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huangkai81
05-22-2005, 12:07 PM
hi fellows
im a student from china. in china wo use 30 m3/p.
so how you decide?
thank you first.

pstu
05-22-2005, 05:49 PM
If you can look up ASHRAE 6.2 that will help explain things. Let me try to translate to English units which are more familiar to many: 30 cubic meters per person is about 880 cubic feet/person unless I made an error.

I must ask, over what period of time? The numbers I see are usually in units of cubic feet per minute (CFM). If your time period is one hour, I think that translates to 14.7 CFM.

Regards -- P.Student

[Edited by perpetual_student on 05-22-2005 at 05:52 PM]

huangkai81
05-22-2005, 11:34 PM
im sorry.ive forgotten the time period. its an hour.
im looking up ASHRAE 6.2.
any other suggestions?

pstu
05-23-2005, 03:00 PM
I am rusty on what I used to know and was *never* an expert, just an amateur trying to figure out what is best for his home. But as I recall, your number is very close to what ASHRAE recommends per person.

There is also a recommendation of approximately 0.35 ACH (air changes per hour), which is dependent on the volume of the building and not on the number of people. Again I am quoting from memory and could be off. In the case of many houses, this number is larger and what ASHRAE recommends.

If any other pro cares to elaborate on this, we could both learn from that.

Best wishes -- P.Student

portege
05-24-2005, 01:17 PM
if you want to decide fresh air requirement, please detail what kind of facility/offices you will use the fresh air.

if it's use for cleanroom, you can add room pressure (room volume x 1.2mmAq) + exhaust air requirement of production equipment.

if you want to know the fresh air requirement of ordinary offices just multiply 34cmh/person or you can increase it if there is heavy smoker in your office. (also you have to add some local exhaust requirement)

huangkai81
05-25-2005, 12:01 AM
it is a good suggestion.
if i want to get some details or recommends about all kinds of facility/offices,where i can get just for free?

now there are other question emerging. the place that the house/office located in have the different air quality.in china we often debate about it in chinese bbs. the recommend's data looks like......
is it not necessay to think about it?

ofcouse i think ive got what i want,thanks for support me as a comer during these days.

teddy bear
06-02-2005, 11:13 AM
What part of China are you from? Any fresh air ventilation or dehumidification used?

huangkai81
06-08-2005, 04:59 AM
i'm from the province of jiangsu.