Hi. Further to my dilemma about spraying industrial coatings in a residential area I want to approach my employer about setting up a spray booth in the (stair) shop where i work.. Are there any sort of stipulations as to what kind of lights and fan that can be used. When someone says explosion proof what does that actually mean in regards to components used to build the booth.?
I know for a fact that it will need a sprinkler installed in it as it will have a ceiling.
This may also be a UV booth as it looks like I may go that route with applying polyester.
Anyway, anyone got any info to arm me with before I approach the boss...?
Thanks

It depends on where you are. Most jurisdictions require you to follow NFPA33 to get signed off and be legal. I've been through setting up new shops twice, the second time I just paid a company to do the setup. They handled all the engineering, permitting, fire suppression, inspections ect. and it was way less hassle than doing it myself. The local bylaws where my shop is located don't care if I'm 100% WB or 100% solvent, they require a legal spray booth either way.

Explosion proof means that there are no exposed electrical components, and that all wiring is in proper boxes and pipe that it will withstand an explosion inside the pipe and boxes. The flame path will not exit the wiring runs and create an explosion outside the containment fixtures. Usually you can limit any issue with switches if you have them located more than 4' from any opening in the spray booth. You can also reduce some cost if the fan motors are not in the air path. That means a belt driven fan. I designed explosion proof wiring systems for turbine natural gas compressors in my first career. Open face spray booths will not work. Talk to your insurance agent and fire marshall.

Thanks. It seems quite the task to actually do this and do it right. There is talk of setting up an open faced canopy style booth to get this off the ground quickly. The items being painted are not large. Open faced will not work? If there's enough air flow it should pull almost all the vapors out?

An open faced booth would be fine, you just have to make sure you are replacing the air sufficiently in the area you are drawing it from.

I had the local fire inspector pick out a booth, exhaust system, and dry chem fire suppressant system so to be sure the inspection was a slam dunk. Worked like a charm. I went dry chem because tying into the sprinkler system was going to be too much of a hassle in my case.

Open face won't work with explosion proof, and it may not be sufficient for your insurance agent and fire marshall.

Rich, I've got an open face booth with fire suppression in a 1600 sqft shop dedicated to finishing that's fully legal. It gets inspected every six months and getting insurance is no problem. I spray everything from WB, post cats, primarily solvent 2k poly and occasionally polyester. You just need to make sure you follow NFPA33 and they're fine with it.

Lots of good advice here. Like mentioned you need to follow the fire codes, local bylaws and regulations provided by your insurance provider.

I would say in the woodworking industry open faced booths are the most common. You will also need a make up air unit to match the cfm of your booth to replace the air that your spray booth exhausts. It is against code to put your building into a negative pressure as it then draws air in through the vents of your heating systems and can cause a deadly atmosphere of carbon monoxide in your building.

Yes great info indeed.
So the spray room/booth has been given a no.. too much modification to the building etc. Came to an amicable solution of using a man door. I've built a wedge shaped open faced booth on wheels that basically pushes into the doorway and has a good seal all around. It's about 40" deep and 48" wide at the front. It has a 20" 3300cfm at the back. Haven't actually used it yet but it pulls a lot of air and I bet it'll take all the vapors out. Explosion proof, not really but I don't think there's much else I can do. Being non permanent and being able to move has made the boss happy.
The shop is huge and the dust system pulls half a million cfm so that will need shut off as it'll probably pull air in through my little spray booth!

Seems like a very short term idea.
When OSHA or fire marshal come in they will shut it down.
Setting up a spray area is not cheap nor can it be done half way.
Check with your insurance co. Too

You say the dust collection pulls a 1/2 million cfm and the shop is large. I would assume with that much dust collection you would have a lot of equipment. I would guess with the building and equipment the owner has millions invested.

So as I scratch my head in awe, I will try to be kind and just ask the question, why?

When I ask why, I am referring to this extremely Mickey Mouse setup for a spray area. If you are lucky you will end up with no employee’s hurt or killed, however it is only a matter of time before you have an explosion or a fire and when the shop burns to the ground, the insurance company will likely say, so sad, too bad and the owner will be out millions.

If you are running a shop that big, get a professionally installed spray booth with make up air and a fire suppression system.

The shop are very interested in helping me succeed, and I'm exceptionally grateful.
This will hopefully be short term.
Ultimately this could be a whole other division if it takes off. Gotta start somewhere, right?

Make do with what you got until you make it is a reasonable thing to do in business overall.

It's not a reasonable thing to do with people's safety, ever.
It doesn't matter what you get in the end for it.

If you can't do it right on safety, don't do it.
Anything else is just incredibly selfish.

Correct. will pack it up. call it a day. lights out.