ASHRAE 110/2005 and Lab Air Changes

[BronYrAur]

Does anyone know if ASHRAE 110/2005 covers recommended air changes in a lab. Before I buy it, I would like to know if it will answer that question. If not, does anyone know another reference? My specific job is with the USDA in Wisconsin, and I am trying to find out if they have their own specifications. If not, how should I select an air change rate? The types of labs vary from chemical to biological to radiological.

 

[imok2]

• Cleanroom recirculation air systems
Cleanrooms of class 1000 and cleaner have air change rates of 600 to 900 per hour. Large amounts of energy are necessary to transport these huge quantities of cleanroom air and remove fan heat. Recirculation air systems for cleanroom designs can maximize energy savings by reducing both the unidirectional air-flow rate and the pressure drop in the air recirculation loop. Significant energy savings are also possible when high-efficiency components are used for circulating these large quantities of air. [Naughton, "HVAC Systems … Part 1, 1990]
In cleanrooms, air flow is a generally fixed parameter based on the air velocity desired. Required fan horsepower can be reduced by one-third if the clean room is provided with a mixed HEPA filter air velocity and only the product and the production equipment are covered with 90 fpm (0.457 m/s) air flow while the remainder of the cleanroom operates at a lower velocity of 60 fpm (0.305 m/s). [Naughton, "HVAC Systems … Part 1, 1990]
Major energy savings can be achieved by lowering system static pressure and improving fan efficiency. The energy required to overcome the system static pressure rises at a cubed rate, thus increasing energy requirements exponentially. [Ciborowski and Pluemer, 1991]
For more :

http://ateam.lbl.gov/Design-Guide/DGHtm/airsystems.htm

 

[Commish]

ASHRAE 110 is a Method of Test for Fume Hoods and does not recommend Air Change Rates for Labs.

OSHA regulations call for a minimum of 4 air changes per hour.

Some labs need more than 4 ACH if the Fume Hood requires more air. Work activities may also increase air supply design quantities.

It is important to have the Safety Rep for the team participate in the ACH discussion. Industrial Hygenists will also review other sources of exposure for workers in the lab.

 

[AbbyNormal]

The couple labs I did always wanted to be slightly pressurized. So maybe that would rule on how much fresh air you need.

The cleanrooms are always pressurized, the high air change always seems to be to get the air through the filters so many times.

Take the "V" out of HVAC and you are left with a HAC(k) job.