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Covering paint spray booth sprinkler heads, tested?

Covering paint spray booth sprinkler heads, tested?

(OP)
Does anyone know of a test that measured the response time of a covered or 'bagged' sprinklerhead in paint booths? I found a 1993 test done in sweden and it was a very comprehensive test that showed the response time to be 2 to 5 times longer than without covering. Even painted heads had a close to normal response time. The paper bags were the worst with up to 5 minutes response time, and the cellophane was still bad with 2 minutes. The uncovered heads went off in 42 seconds.
This next link demonstrates that a sprinkler head will respond in under a minute if uncovered, then they demonstrate what a fire will look like at 2 minutes.
https://m.youtube.com/watch?v=VEXav_iBEZ8

If a covered sprinkler head takes longer than the designed 1 minute or less, then covering them is not a good solution and is very dangerous.



file:///C:/Users/Tom/Downloads/Response_Characteristics_of_Glass_Bulb_Mounted_Sprinkler_Heads_Mounted_In_A_Paint_Spray_Booth.pdf

RE: Covering paint spray booth sprinkler heads, tested?

Are you mixing monkies and elephants?


Where did you get the "" If a covered sprinkler head takes longer than the designed 1 minute or less"""??

RE: Covering paint spray booth sprinkler heads, tested?

Why the question??

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
Im looking for tests done in the United States. In the NFPA 33 2016 they call for heads to be protected from overspray, either by location or covering. Then they say you shall be permitted to cover with cellophane of a certain thickness or paper that is thin. For them to say the thickness of cellophane can be no more than "0.08 mm (0.003 in.)" sounds like other thicknesses failed and they settled on this thickness. Then the paper just being described as 'thin' sounds like it was never measured.

9.4.7 Sprinklers shall be protected against overspray residue, either by location or covering, so that they will operate quickly in event of fire. 9.4.7.1 Sprinklers shall be permitted to be covered only by cellophane bags having a thickness of 0.08 mm (0.003 in.) or less or by thin paper bags. These coverings shall be replaced frequently so that heavy deposits of residue do not accumulate. 9.4.7.2 Sprinklers that have been painted or coated by overspray or residues shall be replaced with new sprinklers.

The reason Im looking for this is to argue that by placing the heads where they will not get paint overspray that we have satisfied code, and covering the heads is not necessary.

Covering the heads in the swedish tests proved to extend the response time of the heads to 2 minutes for cellophane and up to 5 minutes for paper. They tested the air temperature in the bags during the tests and found the air in the bags insulated the head and kept it cool so instead of popping at 155 degrees they had to wait till the bag melted at 350 degrees or the paper burned at 450 degrees. Waiting till that temperature the fire is flashed over and much larger than it needs to be.

They tested with paint on the heads also, in three different thicknesses. The thickest being 1/64 of an inch. One inch is 1000ml. A 64th of that is 15.62 ml. An average car has 4 to 5 mls thickness of total paint and primer. To get 5 mls painters apply 2 full wet coats of primer, 2 full wet coats of color and then 2 full wet coats of clear paint on average. In order to get 15.62 mls, they would have to spray 19 wet coats on the sprinkler head. This doesnt describe 'overspray', this describes painting it over three times the same as a car. And they do define overspray in the nfpa33.

section A.4.7 of the nfpa 33 2016 also talks about location of heads.
Automatic sprinklers in spray areas, including the interior of spray booths and exhaust ducts, should be wet pipe, preaction, or deluge system so that water can be placed on the fire in the shortest possible time. Automatic sprinklers in spray booths and exhaust ducts should be of the lowest practical temperature rating. The delay in application of water with ordinary dry pipe sprinklers can permit a fire to spread so rapidly that final extinguishment is difficult without extensive resulting damage. The location of the sprinklers inside spray booths should be selected with care to avoid heads being placed in the direct path of spray and yet afford protection for the entire booth interior. When sprinklers are in the direct path of spray, even one day's operation can result in deposits on the sprinklers that insulate the fusible link or choke open head orifices to the extent that sprinklers cannot operate efficiently.

The heads in tests done on you tube appear to take 1 minute or less. our sprinkler heads are designated for 155 degrees. Also on firesafesystems.com/faqs they said, " In reality, each sprinkler head has its own heat sensor and each sprinkler will operate only when the temperature reaches between 155 and 165°F. A fire in the garage for example, will activate only the sprinkler(s) in the garage.
FAQs | Fire Safe Systems
firesafesystems.com/faqs/"






RE: Covering paint spray booth sprinkler heads, tested?

