Self Contained In Pharma Applications

[munesh]

One of my clients require airconditioning for the pharma Clean room applications. His static need is 50mm Aqua. I got a proposal from one of the sources for the self contained AC for the same requirement. This equipment is having good static. So can I use SC for this kind of applications?
BTW what is the important criteria for the clean room application static only or anything more/
Is self contained a solution if not why.

[munesh]

Please help if anyone is having any idea on the same?

[munesh]

No Idea!!! Okie

[The Viking]

OK,
As nobody else picked up the ball...


On the clean rooms I worked on (admittingly, that's about 9) there is a standard recirculating ducted unit, depending on the loads this could be any bog standard dx unit or an AHU. To the return air is then ducted a "make-up" fresh air fan and from the room itself is a duct with a VCD and a NRD fitted.

Before the fresh air fan and before the coil would be standard filters then on the supply side (after the unit) there would be a box housing the high grade filters.

Based on the above, you should be able to use any ducted unit as the "actual" static pressure for the unit to overcome would be less than on an identical installation in a "normal" environment.

Good luck.

[TRASH101]

Just to pick up a bit more:

Cheapest way is to use complete recirculative air so the return air path is not a "clean issue" unless you duct it out of the room where contaminants may ingress due to the a/c fan suction pressure versus ambient static pressures.
But the supply side may always be an issue if you need really low particle counts as mechanical shedding within the a/c could affect this.

There fore I suggest you scavenge return air from the main system (so std controls will have a fighting chance) mount the a/c out of the clean area duct it back in via HEPA terminals (find a a/c manufacturer that offer a high static fan and then design your vol per HEPA aound the fan)

Even better add DX and/or Heating to the existing vent sytem but dont forget pharma applications are usually RH critcal as well.

[abbasi]

actually i have wotrked on scores of pharma units.
Let me tell you that there are different filteration requirements of different process rooms in pharma company.
some people design it with terminal hepa filters in duct that would normally increase Total static by 1.5" WC. also bag filters also increase the static. so static varies with filter sections/filters.
Also pharma airconditioning is very tough as you have to maintain RH of 35-45 in certain areas.
for this what we did was to use 3 stage DX coils with 3 stage electric heaters and humidistat as controller.

Basically how i designed was to

take 15% fresh air and 85% return air, take its mixture plot it on psychrometric chart. cool it to 40 degree F and reheat to place where you reach required RH
BTW we had a lot of success

[Greengrocer]

By it's very nature a clean room must be clean. This is why many AHU's have HEPA's on the supply (belt particles fron fan drive) and return air side. Rooms need to have positive pressure to prevent ingress.
Many AHU manufactueres make "clean concept" type units especillaly for this type of application. Clean concept generally means the inside of the AHU is smooth and devoid of any duct / dirt traps so it can be kept clean. High sensible load and low RH's also mean close control so once again a std AHU is not really going to do the job.

[Sridhar1312]

Clean room of what class, if you are looking at class 100000 then it is possible with standard package unit may be with additional fansection or change pully to increase static.If you are looking at class 10000 it is better to go for Air handling unit with higher static to take the filters and higher air change required in the room.