Emergency Eye Wash Water Flow

[tebbensm]

I am designing instantaneous electric water heaters for an army guard unit hanger that has 6 eye washes, installed 15 years ago.
These are just Eye washes, but when measured they are flowing 3 GPM, in lieu of the .4 GPM minimum?
Pressure in the building is 63 PSI.
Maintenance is hesitant to reduce the flow to the eye wash claiming they may not achieve the correct stream characteristics.
I called Bradley and Haws, asked if these units should operate correctly at .4 GPM, lots of evasive answers.
Has anyone had this experience?

 

[MikeHalloran]

Uh, 3 gpm handily exceeds a 0.4 gpm minimum.
Why would you attempt to reduce the flow?


Mike Halloran
Pembroke Pines, FL, USA

 

[catserveng]

Take a look here under "flushing and flowrate requirements"

http://www.selectsafetysales.com/t-emergency-eyewash-requirements.aspx

You need to provide enough flow to wash away the contaminant, but you also need to keep the velocity of the wash water low enough as not do further damage to the eyes.

I went thru this several years ago, depends on what you actually call the wash station, as an "eye wash" station has different requirements than an "eye/face wash" station.

Hope you find the link helpful, MikeL.

 

[PEDARRIN2]

Are you sure it is just an eye wash and not an eye/face wash? They can be difficult to differentiate. An eye wash is rated for 0.4 gpm minimum, but the eye/face wash are rated for 3 gpm minimum.

Take a look at the instantaneous water heater information. They should have a minimum turn on flow. If you need 0.4 gpm, there are heaters rated for that.

Personally, I would not go down to 0.4 gpm if that is what the existing are flowing. Pick a heater that will work at that flow rate.

 

[bimr]

Agree that the flow should be "Unit delivers at least 0.4 gallons (1.5 liters) of water per minute for 15 minutes. (Section 5.1.6, 5.4.5". ANSI Z358.1-2014.

There should be a test gauge to check the water flow: Water flow covers area indicated on test gauge at no more than 8” above spray heads. Contact the manufacturer.

 

[tebbensm]

Thanks to all for the quick response.
I should have mentioned that I did check the old O&M manuals to verify these units are indeed Eyewash only, and not Eye/Face wash.
Reasoning for reducing the flow is to reduce the size of the instantaneous water heater.
I agree it would be pertinent to design for the actual flow.
My curiosity now is: ("why are these units operating at 3 GPM when they should perform at .4 GPM?)
More concerning, these are existing units, I have been able to measure the actual flow and can size the instantaneous heater appropriately.
However, how would one size a heater for a new eyewash unit? Mfg literature indicates .4 gpm, but what I see is that this could vary by almost 10x?

For this project I will go back to the site and do some trial and error testing.

 

[PEDARRIN2]

Current designs have internal flow controls which can limit the flow rate.

Maybe these did not have them or they were removed during installation.

 

[MJCronin]

You may want to reconsider designing you own equipment. Several vendors (HAWES)offer electric water heaters and certified tempering valves.

http://www.globalindustrial.com/p/s...dHF7nEL7ixw3jpor57x9-K2DhZ4sP3E_fYBoCTPHw_wcB

http://www.eyewashdirect.com/Acorn-...=pla&catargetid=120205750000017774&cadevice=c

I assume that you are trying to supply tepid water for the eyewash stations.

Suggest that you also become familiar with the ANSI standards

http://www.eyewashdirect.com/ANSI-Eyewash-Z358-Eyewash-Standard-Guide-s/31.htm

MJCronin
Sr. Process Engineer

 

[dbill74]

I am inclined to side with maintenance and think you won't get proper stream characteristics out of the units.

It would be akin to putting a 1.28 GPF flush valve on a water closet design to work with 1.6 GPF. It won't get all the crap out.

 

[IRstuff]

What were the OSHA, or whomever, requirements from 15 years ago? A lot of things could have changed in the intervening decade and a half.

You say you looked at the O&M manual; what was the flow rate specified therein?

TTFN
I can do absolutely anything. I'm an expert!
faq731-376 forum1529

 

[bimr]

The manufacturer should be able to supply you with a test gauge to check the water flow: Water flow covers area indicated on test gauge at no more than 8” above spray heads.

If the eye wash is flowing at 3 gpm, the water should be coming out like a fountain.

 

[dicksewerrat]

Make sure the maintenance guys wash their eyes before anyone else does. 3 gpm seems like a fast moving stream coming out and blasting into a delicate eyeball. Call your eye doctor and ask him what the proper speed of a stream of water for the eye.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[dcaan]

You can install a pressure reducer or pressure regulator in the pipeline before the inlet of eye wash but it will give you additional cost.

 

[MJCronin]

Ripout all of the old stuff ..... install all-new, pre-OSHA certified, guaranteed, tested UL approved new stuff

MJCronin
Sr. Process Engineer