(OP)
In the NFPA33 2016 they talk about quick response in many areas. But then to ask for covering the heads it seems they are defeating that purpose. I would think the sprinklerhead companies would have designed a cover for paint booth if it was a problem. The bag or covering to us appears to be jerryrigging. Again if covering them was tested and longer response times were found, then the best solution is not getting paint on the head.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
I read the swedish tests back in the early 90's and removed the bags from all our paint booths and just made sure they were inspected yearly and that no paint was getting on the heads. The last edition of the nfpa 33 2016 changed some wording by adding the 'location' to the 9.4.7. We have always believed the bagging or covering part to be described and allowed as a last resort if you are sloppy and getting paint on your heads. These booths are 8 feet tall and the heads are on the ceiling. No paint can get on the heads unless you intentionally spray them. The booths remove any overspray right away and put the dried dust overspray in the filters. Vapor doesnt even rise to the ceiling. If someone was to allow paint vapor and wet spray to go near the ceiling then the booth fan would probably have to be shut off, it would be impossible if the fans were running. Some of our booths wont let you have air to spray if the fan is off. Older booths do not have this failsafe. We usually cover the heads when the booth itself is painted yearly with water based paint. Then the covers are removed for daily use.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
The tests we have done on our own on cellophane show that the cellophane melts and balls up and could possibly block or redirect the water flow. And paper takes way too long and also hangs over the head after the water starts. We would rather let our heads operate the way they were intented to.

RE: Covering paint spray booth sprinkler heads, tested?

You overthinking this, I have inspected 1000's of paint booths, if the heads are not protected they will have paint on them and will not operate properly. I tell my clients to change the paper bag when you change the filter, the booth is down, how long does it take to replace a paper bag. Remember the sprinkler location is based on the sq.ft. of the booth and max spacing of 100 sq.ft. Moving a head so it does not have paint may result in not having a sprinkler near the fire.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
You arent thinking about the persons life. The swedish tests shows response of heads that have has 4 8 or 12 layers of thick paint also. There is hardly any added time to response if paint is on the head. It isnt the time or effort of replacing the bag. Its the delay in the response time. The cellophane delays the head 2 to 3 minutes and the paper bag can delay it up to 5 minutes. The fire will flash over in 2 minutes. If a man falls and gets incapacitated and triggers a fire, an uncovered head will save his life. A covered head will kill him.

No paint gets on the heads these days. The EPA now has bodyshops teach proper gun control and to shoot the paint on the car instead of in the air. The booth fan is running and the abient airflow dries the paint so rapidly now the overspray is like dust. The nfpa 33 says the protection from overspray can be from location or covering.


https://www.youtube.com/watch?v=VEXav_iBEZ8&t=...

file:///C:/Users/Tom/Downloads/Response_Characteristics_of_Glass_Bulb_Mounted_Sprinkler_Heads_Mounted_In_A_Paint_Spray_Booth.pdf

this swedish test shows how dangerous it is to limit the head. They find that the trapped air in the bags insulate the head from responding at 155 degrees.

RE: Covering paint spray booth sprinkler heads, tested?

Codes and standards aren't designed for optimal performance but acceptable performance.

I don't believe paint booths are designed for unconscious/incapacitated persons occupying them. We should hope if this is a common problem paint booth manufacturers and code officials would address it.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
Well we have to address this. All of us are in our late 50's and early 60's. We shouldnt have to work in an unsafe place needlessly.
After 34 years we have no paint on our heads, none. So we have no risk of limiting the water flow.

RE: Covering paint spray booth sprinkler heads, tested?

Tom:

What is your goal here? If you are talking about in the US, the booths are going to be designed to NFPA standards. Anyone that does something else has a huge liability risk. If you believe the standards should be changed, then submit a proposal, with documentation to back it up, to the appropriate committee and see if you can get the standards changed.

Travis Mack
MFP Design, LLC
www.mfpdesign.com
"Follow" us at https://www.facebook.com/pages/MFP-Design-LLC/9221...

