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Repair Garage Oil Interceptor

Mech

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Joined
Oct 30, 2009
Messages
1,037
Location
Eastern PA
Section 1003.4.2.2 of the 2018 IPC calculates the oil separator capacity based on "the area to be drained."

Do you calculate only the sloping floor area adjacent to a trench drain, say 4 ft on either side, or do you include the flat areas at each repair bay as well?

I have always used the entire floor area of the service bays, whether flat or level. On a current project, a 2,000 gallon separator will be required. By using only the sloping floor surfaces, we can get away with a separator probably half the size. There will be hose reels, so I imagine the entire floor can or will be washed down, even if they need to squeegee the water to the drains.

Thanks in advance.
 
There might be some leeway given to bays that seldom see oil. Is there a lift or an alignment rack in the bay. Of course the layout can change. I took out the alignment rack for a car wash....way more money in washing cars.
 
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Mech, ...IMO, I would go with the entire area of the bay.

Whose to say that some oil and other petroleum products
will never be spilled in areas away from trench drain ?........Heck,
there might even be some petroleum products on the walls

& ceiling.

Costs should not be the deciding factor..........Actual, real
world experience of capturing any \ all of the contaminants
would, IMO, ...necessitate the larger sized interceptor.


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