Positive Pressurization Required

[AnakinSkywalker]

I am a newly graduated engineer, and I required some guidance on the positive pressurization of a building/room is required to minimize the induction of aspergillus spores into the air of a Compost Plant lunchroom. I have read some of the other threads on static pressure which helps, but I need help books to reference, equations to follow etc. Any guidance on this problem is much appreciated. The only information I have is that there will be 30 people in the room at once (max),the room is 22 x 16, and positive pressure is required.

 

[quark]

Creating positive pressure may not be the only solution in your case. Proper filtration system (presumably HEPA) and periodic fumigation with formaldehyde are general practices.

 

[wegmeister]

to maintain a given positive pressure
door(s) closed proceed as follows : calculate total squarefeet of crack ,figure out
how much air you have to force across the crack to create a pressure drop of say 0.2" W.G.
Normally,300 cfm will be plenty for 1 door.Use a
centrifugal fan and HEPA filter to pressurize.

A more sophisticated design would involve a Magnahelic
pressure gauge(ck=heck their web site!!)generating
a 4 to 20 mA signal proportional to the differential
pressure between the room and the adjacent plant
area.The signal goes to a variable speed drive of
a centrifugal fan with a max capacity of about
1000 cfm.The fan draws HEPA clean air for an
uncontaminated area or from outside c/w heat/cool as required.

 

[VEEKRISH]

Anakinskywalker,
If you've read the various threads on this subject, and are a beginer, then let's make it very simple -

Firstly, is the space being conditioned, or merely being ventilated?

In any case, local requirements will mandate a minimum ventilation rate (air changes per hour / cfm per person etc).
Based on this I wouyld suggest a system which will bring in the minimum amount of air quantity required (fresh air or conditioned as the case may be). Just ensure that you exhaust out about five to ten percent less than this figure. This will ensure that the area is positively pressuirized.
Having said that, you must ensure the following -
Minimum leakages through cracks, openings etc.
Filteration levels and fumigation needs (as quark has rightly mentioned)must be checked to meet local standards and needs.

 

[209larry]

The requirements are air locked doors (two door entry) air duct damper and manometer. Design will be similar to centralized HVAC system.

But the question is how would you kill aspergillus spores in fresh air make-up, can it be killed by ozone or UV?

209larry