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
Ill have to do that. The booths are designed well enough, the sprinkler heads are designed well enough, the nfpa designates where the location of the heads should be, they suggest placing the heads out of the path of spray, but then the whole system gets jerryrigged by putting an unengineered cover over the critical head. My point is that the cover is not mandatory as some fire officials say. The covers are 'permitted' but the code does not say they are required.
Yesterday we conducted our own tests of cover materials. The flaw seems to be that the bag encapsulates so well that any type enclosed bag insulates the head so well that it doesnt let the sensitive part melt. The swedish tests showed the cellophane extends the melt time to 2 to 3 minutes and is at 300 to 350 degrees. The paper bag is worse, it extends to 5 minutes and finally blows apart at 400 degrees.
Our makeshift tests so far of tinsel,cellophane bags with the bottoms cut off and slits cut vertically to make a 'grass skirt' or paintbrush hairs do not insulate and the heads have melted at 155 degrees. So the protection against the paint overspray is the same, the overspray would attach itself to the hairs or plastic strips hanging down over the head but would still be pliable when the water pushes past them. There was no difference in the flow of water. Big improvement in response time. There are many youtube videos out there that demonstrate the huge difference in fire severity as time progresses. The nfpa 33 2016 stresses that first, the goal is 'operate quickly'.

9.4.7 Sprinklers shall be protected against overspray residue, either by location or covering, so that they will operate quickly in event of fire.

The overspray is really not as big a detriment as this all seems. The head with the overspray and no bag operated quickly and effectively. It was only the extremely covered heads, the ones that they coated ridiculously heavy. They were not a real life example of automotive spray booth heads. Especially since the heads are examined by inspectors every year. If a head is located where paint can get on it, it should be protected better. The head with paint on it already should be replaced as the code calls for. To cover every single head is the where the danger comes in. Modifying an engineered head with a makeshift cover isn't a safe response.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
“Sprinklers protecting spray coating areas shall be protected against overspray residue. Sprinklers subject to overspray accumulation shall be protected using plastic bags having a maximum thickness of 0.003 inches (0.076 mm) or shall be protected with small paper bags. Coverings shall be replaced when deposits or residue accumulate.”

This is funny too. They actually try to sound like they tested other thicknesses of cellophane by stating that the required thickness should be 0.003 inches, but then never give a measurement for the paper. And then to top it all any thickness of paper turns out to be the worst response.

Testing has shown that lightweight cellophane or paper bags will not adversely affect the operation of the sprinkler. Sprinklers protected by the lightweight cellophane or paper bags may require more frequent inspection than the annual inspection outlined in 5.2.1.1.2 to prevent excessive buildup on the bags. Depending on the use of the spray coating area, the inspection and subsequent replacement of the bags may need to be done daily. In prior editions, NFPA 25 allowed the use of a plastic bag, but this was changed due to concerns about the potential for a plastic bag to shrink prior to sprinkler activation and disrupt the discharge pattern.”

This 'testing'. This is what Im looking for. Does anyone know where they did it and where the documentation can be found?

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
The nfpa 33 takes a lot into consideration. It requires cleaning and maintenance, it requires training. It requires protection. This is the only item that for some reason gets this unprofessional treatment.

If the facility trains the employees to not put the heads where they can get paint, and trains them not to spray the paint on the heads. Then trains them to clean the particles of overspray from the accumulated areas near the filters. Then if a head gets paint accidently during maintenance or refurbishing the booth, it gets replaced. Why then would they say the head can be covered to react in a slower response? They require you to protect the area against fire with a wet deluge system, and require that it respond quickly. But then include some foolhardy rube goldberg device. Its like they didnt realy give it much thought.

RE: Covering paint spray booth sprinkler heads, tested?

If you do not want the heads covered do not cover them

As you state Not required


There are numerous types of spray operations and how it is done. Yes possibly covering the sprinklers is not always required.




Do not cover the sprinklers if you do not want to.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
But some Fire Marshals are misinterpreting the code. They think its required.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
So I need to give them proof of tests.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
I just joined the NFPA and placed the question to them to get their official response. Even though the code is written in english, our fire marshal is using a different meaning for the word 'or'. He is substituting the word and.

RE: Covering paint spray booth sprinkler heads, tested?

I kind of read NFPA 13 as "SHALL" be protected

RE: Covering paint spray booth sprinkler heads, tested?

Tom

I would advise the following as someone who worked on the insurance side as a loss prevention representative for 36 years.

Get your insurance carrier (not your insurance agent) to sign off on your plan IN WRITING, if your insurance carrier changes, get them to sign off too. Why because they MAY use the NFPA requirement to not pay a claim for property damage, liability, etc. Be prepared to defend yourself to your management when a claim occurs and they are not reimbursed and or OSHA issues a violation to your company and the negative press should you have a fire. Make sure management has your back, believe me I have been down this road before from the insurance side.

