Surgical Suite 3

[fayazdin1]

Hello friends,
Need your input :
Surgical suite consists of 6 operating rooms and a support area in the middle (nursing station)
Operating rooms are pressurized and have proper ventilation.

AIA 2006 and ASHRAE calls for 6 air-changes with 2 outside air changes for support area

In my case, infiltration into the support area from operating rooms is more than than the
airflow i need for support area ventilation.

Q: Do I still need to provide ventilation directly from AHU into support area OR
I can rely on airflow from operating rooms into support area?

Thanks
Fayaz

 

[chicopee]

I would definitely not reuse air that has circulated in the operating rooms to the support area, if I understand your last question.

 

[fayazdin1]

Chicopee ......... There are 6 OTs around nursing station. Each OT is pressurized to 20% with respect to surroundings.
All the excess air leaks into the nursing station.

Total air from OTs is more than what I need for Nursing station ventilation.
So, do I have to add more air for nursing station or I can take credit of the OT air infiltration into the nursing station?

 

[EnergyProfessional]

I assume since the OT are pressurized their air is not considered contaminated and can get used in other rooms. Otherwise it would have to get exhausted and be negative.

 

[urgross]

The air will have to be accounted for at TAB, so I would recommend you consider it now. Is the 20% differential volume between the OR and exterior needed to reach an assumed differential pressure? If so, then will pulling 6 ACH from the clean core without additional supply allow that perimeter differential pressure to be maintained? If the overall dP can be maintained, then adding more supply is a waste of energy. If not sure, a supply could be added for TAB purposes and set to match dP requirements. It might also be useful if taking down any of the OR's in the future for repair or upgrade.

 

[weaver101]

May be a perimeter coridor to exhaust, instead of the nursing area, from surgery suits. Individual supply air and exhaust air for the nursing area is more reliable way.

 

[EnergyProfessional]

the OT also may be ventilated based on schedule/occupancy, so you can't necessarily rely on those ventilating other rooms

 

[Drazen]

sound like case where you would want filtering of transfer air to make all that purposeful. active carbon would be a must.

and yes, you would still need direct outdoor air to satisfy your 2 ach.

 

[MintJulep]

Exhaust air from any space is not "fresh air" and thus cannot count towards an air charge for another space.

 

[SAK9]

Go with Urgross's suggestion and adjust as required during the TAB.Do you have have variable exhaust out of the Nurse station to account for some theares being offline?

 

[Drazen]

as far as i could comprehend, transfer to nursing room primarily serves to relieve pressure from operating rooms. i.e. allowed maintained pressure differential.

with oa requirements for nursing room fixed, and with varying transfer air, it seems that best solution would be to have pressure-regulated exhaust fan in nursing room.

heat recovery is seemingly not easily attainable. if air from operating room goes to nursing room, only nursing room oa portion can be drawn through heat recovery unit, but that is obviously small portion of total air demands.

hydronic based heat recovery is possible, but would be quite complex and expensive, with exchangers at each op.r. supply, and large exchanger on common nursing room exhaust.

 

[chicopee]

If you are intent on reusing air from operating rooms, you may want to research ozone genrators that will kill germs, bacterian, viruses, mildew.

 

[317069]

How can you make sure that the infiltrated air from operation rooms to support area contain the right amount of the fresh air that is required for support area.
are operation room over ventilated? we mix between air change number( 5, 10 , 20 or more depend the application) and fresh air required as cfm/person or cfm/area.

 

[tys90]

Even if it was allowed, I wouldn't do it. That's just asking for trouble and the amount of OA to the nursing area pales in comparison to the surgery suites.

 

[ChasBean1]

The nurse stations are in corridors and have a ventilation requirement of 0.05 cfm/ft2 (by US Code anyway), which is barely a puff. The excess air from ORs is more than enough to satisfy your corridor ventilation requirements.