Different Fresh Air Allowances Per Person

"A habitable room requires one or more ventilation openings, the total area of which must not be less than 1/20 th of the floor area of the room, and some part of the opening must be more than 1.7 meters above floor level.

When ventilation is by mechanical means, one air change per hour must be provided to habitable rooms and three air changes per hour to bathrooms and kitchens."

Fresh air allowance is based on an 8 liter/s per person minimum and increased according to room type and usage allowing for fumes and smoke and other contaminates that may be produced in the normal course of room usage at max capacity design....These guidelines are designed to insure O² and CO² levels are maintained at healthy levels...

http://www.arca53.dsl.pipex.com/index_files/vent2.htm

http://www.arca53.dsl.pipex.com/index_files/vent7.htm

There's nothing wrong with your answer, SolarEagle, but the OP had given no indication as to the situation. Diving, mining, Space Sation. It could be anything. Regs for housing and buildings in general are well documented. Without further info, the OP may as well ask 'how long should string be ?'.

i am doing a hvac commissioning course and that is how the question is worded, dont think it is asking for actual values just where and why different fa/p/p is used and for what reason

I could take a reasoned guess at ' fa/p/p', but why not ask the people running this course. If they leave you hanging, with no sources to use, is it worth it and does it have credibility. Scope CR4 and you will find a recent blog that gives an extensive link to terminology. By following that, you may find an answer. Sometimes, banging your head on the wall is part of the learning process. Do some searching - If you come back with a more detailed question, and hopefully an actual problem, people may help. Sorry to sound harsh, but that's the way it is. If you struggle to understand a particular point and later come back asking for help, people will (in my obsevation) be helpful.

That sounds very pompous, but I am trying to save you grief.

Ahh so, young Grasshopper. More homework questions!

Learn by your own endeavours, the results will be more rewarding.

When other people think its funny to fart when there's a captive audience.... Like in an elevator.

Put that in your essay.

Here's all you need to know: How to Search the Internet Effectively
Oh, and if you are going to continue to ask strangers to do your work for you, be sure you get a job where you can always carry your laptop with you.
The string is too short.

phoenix911 got it right. The more stink you have, the more fresh air you'll need.

Would you need a better exchange of air in a Paint spraying booth or a gym locker? Hmmmmm, let me think. No farting please! Different reasons are aplenty.