Spray-On Fire Proofing in Steel Structures

a client used Carboline Nullifire system on their steel structures (they're in the Oil & Gas industry). you may visit their site (Carboline) for more info and answers to your question.

some surface preparation obviously have to be done on the steel materials, but all that will be performed by Carboline technicians. they don't just sell the coating materials, they install it, too, as a package. so you don't have to worry about improper or incorrect application of the coating.

I would think that it is unnecessary to peel off the coating to accommodate other building structures.

HTH!

The purpose for fireproofing beams is to ensure the strength of the structure long enough for evacuation and fire suppression. If you know which brand & type of fireproofing, contact the manufacturer for guidance. If not, do the adhesion test.

As for replacing fireproofing removed for support of auxiliary equipment, you need to ask yourself if the unprotected area were subjected to extreme heat, would failure of that section reduce the overall integrity of the structure. Include in your determination the secondary loading and shear effects cause by the loss of strength of that piece. Depending on the size of the beam, a 1 ft² area could be large enough to make that beam to sag or lean, causing additional stress on adjoining beams which they may not be able to absorb.

As one of the perpetrators of similar heinous retardent removals I have to chime in on this... I have frequently had to attach temporary hang points for loads in excess of 2tons/point to structural beams, for obvious safety reasons I need to attach to the beam, not the usually flakey fire retardent which wouldn't hold up my pants let alone a chain motor lifting two tons. We have always made the smallest possible removal of material with the understanding that this is part of the fire safety/evacuation system but not everyone doing this kind of work is as aware or considerate as I am...

I can say without hesitation that it is sometimes absolutely imperative to remove a portion of this material to put in equipment like a new chiller or air duct or cable trough or lighting or... so any statements to the contrary need to be re-considered, and then there's the fact that there are people doing work like mine who aren't going to think twice about slicing a chunk out to get a beam clamp in position whether or not it is the 'right' thing to do; so if anyone can provide a good answer to this inquiry I would appreciate it. It might give me the means to pursue a change in practices in my industry which could be creating problems.

HS,

I agree with everything you said. It's not that we can't remove the stuff; we just have to restore the integrity of the protection. Usually this means spraying, squirting or wrapping over the beam clamp or other attachment along with the area of the beam which was uncovered. In terms of fireproofing, the clamp is now part of the protected area. Having spent 20 years as an industrial electrician, I've done my share of scraping the stuff off and replacing it after installing a hanger. It's a little more work & expense, but the first time an investigator says that the flames expanded because the fire wall was compromised by your penetration (even if it would have made no difference), the costs of defending yourself in a lawsuit will pay for more firestop than you could ever use.

This is no different than making a penetration through a fire wall while doing a retrofit. Once the duct/pipe/wire/whatever is installed, it's standard procedure to seal the opening around the new equipment with firestop caulk. I used to keep a small can of the caulk in my tool pouch for quick repairs. For a larger area on a beam, spray coating might be cheaper & quicker to apply.

Thanks for your reply pwr. You've just opened up a can of questions though...

The work I do is usually temporary in nature, with points staying up for as little as a couple minutes. Under these circumstances it is probably not fiscally reasonable to be making these patches all the time, so we come back to the question 'how big a gap makes a difference?'. If we could reasonably remove a 6" section of retardent along the bottom flange of structural beam (well call the flange 1/2" thick by 6" wide just to have an example) then the impact my business is having would be negligible... if however any removal constitutes an effective system failure... well then don't go into any building where my kind have been (you probably can't find such a building outside of residential structures)... I know now you're asking 'Just what exactly is 'your kind''... I have many titles and job descriptions, for our purposes today I'll call myself an 'Entertainment Rigger'... anytime you have been to a corporate meeting or special event where lighting in addition to the normal building lights was used you can safely bet one of us has been there, seen a giant christmas wreath hanging off the corporate building downtown? that was probably us too. We hang trusses off beams (usually with chain motors) then we hang lights, speakers, projectors and all manner of other nonsense off the trusses. For the most part the facilities we frequent have already been 'modified' to accomodate our hanging points (usually by the first guy that hung a point there) however it is not at all unusual for us to have to make alterations in order to perform our tasks, sometimes the alterations are to the building (usually with consent of the owner/manager), sometimes the alterations are to our plans.

If leaving any gap poses a risk then I need to know what sort of fixes are out there...

Does the patch medium need to be matched to the existing material?

Are there inexpensive 'spray-on' products that could be used without special training?

What about some sort of pad that could be clipped, taped, tied or otherwise temporarily attached to cover the gap? I think this might be the best solution from my perspective... assuming such a thing exists...

Believe me, I completely understand the liability issues here... as a rigger my primary function is to protect my employers insurance policy by making certain it is never needed.

Most building beam fireproofing is by a sprayed on coat of vermiculite plaster.

Google will quickly find you makers of premix patching mixes to repair any damaged surfaces.

If you are likely to need to remove fireproofing, no matter how small the area, it would probably be a good idea to get some of this and have it readily available to make good the damage you do.

It is quick to mix and apply, and protects you from the inevitable witch hunt if the building collapses in a fire.

The power generation industry also uses a plaster based on calcium silicate. This is also quick to use, if somewhat messy.

Thank you all for your input on limited exposed areas of structural steel. Does anyone have any insight with regards to potential water damage? If other insulation materials are wetted, then it is my understanding that it no longer holds the same "R-value" and must be replaced. I have not heard of any similar recommendations for spray-on fire proofing. I'll ask the first question again. If it was wet, but is now dry, and appears to be in good shape (i.e. not delaminating), should it be tested for adhesion? Should it be replaced?

ok, now you've phrased your question more clearly.

I was under the impression that the structures were *new*, that's why I pointed you to a possible vendor.

for your situation, determine who was the service provider for the fireproofing, and contact them directly. they can give you the answer in a phone call. up to this time, all the discussions on your question have been indirect and practically off-topic.

Calcium silicate insulation used by power stations is mixed as a paste and applied wet.

When dried out it will retain it's properties.

When wet, it will probably give somewhat reduced R value until dry again, but does not seem unduly affected by wetting and drying.

Contact the manufacturer for more info.