Good luck.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
cdafd, what do you mean? Shall means 'must'. Thats not in question. The ambiguity comes in what is the protection? I can have some person stand in front of the head and block the spray, thats protecting it. I can keep anyone from spraying paint on it, thats protecting it. I can install pop ups that are out of the line of spray and thats a form of protection. Placing them in a good location is the best form of protection because you actually still get the protection of the water spray in a suitable amount of time. Or a survivable amount of time. We agree to protect them, and we agree to replace them if we ever put paint on them. We just dont agree we have to cover them.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
LCREP , I appreciate the advice. And that's what we are in process of doing. I attached a Hanover Insurance write-up, it talks about the poor response time. The thing about Insurance companies not wanting to pay is they would have to explain their reason in court. And the code is very clear if you understand english language words and their meanings. If the code actually said something different it would be a different story.

9.4.7 Sprinklers shall be protected against overspray residue, either by location or covering, so that they will operate quickly in event of fire. 9.4.7.1 Sprinklers shall be permitted to be covered only by cellophane bags having a thickness of 0.08 mm (0.003 in.) or less or by thin paper bags. These coverings shall be replaced frequently so that heavy deposits of residue do not accumulate. 9.4.7.2 Sprinklers that have been painted or coated by overspray or residues shall be replaced with new sprinklers.

The code uses the word 'or'. 'Or' means either . Or also means 'in preference of'. So in sentences the word you put before 'or', is preferential, then the next word after 'or' is the second preferred. These people that write these codes are very smart people. They have a commanding grasp of the english language and choose these words carefully. My problem is for some reason I have a Fire Marshal that is substituting words. He says they meant to say and. He says they should be protected both ways.

Then he says the meaning of 'shall be permitted' is 'must be'. he has even gone as far as to say he actually talked to the committee members that wrote nfpa33 2016 and that 'she' concurs with him.






RE: Covering paint spray booth sprinkler heads, tested?

Read NFPA 13 2016 edition

6.2.6.4.1

No OR in that section

Keep fighting if you want

It has been industry practice for years.

Good luck

RE: Covering paint spray booth sprinkler heads, tested?

Tom:
Again, what is your agenda? Are you a worker in these areas that is looking to have the protection changed because you do not feel safe? Are you an engineer in the design of these systems? Are you the owner of this facility?

The standard of practice has been the paper bags or cellophane, and that is indicated in NFPA 13 - The standard for the installation of fire sprinkler systems.

I think you will be hard pressed to find an engineer or contractor that will back moving the sprinklers so you are protecting them from overspray in that manner. Also, do you have enough spacing left to move them? Sprinklers have a given area of protection and max spacing for spray booths (just like any other occupancy has a given criteria).

I have not heard of an epidemic of people being injured in spray booth fires because of the bags in place.

This seems to be a very strong passion of yours. You may want to consider funding full scale fire tests to provide data to back up your requested changes to the standards. If you can provide evidence from full scale fire testing that there is a significant danger with the bag method of protection, then you could get the standards changed. Remember though, these standards are generalized to apply to all spray booth conditions. You may have a unique situation where other protection methods are viable. If you are a fire protection engineer, maybe you could provide the client with a full performance based design for the area.

Best of luck in your endeavors.

Travis Mack
MFP Design, LLC
www.mfpdesign.com
"Follow" us at https://www.facebook.com/pages/MFP-Design-LLC/9221...

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
TravisMack, I am the owner and a worker at our facility. I am the one to teach the other workers about the equipment also. So in the past I have shown the employees how effective sprinklers are and also told them not to get any paint on them. If you show someone a video of a sprinkler head popping at 40 seconds and putting out a fire in close to a minute. And then show them what a 2 minute fire looks like or god forbid a 3 or 4 minute fire, then they understand that the code is correct in saying they want the head to respond in the quickest time possible. They wont ever get paint on those heads. A fire with a 40 second response is survivable, a two minute is not. This is why they have these devices in the first place. Its not just to protect equipment, its first and foremost to protect me. We are looking for these tests that they keep refering to. If they are referring to the swedish tests and there really has never been any US tests then the code has no right risking peoples lives like this. In the seventies we would just coat the heads with wax and any dust or particulate would hose right off. These are paint booths that are cleaned after every car. The superior finished product depends on a clean booth. We clean the booth from top to bottom. The heads are on the ceiling, no paint ever gets near these heads. These covers are not tested nor approved by any testing company. Its a jerryrigged unneeded device, for a non-existent problem. It must be some old carry over from when paints stayed wet longer and were shot at much higher pressures.

