Regulations for Boiler Safety Valve.

1. Each Boiler (including EGB) is to be fitted with at least 1 safety v/v & where the water heating surface area is more than 46.5 m²,2 or more safety v/vs are to be provided. (Quick calculation of water heating surface area= π × D ×l× N (N= no of tubes)  
2. The safety v/v bore must be between 19mm-102mm  
3. Accumulation pressure test: with the steam stop v/v shut & the boiler burner firing continuously at full load capacity, the maximum pressure built up in the boiler should not exceed 6% of the maximumallowable working pressure. During this period feed water can only be admitted for safety reason only.  
4. The aggregate (total) relieving capacity of the safety v/v’s must not be less than the evaporating capacity of the boiler under maximumoperating conditions.  
5. Each boiler safety v/v is to be fitted with an easing gear by which the safety v/v can be operated from a safe platform either by hand or by mechanical means. 
6. The area of the escape pipe has to be equal or greater than the combined outlet area of the two safety v/v’s. The pipe should be free of any restriction.
   

Test name	Where  applicable	Pressure
Hydrostatic pressure test	Boiler pressure part (shell)	1.5 times ×M.A.W .P for 30 min
Accumulation pressure test	Safety v/v	Should not exceed 6% M.A.W.P
2ND safety v/v setting	2nd safety v/v	3% more than previous v/v
Main steam stop v/v test	Main steam stop v/v	1.5 × x (where the v/v is xk 200)
Water heating surface area , if more than 46.5 m2 , 2 safety v/v needed ,safety v/v bore must be between 19 to 102 mm.