REQUIRED TOILET ACH in AIA GUIDELINES
REQUIRED TOILET ACH in AIA GUIDELINES
(OP)
The AIA/FGI Guidelines Ventilation table lists toilet rooms in hospitals as requiring 10 ACH at negative pressure. Is this for general toilets only? Does it also apply to toilet rooms inside negative pressure isolation rooms? If not, is there no/any ACH requirement for toilets inside negative pressure isolation rooms?
Thanks for any quick guidance you can offer. I am having a discussion with a colleague and his client and we are interpreting the Guidelines differently.
Thanks for any quick guidance you can offer. I am having a discussion with a colleague and his client and we are interpreting the Guidelines differently.





RE: REQUIRED TOILET ACH in AIA GUIDELINES
For AII rooms with toilets, refer to ASHRAE 170-2008, addendum f.
RE: REQUIRED TOILET ACH in AIA GUIDELINES
If I may ask another questions as well; does the AIA/FGI state somewhere that the table line item for toilet rooms is only referring to general toilet rooms? I couldn't find that distinction.
Thank you for any further clarification you are able to provide.
RE: REQUIRED TOILET ACH in AIA GUIDELINES
Plus ASHRAE 170-2008 7.2.1 says all air from AII rooms, associated anterooms, and associated toilet rooms shall be discharged directly to the outdoors. From this, we can conclude that the anterooms and toilet rooms require local exhaust in each room.
RE: REQUIRED TOILET ACH in AIA GUIDELINES
To summarize, do AII toilet rooms have a requirement for a certain number of ACH or do they not. I say they do, because I have not seen anything in the standards or codes that differentiates AII Toilet Rooms from General Toilet Rooms in respect to EITHER ACH or pressure to an adjacent area.
Thank you to anyone who has or can contribute to this discussion.
RE: REQUIRED TOILET ACH in AIA GUIDELINES
We've used 10 AC/HR here in PA with no objections whatsoever from the Department of Health.
You stated your colleague or his client had a different interpretation. I curious as to what that interpretation was and what it was based on.
Regards.
RE: REQUIRED TOILET ACH in AIA GUIDELINES
Our company assists hospitals in verifying proper ventilation and pressure relationships for a variety of areas, one being AII rooms. On a recent visit, my colleague had reported to the engineering dept that a couple of the AII rooms were not meeting the 10 ach requirement for the toilet rooms. The engineering dept took issue with this and apparently an architect they use gave them that information. They stated that 10 ACH weren't required for AII toilet rooms. That is what started the discussion. I haven't been presented with any information to support their assertion. I have contacted FGI and ASHRAE for an interpretation, but have not heard back.
My own viewpoint is that if there was an exception for toilet rooms in AII rooms in respect to ACH, it would have been mentioned in the addendum that urgross pointed out above or in the various guidelines and/or codes. I can't find those exceptions. Therefore, I don't know why I would treat AII toilet rooms any differently.
RE: REQUIRED TOILET ACH in AIA GUIDELINES
If the wording in the code can possibly be interpreted in more than one way, don't debate. Ask. There's an authority having jurisdiction who will be approving or rejecting the decision. The ones I have dealt with were happy to resolve issues before they were found on drawings or in the field.
Call them up!
Best to you,
Goober Dave
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RE: REQUIRED TOILET ACH in AIA GUIDELINES
RE: REQUIRED TOILET ACH in AIA GUIDELINES
Best of luck resolving it!
Best to you,
Goober Dave
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RE: REQUIRED TOILET ACH in AIA GUIDELINES
isolation room is negative to other part of the hospital, toilet room in isolation area should be negative to surounding area which is the isolation room i this case,
also I belife Georgia code like other codes request to provide exhaust fan in each washroom, that men you have to exhaust. but about the number of ACH if nobody defined it officialy then use engineering practis beside referances such as ASHRAE or other as the codes say usual
RE: REQUIRED TOILET ACH in AIA GUIDELINES
RE: REQUIRED TOILET ACH in AIA GUIDELINES
ORIGINAL QUESTION BY WAY OF FGI WEBSITE FORM
The AIA ventilation table lists toilets as requiring 10 ACH at negative pressure. Is this for general toilets only? Does it also apply to toilets inside negative pressure isolation rooms? If not, is there no/any ACH requirement for toilets inside negative pressure isolation rooms?
