PRV Vent Pipe Termination Above roof???

[teekaypl]

Gentleman,

What is an acceptable termination point above roof for the vent pipes for PRVs? Any help with this would be greatly appreciated, thank you.

-Tom

 

[UtilityLouie]

I think the most straightforward answer is the termination point needs to be where it cannot do harm when a release occurs.

In my opinion, that would mean a straight up discharge would need to be terminated 8' above the roof.

 

[Cuemaster64]

I would tend to agree with UtilityLouie about the height being greater than a man could reach but I will give you an example of one that is not. If the prv has a great discharge size and then the attatched piping triples in size and has a greater volume than what could be released and or has a low velocity then it could be lower. One other thing to consider is what you are actually releasing through your prv. Depending on whether it is immenently dangerous to health your height might have to be even higher so that no single person can place themselves in harms way to purposly injure themselves. I believe that NG and LPG have Jurisdictional Codes. Maybe these thoughts will help.

Eric

 

[specwrit]

Will the PRV be venting a product or is the vent only to allow the diaphragm to breath?
Many pressure reducing valves have vents that require to only breath with atmosphere. In this case, a screen will do.
If the vent is for an internal relief of product,then local codes would prevail for the product being released.

 

[pennpiper]

Tom "teekaypl"
Your question:
"What is an acceptable termination point above roof for the vent pipes for PRVs? Any help with this would be greatly appreciated, thank you."

Did not give us proper data needed to give a proper answer.
Example:
- Is the state of the commodity being released a Fluid or gas?
- Is the commodity a hydrocarbon or a toxic chemical
- What is the temperature of the release?
- What is the country where this project is located?
- Roof of what kind of building?