Look at the swedish tests, they were very comprehensive. I attached them.

RE: Covering paint spray booth sprinkler heads, tested?

The other problem is how Fire reacts and how fire sprinklers activate.

The demos are not real life and every fire is not the same

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
The one constant that the swedes proved was that insulating the head with a bag, and trapping air in the bag , caused the head to heat up slower causing it to respond slower. This happpened every time. The code should just call for replacement of heads if paint gets on them and leave it at that.

There will be differences between the demos and real life also, because the fan will be on feeding the fire with fresh air. It will grow faster and the head will respond faster if its uncovered.

RE: Covering paint spray booth sprinkler heads, tested?

Tom:

I think everyone on here is going to say keep the bag protection as that is in the standards. The standards are what we have to live by every day. If we deviate from the standard and , God forbid, there is loss of life and property, then we are fully liable. You appear to have your mind made up on how you want to handle this. You can do whatever you want in your own facility. That is, until you get caught. Then you will have to deal with government entities that have the power to deny your occupancy permit.

So, in your case, I would recommend hiring and FPE to do a performanced based design to determine if you can get what you want. Otherwise, you may have to abide by the decision of the local official. You may find that the cost of all of this is prohibitive, though.

Again, best of luck to you.

Travis Mack
MFP Design, LLC
www.mfpdesign.com
"Follow" us at https://www.facebook.com/pages/MFP-Design-LLC/9221...

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
Someone from the NFPA just agreed with me that its either and not mandatory. Ill let you know if I get more results. Common sense would tell you that an uncovered head is preferable especially since they were designed that way. I told the inspectors that and they seem to be terrified to make a judgement call.

RE: Covering paint spray booth sprinkler heads, tested?

They made the same call I would make

Bag it.

RE: Covering paint spray booth sprinkler heads, tested?

Damn Tom,

I am impressed. Thanks for your knowledge and passion.

I feel compelled to say the "test-data" you are searching for is empirical real life data. Yes, blanketing a sprinkler WILL delay it. Painting it will prevent it from opening. Big difference. If you fully involve a car, the little baggy will no longer exist.

I encourage you to think of how many booths are in operation. You will know far better than any of us. Out of the numerous ones I have done, You are an absolute anomaly. The standards are there to recommend the minimum for all of them.

I have also inspected them. Care to guess what was on EVERY sprinkler when I arrived? You got it, paint.

I was called in to takeover an inspection of an assisted living facility. I had written like 84 painted sprinklers. I noticed the little UL tags throughout the facility. The sprinklers were not old enough for testing. I asked the maintenance guy why they were tested. He indicated that a unit had a fire a couple months before and a lady had died. The sprinkler did not operate. To hell with the money. I wonder if the guy that had been doing the inspections all the years previous had any change in his sleeping patterns....

R/
Matt

RE: Covering paint spray booth sprinkler heads, tested?

Tom,

You have a very unique problem with sprinklers with no paint overspray, in the 1000's of booths I have inspected using paint I can not recall one booth that did not have a painted sprinklers. It is great you called NFPA the only problem is if you call back and talk to another person you will get a different answer. NFPA will provide a written response but that usually takes weeks to get. The Hanover Insurance document you included is similar to what we had. The purpose was to explain the need to cover the sprinkler when we encounter the problem. I would have then with me and handed them out when I knew they would have a paint booth, because like I said the ones I encounter had paint on them.

Let us know how this all ends.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
Sounds like a money maker for the towns, just fine the slobs.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
There are 45000 paint booths with someone in it spraying all day. Thats a lot of people going without decent protection. Not even the same protection as any office worker. Anyone else is protected better.

RE: Covering paint spray booth sprinkler heads, tested?

Tom:
Did you read the posts on 5/26/27 above yours. LCREP has inspected THOUSANDS and 99.999% had sprinklers with paint on them. The standards are written so as to be applied across a broad range of projects. As stated, you have a very unique situation. It is not going to be covered by any standard. If this is so important to you, then you as the owner, can hire a fire protection engineer. Pay them to do a performance based design of your unique facility. Then, provide the data to the AHJ so you can be granted the ability to do as the FPE you hired has determined is appropriate in your unique situation.

