Eyewash Indirect Connection (Again) 3

[NEplantengineer]

Hello Folks,

For some reason my post back in Aug was deleted. I would like to pose the question again: Is the connection between the bowl drain of an eyewash and the sanitary system supposed to be an indirect connection or can the bowl drain be directly connected to the sanitary system (of course with proper trapping and venting)?

Thanks, Hugh

 

[PEDARRIN2]

Where I am, under the IPC, the drain from the eyewash can be connected directly to the sanitary system. I believe the other codes allow this also.

They do make them to indirect to a floor drain also. I have seen these when there is also a safety shower which typically drains to a floor drain. The rationale is why have two drains when one is acceptable.

 

[ChrisConley]

The rational for indirect, I believe, is that the fixtures are used so infrequently (read never) that the trap will invariably dry out over time. By draining indirectly to another trap the chance that the trap will be recharged with fresh water occassionally is increased.

Having said that, in Canada it is acceptable to either directly or indirectly connect an eyewash drain to the sanitary sewer. I've done both.

 

[PEDARRIN2]

The fixtures might not be used for their intended purpose, but I believe they have to be tested on a regular basis.

This testing should keep the trap primed.

 

[KRocker]

The IPC does not directly state the type of connection to the sanitary system. In fact 411.2 states: Waste connections shall not be required for emergency showers and eyewash stations. The thought behind this is that if there is an accident, it can be properly contained without affecting the sanitary system (mainly for chemical accidents & not fire).
Both ways are acceptable, giving the trap is primed. However, more consideration should be given to what is being discharged into the system, ie. a dedicated acid waste system to protect run off when fixture is in operation.

I only have to design by the IPC, so designing by local jurisdictions is crucial in determining the correct method.

 

[NEplantengineer]

Thank you folks for replying to this question. We went ahead and had the eyewash station in question connected to the waste system. The issue we have here is that we must test all eyewashes once a month. With somewhere around 500 units this is quite a job. With the eyewashes directly connected to the waste system, testing is a heck of a lot easier that capturing the water with a bucket. It may also help to encourage the local users to test their own eyewashes. I work under the MA plumbing code which also does not preclude one connecting an eyewash to the waste system. The question came up when a consultant during a lab renovation said we had to have an indirect waste connection. When pressed on this requirement he could not back it up with specific code language. His basic premise, however, was a sound one; you should not connect a fixture to the waste system unless it has been specifically designed to not contanminate the potable water during a waste system back-up. One of the ways you know if a fixture meets this requirement is looking for the ASTM 112.1.2 (I could not find this approval on any eyewashes) or at least checking to see that the min air gap is there. In the end the local AHJ will have the final say which I'm pretty sure will say okay since we have many other eyewashes directly connected to the waste system.
Thanks again for the feedback.

 

[PEDARRIN2]

The rationale is sound but if there are any floor drains or water closets or floor janitor's basins downstream of the eye wash and the proposed blockage, the waste would overflow those before reaching the level of the bowl.

In the event that nothing is downstream, the nozzles on the eyewash are above the flood level rim of the bowl so there would not be any contact between the backed up waste and the potable water.