If there is a requirement for ACH (10 or otherwise) inside negative pressure isolation rooms, is the ACH computed by the amount of exhaust in the toilet room? Does that change depending on whether there is a supply included inside the toilet?
Thanks for any quick guidance you can offer. I am having a discussion with a colleague and his client and we are interpreting the Guidelines differently.
ANSWER FROM FGI
Mr. Silverman:
I have forwarded your request to the chairman of ASHRAE 170 for response. I would anticipate a response from him shortly.
I have also included addenda "f" which addresses toilet and anterooms that are a part of the airborne infection isolation room. When it states directly opens onto an AIIR it does not mean without a door. It means without opening onto any other spaces.
Douglas S. Erickson, FASHE, CHFM, HFDP
Chair
Health Guidelines Revision Committee
ANSWER FROM ASHRAE 170 CHAIRMAN
I offer the following unofficial interpretation of Standard 170.
Questions are:
Q1. The AIA ventilation table lists toilets as requiring 10 ACH at negative pressure. Is this for general toilets only?
Response 1.
Q2. Does it also apply to toilets inside negative pressure isolation rooms?
Response 2.
Q3. If there is a requirement for ACH (10 or otherwise) inside negative pressure isolation rooms, is the ACH computed by the amount of exhaust in the toilet room?
Response 3.
Please note: the 10 ACH for the toilet will not be the same volume of air as 10 ACH in the AII room unless the toilet is the same size as the AII room.
My FOLLOW-UP
Thank you very much for your assistance. I have some follow up questions.
Q1. How does one get an official interpretation of a standard?
Q2. I understand exhaust from the Toilet Room inside an AII room can be used to achieve the required total of 12 ACH for the Main Room. Is my understanding correct? If so,
In the case of an AII room with a Toilet Room, should the total ACH for the Main Room be computed by combining the exhaust for both the Main Room and Toilet Room and dividing it by the volume of the Main Room and the volume of the Toilet Room?
ACH = 60(MRcfm + TRcfm) / MRvol + TRvol
Or, should the total ACH for the Main Room be computed by combining the exhaust for both the Main Room and Toilet Room and dividing it by the volume of the Main Room only?
ACH = 60(MRcfm + TRcfm) / MRvol
Or, is there yet another way it should be computed?
RE: REQUIRED TOILET ACH in AIA GUIDELINES
Best to you,
Goober Dave
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RE: REQUIRED TOILET ACH in AIA GUIDELINES
RE: REQUIRED TOILET ACH in AIA GUIDELINES
Grandfathering is not a straight forward issue and in respect to life safety should be avoided in my opinion. I know, for instance, that the NFPA does not consider grandfathering a legitimate practice when it comes to medical gas systems. I can't definitively speak to how they or others would view it on additional matters though.
In respect to my original question, however, the rooms are not grandfathered and I'm not sure if that is even possible. Going back as far as the 1987 Guidelines, Toilet Rooms (and "Bathrooms") required 10 ACH.
The whole question centers around whether or not the AIA/FGI Guideline's line item for "Toilet Room" refers to ONLY general Toilet Rooms like those found in corridors and departments or to ALL Toilet Rooms including ones found in AII Rooms.
My position has been that it refers to ALL Toilet Rooms, not just GENERAL Toilet Rooms.
RE: REQUIRED TOILET ACH in AIA GUIDELINES
RE: REQUIRED TOILET ACH in AIA GUIDELINES
RE: REQUIRED TOILET ACH in AIA GUIDELINES
Thank you for posting the response.