |
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Removing any rubbish from the inlet box. |
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Lightly lubricating all moving parts. |
On completion of inspecting the system, water will be allowed to flow through for at least 5 minutes, discharging via the topmost outlet flushing out any debris that may be present (if possible).
The system will then be completely charged with water to a pressure of 3 bar (measured at the inlet), and all landing valves will be checked for leakage, and auto air purge will be checked for valve operation. Should this valve be found to be faulty, every attempt will be made to fit a new valve at the time of test.
The pressure will then be increased to 10 bar (measured at inlet) for a period of 15 minutes, during this time a further inspection of the system will be made to check for leakage of water at joints and landing valves. When the landing valve is replaced, all of these checks should be completed.
On completion of the static pressure test a flow test will be carried out. Water will be passed through the system under pressure for a period of not less than 5 minutes and flow gauge readings recorded on the Test Certificate. If unable to sustain an effective jet from the topmost outlet or if there is any undue pressure loss in the rising main (after allowing for the height involved) an investigation will take place.
If in doubt call for a quotation – we just need to know the location and how many floors there are in the building.
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 Click here to view a diagram of the typical arrangement of a dry rising main |
