From the USITT Standards Committee:
Fiberglass Fire Safety Curtains
Keep Fire Safety Curtain Safe
USITT Standards Chair
The subject of fire safety curtains has been much discussed recently as a result of the activity by the NFPA and ESTA to write new standards for these devices.
At the Engineering Commission meeting in Toronto a rumor arose that getting a fiberglass fire safety curtain wet or painting it required replacement.
It should be pointed out, obviously, that none of this applies to deluge curtains.
After some research, here are the facts according to the major manufacturers:
During manufacture, a water soluble slurry of Vermiculite is frequently applied to the fabric and the water dried off. When vermiculite dries after the curtain gets wet after manufacture, it can be stiff or boardy. Breaker bars are often used to break down the stiffness and soften the fabric. Additionally, the addition of water can re-dissolve the coating resulting in the possible removal of the vermiculite coating.
If a fire curtain has gotten wet, have it inspected by someone qualified and experienced in evaluating fire safety curtains.
If a fire safety curtain is painted, all of the above comments apply with additional and even more important considerations. The fabric curtain, as constructed by the manufacturer, is a listed product. Listing means that a product has been tested by an organization acceptable to the "Authority Having Jurisdiction" (AHJ), in this case the local fire or building department, and found suitable for the intended use.
Any alteration to the fire curtain will void the listing. Painting the fire curtain would be such an alteration. The listing/labeling agency's position is that the material has to be tested by them to be acceptable under their listing requirements.
There are some additional concerns depending upon the type of paint.
1) Water based paints: By painting with water based paints, portions of the coating may be removed and a poor painting job could result. Also water based paints are normally latex based. Latex paints are usually flammable.
2) Non-water based or solvent paints: Vermiculite coated header wrap, which is used on racing cars, is often painted with a high temperature paint that does not affect the coating. The drawback is that it is solvent based.
In any case, fire safety curtains are not tested (listed) painted and painting, therefore, cancels the listing.
If a curtain has been painted, you should get a qualified expert knowledgeable in fire safety curtains to inspect it and then work with the AHJ to get it accepted if possible. In a worst case scenario, the fabric may need to be replaced.
Please note that many asbestos fire safety curtains were painted to encapsulate the asbestos, so this provision does not directly apply to them. Again, any change to a listed product potentially cancels the listing. However, maybe this is a good time to consider replacing an asbestos curtain. Again I would recommend the curtain be inspected by a qualified person knowledgeable in fire safety curtains.
The new NFPA fire safety curtain requirements (included in the next revision of NFPA80), if adopted as currently drafted, require an annual inspection of the entire system by a qualified, experienced person. More about the specifics of this standard after final adoption will be distributed this summer.
Those who have not already done so are urged to read the article on fire curtains in the current issue of TD&T.
Assisting in the preparation of this article was John Snook of Thermotex.