From: Rita Kay Calhoun <r.calhoun**At_Symbol_Here**MOREHEADSTATE.EDU>
Subject: Re: [DCHAS-L] Ventilation calculator for chemical spills? (shower question)
Date: Thu, 22 Oct 2015 17:18:16 +0000
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Message-ID: BY2PR02MB2183AEA193991A41A6A453CE4270**At_Symbol_Here**

A couple of points.

                As has been discussed on this listserv before, the “rinse” water will be so dilute that the is no concern about it draining into the sewer.

                If your building is like most, water on the floor of a 3rd story lab will soon end up on the 2nd floor, etc.

                Not all accidents happen when Facilities people are available with a shop vac.  By the way, if you’re still concerned about the water going down a floor drain, realize that the shop vac will be emptied down a sink drain.

                It is true that the flow rate of the floor drain is probably less than that of the shower, it still helps.


Personally, I think it is foolish not to have floor drains.





From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**]On Behalf Of bkgarebe
Sent: Thursday, October 22, 2015 12:27 PM
Subject: Re: [DCHAS-L] Ventilation calculator for chemical spills? (shower question)


Hi Don, 

My main point was where would these volumes of water drain to?







Sent from my Samsung device

From: Don Abramowitz <dabramow**At_Symbol_Here**BRYNMAWR.EDU>
Date: 22/10/2015 18:12 (GMT+02:00)
Subject: Re: [DCHAS-L] Ventilation calculator for chemical spills? (shower question)


Emergency showers under ANSI standards are supposed to provide a flow of 20 gallons per minute for at least 15 minutes.  I'm hoping those numbers are helpful in defining quantities for your circumstances. 

That's a fair bit of water, and apart from the several issues around where the water goes if there are no drains, I wouldn't be too concerned about standing in the contaminated water after, in this case, 300+ gallons of rinse water mixes with the relatively small volume of contaminant present on a person's skin or clothes.   That will reduce the concentration of anything miscible with water by several orders of magnitude, while such other measures are going on, such as removing contaminated clothing and moving out of the immediate area once the rinsing is completed.


Donald Abramowitz, CIH
Environmental Health & Safety Officer
Bryn Mawr College
Bryn Mawr, PA




Can anyone pls assist me urgently. I head an Occupational Health Analytical Laboratory facility in Johannesburg. We are about to take over a newly renovated organic chemistry lab. An emergency shower has been installed, but with no drainage. We are being told that that is the norm in South Africa.


Apparently, the General Safety Regulations framed under the OHS Act, Regulation 3 (9) states that “Where an employee at a workplace is exposed or can be exposed to a potential hazard of injury to or absorption through the skin as a result of sudden contact with a large amount of toxic, corrosive, high risk or similar hazardous substance, the employer concerned shall make sure that there is a fast-reacting deluge-shower with clean water or a similar facility in the immediate vicinity of the workplace of such employee and that the employee is trained in the use thereof.” There is no definition of large amount and again no reference to drainage to sewer (or otherwise).

I disagree since this would mean that in the event (hopefully rare) of an accident, an employee will wash off the contaminant and still "stand" in the contaminated water. How are your emergency showers configured?



Boitumelo Kgarebe

National Institute for Occupational Health

Johannesburg, South Africa 


On Tue, Oct 20, 2015 at 8:50 PM, Secretary, ACS Division of Chemical Health and Safety <secretary**At_Symbol_Here**> wrote:


I am looking for a good industrial hygiene resource for calculating the evaporation rates of a spilled chemical and the amount of ventilation required to keep the chemical spill below the specific chemicals OSHA PEL (ppm).  Does anyone know of any good computer software programs or calculators?


Mary Biersack
Lab Safety and Chemical Hygiene Specialist
West Pharmaceutical Services, Inc.
P: +1 610-594-3278
530 Herman O. West Drive | Exton, PA 19341 | United States

Find West on Twitter and LinkedIn.

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