I'm really not trying to be argumentative. I just wonder why you haven't gone down the route of a performance based design, as the recognized standard methods do not meet with your approval.

I wish you the best of luck in having your FPE get you the results you want.

Travis Mack
MFP Design, LLC
www.mfpdesign.com
"Follow" us at https://www.facebook.com/pages/MFP-Design-LLC/9221...

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
the code already says you are to replace the heads if you get paint on them. Putting a cover the slow down the response is not a good remedy. Someones grandpa came up with the best solution years ago, replace the heads.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
Im perfectly happy with a 40 second to 60 second response, like the 155 degree heads will give me if they are left unadulterated. Im going to film the response so you guys can see. The cellophane melts and wraps the head with a thick plastic shrinkwrap. Ill do it with 4 digital thermometers and timer.

This video shows a fire in a small room like a paint booth with no sprinkler head responding, and its flashed over in 2 minutes. So to me that demonstrates how my booth will react, if the heads are covered. Then they show a single head responding and its all over in 45 seconds. https://www.youtube.com/watch?v=VEXav_iBEZ8&t=...

There is no need really to do a performance based design because Im happy with my old design. The code is written in english so its easy to decipher. 9.4.7 Sprinklers shall be protected against overspray residue, either by location or covering, so that they will operate quickly in event of fire. Normally if you are writing a sentence and you put a word before the word 'or' it means 'in preference of'. So location is best choice, followed by covering as least desired. I got a reply from the NFPA on this and they said they didnt intend to put location as a preference, they say there is no preference between the two. So hence 'either' is allowed, and either does not mean 'and'.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
The nfpa33 2016 also calls training 'required' and to be documented. So bodyshops are to train their people about static electricity, how the sprinkler works, cleaning the booth, removing the dry overspray, etc. So if 1000's of shops are letting paint get on their heads, then they also arent training. So more violations to be fined. They should just fine the issue. There isnt another profession thats allowed to spray flammables like this, and for the code to interject with an untested device it doesnt seem possible. Why say cellophane? or thin paper? Why measure the cellophane but not the paper. Everything else about the booth and sprinkler system is very technical and has been engineered and tested. Just this rube goldberg device is like that.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
The inspections that are done yearly are to note if a head has paint on it. So someone knows its there. The fire dept then demands they be replaced. And should now just fine them so they can pay for the follow up inspections.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
My fire inspector said he has not seen paint on the bags of other shops. So they dont need the bags either.

I think it needs to be addressed because an uncovered head will save someone's life, and the covered/bagged head will delay it long enough to kill someone.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
The wording of 'location or covering' was added in the 2007 edition. Prior to that they just said 'protect'. My argument back then was that we are the protectors, we as the workers do the protecting. We dont need no stinking baggies.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
I did a test this morning, the uncovered head popped at 155 before the tightly covered cellophane head hit 83 degrees f. The cellophane did not distort or shrink or melt at all at 155. the uncovered head was not loaded with water either, which would keep it even cooler.

RE: Covering paint spray booth sprinkler heads, tested?

You seem very passionate about this topic.

Have you considered using this abundance of energy to have the adopted codes and standards changed based on what you do in your paint booth? None of us here can really help you change the building code.

I can visualize you taking this crusade on the road and educating people from coast to coast with what most of us spend minutes deciding.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
I was in a fire once. Burnt my right side and all my skin fell off my arm and hand. Laquer thinnner fume caught by static. I stumbled outside and it was raining. I remember thinking how nice it was that is was raining right then. It cooled the skin and while the adrenaline was pumping it was enough to soothe it. I've had nightmares about burning and not getting any water.
Now we keep our humidity at 35 percent so we don't get static.
It's all healed and you can only tell in bright light. We won't be bagging our heads.
Like Ive said Ive know about the bags since 1993. I cant believe they are still even considered. A thin wrap of toilet paper might be a good covering.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
I think when im done the code will only allow some other type of cover, probably a pop up mechanical device triggered by smoke or heat.

RE: Covering paint spray booth sprinkler heads, tested?

