Permatex Ultra Copper
Safety Information

What's This All About?
We have to ask this question every time we publish one of these pages about a gasket material for use on ceramic charcoal cookers. Why? Because every time someone posts to a forum that they are using something other than what the cooker's manufacturer sells, some folks raise questions about the safety of using said materal. Posters on ceramic charcoal cooker bulletin boards have posted that they were told, either by Rutland or by the manufacturer of their cooker, that the Rutland gasket is not safe for use around food. At various times, posters have indicated that Cotronics has said not to use their product, and then said it was alright to user their product. As result, there have been numerous arguments, sometimes heated, on these bulletin boards about the safety of using various non-original gasket materials on ceramic charcoal cookers. We will do our best to provide you with the information we have been able to accumulate on the subject so you can make an informed decision as to whether or not you wish to use this product on your ceramic charcoal cooker.

It should be also noted that there are two primary uses for this product (Permatex Ultra Copper High Temp RTV Silicone) on ceramic charcoal cookers. One is as an adhesive for installing Rutland and Cotronics gaskets on cookers. The other use is to actually form the gasket itself from this material. The safety discussion for this product centered around the Material Safety Data Sheet (MSDS) statement that under certain conditions, formaldahyde could be formed and released.

What would any document about health and safety be without a disclaimer? Well, here's ours. We don't claim to know if it is safe for you to use Permatex Ultra Copper Hight Temp RTV Silicone on your ceramic cooker. Any opinions stated here are just that, opinions. It is up to you to evaluate the information presented here and make your own decision as to whether or not you wish to use this product on your cooker.

Permatex Technical Data Sheet
The Technical Data Sheet contains very little regarding the safety of this product. There is a single item stating that the material is non-flammable and non-toxic. So, let's look at the Material Safety Data Sheet.

Permatex Material Safety Data Sheet (MSDS)
In the Hazards Identification section, we find:

"Butanone oxime produced during curing is toxic and irritates eyes, nose and throat. Overexposure to the silane may cause coma and respiratory failure."
Then, in the Special Precautions section we find:
"When heated to temperatures above 300 degrees F. in the presence of air, this product can form formaldehyde vapors. Formaldehyde is a potential cancer hazard and a known skin and respiratory sensitizer. Safe handling conditions may be maintained by keeping vapor concentrations below the OSHA permissible limit for formaldehyde."
The first warning doesn't seem to be of any concern since it the butanone oxime is only produced during curing. If one applies this gasket material to the cooker and allows it to cure outdoors, there should be no significant exposure to this chemical.

As we said, most of the discussion centered around the second statement regarding the formation of formaldahyde. Here are what we consider to be the salient points about this issue:

You should carefully read all of the information available before drawing your own conclusion about the safety of using this material on your ceramic charcoal cooker. This is what we conclude:

The carcinogenic risks are associated with inhaling formaldehyde, so we think one could avoid any risk associated with the possibility of it being formed in this application by not inhaling the air exiting their cooker.

Also, the risk is associated with long-term exposure, which of course won't happen in this application. The EPA estimates of the increased risk of cancer from inhaling formaldehyde involve a person breathing air containing a small amount of formaldehyde continuously over their entire lifetime. We don't see an occasional whiff of some air exiting your cooker that may or may not contain significant amounts of formaldehyde vapor a risk to be concerned with.

So personally, we don't think there is a problem using this gasket material. We would use it based on what we know. Everyone has to decide for themselves if they wish to drive a car, drink water from a bottle containing BPA, etc. Read the available information and make an informed decision.

Permatex Ultra Copper High Temp RTV Silicone technical data sheet
Permatex Ultra Copper High Temp RTV Silicone MSDS

BASF Product Safety Summary for Ultraform® Polyozymethylene (Contains information about formaldahyde)
United States EPA Hazard Summary for Formaldahyde       Home       Search Our Site       Email The Whiz       Listen To Whizcast       Whizlog       Buy Whiz Gear       Privacy Policy       Kamado Grille
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