Search results for query: *

I think that it is NFPA-90A that you want ..... (but I might be wrong ....) and there is a requirement for shutdown of all systems above a certain flowrate (15,000 CFM I think) into any single smoke zone AND which are in a space covered by the reqmts of NFPA-90A (ie NFPA-90A doesn't necessarily...

Yes, I'd have to agree with the pressure relief aspect - in 90% of the systems that have problems when we look at them (either during construction or during annual performance inspections), we find that insufficient relief is the main source of difficulty.

We (in Australia) use variable speed drives (ok, frequency inverters to some of you) for ALL new stair pressurisation systems. Pressure sensor in stair well is your point of control, fan speeds up or slows down to try to maintan pressure, regardless of doors opening or closing ...

Smoking is prohibitted in the workplace here .... so you cannot design a system supposedly for smokers or else the cancer council people will take you to court and sue you so badly that you'll never work again ....

We designed a seawater primary/secondary system here in Sydney and found that the mussel spores got into the system and as they grew they got to "learn" the pattern of chemical dosing (which was supposed to get rid of them) and they would "close up" as that time approached, and open up again...

Did you ever get an answer to this query? If no, then tell us where in the world you are so that someone local can be of assistance ...

And here in Australia, we have bush damper ..... which is a traditional bread ...... Nothing to do with engineering but, hey, knowledge is knowledge!!

The need for lift shaft pressurisation is NOT directly from the simple fact that AS.1668 mentions it (after all, 1668 mentions shutdown system - chapter 6 - but BCA part E2.2 references chapters 5 and 7 but skips 6). However, there is a clause later in BCA (can't remember the number) where it...

Billy's comments and all others notwithstanding ...... The perf foil goes OVER the melinex. The purpose of the foil is to keep the insulation in place - it is merely a "retainer". The retainer, if you'll forgive the label, is metal when you anticipate that the retainer will be subjected to...

I'm all for simplifying things when it comes to clients ..... remember, they see things from a different perspective so, much and all as that may annoy us engineers, it's something we need to always bear in mind. So, in my view, it is not a matter of what the system was sized for (because the...

Thanks for that, mate. My problem (which has since been resolved) was more one of legal/administrative detail rather than one of science and common sense. I finally got a letter from our standards body here confirming that their codes assumed that carpark exhaust discharges are "not obnoxious"...

Anthony - yes, it has been a while. The guy to speak to at Standards is Boris Krastev - I'll dig out his direct line but you can also drop him a mail - in many respects, the email is the way to go because he can then simply farm your query out to the various members of the appropriate...

Humidity needs to be controlled otherwise either (a) corks dry out and air gets into the wine, or (b) corks get too mouldy and mould gets into the wine. Temperature stability is much more important than ABSOLUTE temperature. It can be hot or cold (relatively speaking) as long as it doesn't...

Well, I know now that you guys are all engineers in the truest sense that you never seemed to get bored of the "puzzle" nor angered by the criticims of the other writers. Me, I got bored of the tech stuff (mustn't be a real engineer, me) but enjoyed the human interaction!!! (anyone...

have a safe trip, billyQ !!!!! PaulieK

Hire a specialist ........ or in your arrgt, is it easier to measure the air going IN rather than the air coming out???

need to be careful with stratification ...... RA temp may be a few degress higher than occupied space if RA is collected at high level in a very tall space ..... play around with offset to "compensate/falsify" the sensor output..... Other answer is to put RA sensor beside the seat...

What bothers me is how you managed to lease out space to a tenant and have him belive that the a/c system could do more than it actaully could handle!!! Either the tenant was duped by you or he's trying to dupe you!! I agree that you must treat it like a new project, come up with a fresh...

Make sure you look into the control sequencing - ie what happens to your OA supply temperature when one (or more) of your units is in de-ice mode ......

ChasB, Thanks for that piece of code - I'll apply it to a few situations here and see what it throws up. Anthony, I too have come over to the dark side - my days at Arups and Lincolne Scott and a few minor players in between erased all respect that I used to have for the quality and ethics of...