Tom, what you write here is well respected but it seems to me that you are too focused on your specific booths. Working daily for years on spray booths and turn key installations of large automotive paint shops for practically any automotive manufacturer, I have never experienced sprinkler heads inside booths not getting loaded with paint. Of course it would be great to be able to install the heads in such way that remain clean but to me it is simply impossible. We have run numerous simulations of air dynamics simulating air patterns in production conditions in our booths and scrubber sections and, depending of course of type of system, we always try to install the heads in places where the air flow is not fully developed or running slower. Nevertheless, our experience shows that the heads are getting paint regardless. In the booth and blowing air from above, you might have pendent sprinklers fairly clean but what about the scrubber? What about the exhaust ducts where space is tight and velocities are higher? The heads are always getting loaded.

Moreover, it looks to me in these tests they didn|t use the right type of bags. In the conclusions I read that "...the covers did not burn off during the test, despite the fact that they were located relatively close to the flames". It looks to me like the bags selected were not the appropriate type or they didn't considered other types of bags although NFPA 33 & the NFPA handbook are cited in the report. In addition, the plastic bags used in the test which resulted in 2 to 5 times increase of activation time, were plastic bags made of polyethylene and not cellophane as NFPA 13 & 33 state. Cellophane is not polyethylene and it does not shrinkwrap on the head which can potentially affect response time. Cellophane tends to burn at lower temperatures than the activation of head and therefore does not affect response time, at least to a negligent level.

RE: Covering paint spray booth sprinkler heads, tested?

UFT

You bring up a good point regarding the air plenum and heads being painted. It does not take much for a filter not fitting properly or not installed in a small area for the paint to be on the sprinkler behind the filter and at the top of the duct. Dry filters were the worst for painted sprinklers. I would always ask, what do the sprinklers look like you can not see, after a blank stare they would say what sprinkler? After explaining the requirements for sprinklers behind the filter and at the top of the ductwork they would have that no one ever asked me that question moment.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
I agree to bag the plenum and duct heads because they are in the line of spray. Its the main heads over the cars that the human would be near that I think should be kept clear of any cover. I bag the duct heads and change those bags, but they never get wet spray on them. Its just fine duct particulate. The code calls for trying to place the heads out of the path of spray, If the heads near the car that are overhead are getting paint on them then someone is not 'protecting them' then they should be bagged. Ny point is 'all heads' do not require to be bagged. I tested the correct thickness of cellophane and it shrinkwraps. It starts to shrink at 155, when the head is supposed to blow. So the cellophane blocks the water. A shroud would work better, like strands of cellophane hanging down. It would allow the heat to blow the head and the strands would blow right out of the way and not restrict the water. I attached a picture of what cellophane looks like at 155f.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
If the fire is in the plenum then its out of control already.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
I still have not seen any proof of any real tests on the cellophane or thin bags. Wax is the answer, it melts at 140 and would fall out of the way taking any paint with it, then the heads would not get restricted by paint or bag. A good smear of a wax from a toilet bowl ring on each side of the head and paint wouldnt stick to it. It would wash off.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
cellophane of the described thickness in the code melts at 350 degrees. Well before that it shrinks and wraps the head. Its a bad idea, no one tested that.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
And a paper bag that someone would use is like a lunch bag. It keeps the head cool for 5 minutes. The paper just cooks and the air inside doesn't change much. Very good insulator. In 5 minutes the entire booth is consumed with fire. I'll bet booth fires are always devastating because of the bagging.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
Of the tests I did with bags being placed looser than the picture shows, there was a longer delay, the inside cellophane bag temp was at 86 f when the outside was at 160.

RE: Covering paint spray booth sprinkler heads, tested?

Tom,

All sprinklers have a thermal lag, so we do not expect the head to go off exactly at the temp noted on the sprinkler. In fact unless the sprinkler is rated as a quick response the lag can be a few seconds to over a minute depending on how hot the fire is and the proximity of the sprinkler to the fire. The sprinklers installed in a paint booth are not by code required to be quick response. The sprinklers in the both are met as property protection not life safety.

I was an instructor at a fire training center and set off 1000's of fires to demonstrate how sprinklers operated. We used a 3 sq. Ft pan filled with 1 gallon of alcohol about 2-3' below the sprinkler. Sometimes the sprinkler would go off in 30 seconds sometimes 1 minute, we actually had fires where the alcohol burned and never set off the sprinkler. We had temperature probes at the ceiling and typically had ceiling temperatures over 200f for a head rated at 155-165f, all heads were standard response. The only time the sprinkler would activate within a few seconds were when we used ESFR heads or residential sprinklers.

My point being a lot of variables in testing with many different outcomes so what you experienced may be different just by changing a few variables.

RE: Covering paint spray booth sprinkler heads, tested?

