about the paint booth exhaust
about the paint booth exhaust
(OP)
How to decide the exhaust air flow for a paint booth hood? What kind of exhaust fan is typically used? The ASHRAE mentions the ACGIH. What's that?
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS Come Join Us!Are you an
Engineering professional? Join Eng-Tips Forums!
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail. Posting GuidelinesJobs |
about the paint booth exhaust
|
RE: about the paint booth exhaust
RE: about the paint booth exhaust
Paint booth ventilation is such a common application that the problem is addressed by a number of Ventilation textbooks. I think the ASHAE manual does not go into it because it is not the core subject of air conditioning and refrigeration.
There are a number of points to watch with paint booths
1 - if the air velocity is too high the wet paint will start to run and disturb the finish
2 - the air must be filtered - otherwise dust will be attracted to the wet paint
3 - the exhaust will carry droplets of paint. This tends to build up on the inside of the ducts, and on the surface of the fan blades
4 - you cannot discharge paint into the atmosphere - so you have to make a plan to clean up the discharge. Often spray chambers are used to trap the paint droplets
5 - a small hood may work with a kitchen propeller fan, but for a larger volume you will need a centrifugal fan. The pressure drops involved will also dictate this. Talk to a fan Vendor for a recommendation
6 - it is important that the air distribution is as even as practical - to prevent fast moving streams developping in the painting space
RE: about the paint booth exhaust
OSHA regs protect the worker inside the booth; typically require some minimum velocity of 60-100 linear feet per minute, depending on application method.
EPA regs are to collect the paint overspray on the filters, filtration efficiency depending on the hazard & volume of paint applied. Minimum flow rates & changing filters is required when ΔP across filter reaches 1.5" water column (or similar). So, allow a deep plenum for high capacity bag filters to minimize changing.
OSHA & Fire Code may require internal sprinklers in both booth & plenum, plus approved booth lighting, for flammables.
http://www.chemcomfg.com/overspray.htm
Chapter 9 in DOD Handbook INDUSTRIAL VENTILATION:
http://www.wbdg.org/ccb/DOD/UFC/ufc_3_410_04n.pdf
RE: about the paint booth exhaust
Their "Industrial Ventilation" handbook has specific paint booth requirements and design parameters.
http://www.acgih.org/home.htm
RE: about the paint booth exhaust
RE: about the paint booth exhaust
RE: about the paint booth exhaust
RE: about the paint booth exhaust
RE: about the paint booth exhaust
RE: about the paint booth exhaust
B.E.