Tom, I am reading your findingsw ith great interest. One thing I would like to comment though is whether the tests are conducted similar to a real case fire scenario meaning letting the bag and head heating up from some distance below, let's say 4 to 5 m, gradually instead of bringing a heat source some few cm away from the head. It would be nice, anyway, to document your results in a document, in a similar way just like the Swedish report.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
Im building a container to hold the heads and actually have them loaded with water. Then I plan on having 2 thermometers inside the bags and two outside and filming the entire tests. We plan on burning paper and automotive paint with cardboard and place the fire at car height and have the heads at 8 feet or so, whatever the standard automotive booth is. Ill probably do ten tests of each variation. Ten with no bags, ten with paper bags, and ten with cellophane bags. They will be slow start and gradual building fires, and no flash explosions. If a car was masked off and had paint sprayed on it and then ignited it would be a very hot fire quickly. So we may try a small building fire and then hit it with 500 degree hot air quickly.

Right now we just use heat and no flame and the swedish tests are accurate with what we are finding.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
Doesnt alcohol burn at a low temp too? Cardboard gives off some intense quick heat.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
LCREP you say 'The sprinklers in the booth are met as property protection, not life safety.', but the code still demands 'quick response as possible'. And we aren't interested in working spraying flammables without life safety devices like quick operating sprinklers. That's kind of crazy. Thats the kind of thinking that started the bag covering. Who cares what happens to the painter, just make sure later the building gets saved.

RE: Covering paint spray booth sprinkler heads, tested?

Tom,

You may want to take a look at FM Global Property Loss Prevention Data Sheets 7-27 SPRAY APPLICATION OF IGNITABLE AND COMBUSTIBLE MATERIALS it covers this topic in 31 pages of detail. The FM Data Sheets are free at http://www.fmglobal.com. Factory Mutual is a global property insurance carrier that has an extensive testing and research division. They are leaders in the fire protection field. Many of the NFPA codes are based on the FM test facility as well as UL. FM has been around for well over 100 years.

RE: Covering paint spray booth sprinkler heads, tested?

I think this is the longest thread I have seen here

RE: Covering paint spray booth sprinkler heads, tested?

To keep it going

Look at Fire history in booths for a year and why

You might find fires are very low and happen because the booth is not maintained or some one is doing something they are not suppose to be doing.




There are other items normally required in booths to eliminate ignition factors, make sure they are in place and a fire should not happen.

RE: Covering paint spray booth sprinkler heads, tested?

I concur with what cadfd wrote. Most fire incidents I have experienced, happened during maintenance/cleaning or something was malfunctioning. Sometimes, simple as that, something is slipped under the nose. A forgotten interlock to shut down the pain mix pumps never responded and the fire in the booth could not be controlled due to the continuation of paint supply. Happened fairly recently. Depending on system we deliver, we install additional measures just for the maintenance phase when the normal systems are down during shut down.

A note for quick response sprinklers, it is not always about life safety when it comes to quick response sprinklers. We install this kind of sprinklers due to lack of separation in combustible filter units where fire can spread very fast outside the scrubber. Also, downward air currents through heads starving for heat to rise upwards is a greater concern for standard response sprinklers.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
Im sure there's very little added risk to the building if they have 2 of the 6 unbagged.

RE: Covering paint spray booth sprinkler heads, tested?

You can change to a dry chemical system and get rid of fire sprinklers.

Every booth I have seen with a dry chem system has paint build up on the walls, floor and duct work. And the fusible links have a build-up of paint. We change the links at each service. We also make sure the nozzle covers are in place, on the nozzles. Depending on the installation of the piping, we may blow air through the piping to blow the nozzle cover off the nozzles.

RE: Covering paint spray booth sprinkler heads, tested?

(OP)
These spray booths you guys see paint on heads, are they for cars?

RE: Covering paint spray booth sprinkler heads, tested?

Tom,

Yes we did, most times the covered heads were the least of my problems. I would see things that have a much greater loss potential such as the following:

Control valve to the sprinklers in the booth turned off.
Ventilation system not being used when paining
Open containers of flammable liquid
Lack of bonding and grounding wires when transferring liquids
Non rated electric in the booth or where flammable liquids are being dispensed, if I had $1 for every radio I saw and box fan......
Poor housekeeping
Painting outside of the booth
No sprinklers or any protection in the booth

So yes not everyone is as cautious as you and your operation. You would be amazed at what your competitors are NOT doing.

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