Cotronics Gasket
Safety Information

What's This All About?
That's the question we asked when researching safety information for Rutland gaskets, so we'll ask it again! Many owners of ceramic charcoal cookers have replaced factory gaskets with various replacement gasket materials when the original gaskets fail. However, there have been concerns raised about the safety of using these other gaskets on ceramic charcoal cookers. Where did all the concern come from? 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.

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 a Cotronics gasket product 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 Cotronics gasket material on your cooker.

The Letter From Cotronics
In order to try to better understand what might be the source of some of these claims, and to get an actual statement from the Cotronics Corporation regarding the use of their product on a ceramic charcoal cooker, we contacted Cotronics and asked for a letter stating their position. We informed Cotronics that the letter would be published on our website and we did receive permission to do so. Here's the letter:

So, it seems that Cotronics is saying:

  1. They have sold their products to many Big Green Egg owners.

  2. They are unaware of any problems as a result.

  3. They don't make any statement as to the safety aspects of using this product around food.
What to make of this? It would seem obvious that Cotronics has not done any food safety testing, and they make no statements about food safety. Notice that unlike Rutland, Cotronics does not make the "we do not recommend it since we have no data" statement. Where does this leave us? Since Cotronics's letter didn't contain any information regarding the safety of using their product around food, we can look to some other sources of information. Cotronics has published a Material Safety Data Sheet (MSDS) and an information sheet for their product.

Cotronics Information Sheet
Here are some statements from the Cotronics information sheet on their 395 and 397 ceramic tapes:

"Thermeez Fabrics are high strength, flexible, durable, dimensionally and chemically stable and offers excellent electrical resistance. Thermeez Fabrics are woven from Industrial Grade, Asbestos Free, Ceramic Fibers. Thermeez 395 is usable up to 1100F and Thermeez 397 is usable up to 1500F. Thermeez Products are user friendly and unlike fiberglass, non-irritating to the skin. Non-Toxic, Meets OSHA Requirements and Will Not Burn. They are Resistant to molten metal sparks and splashes, most chemicals and solvents."
No statements here either about safety for using their ceramic tape around food. So, let's look at the Material Safety Data Sheet.

Cotronics Material Safety Data Sheet (MSDS)
In the Health Hazard Data section, we find:

Primary Route of Entry: Inhalation, Ingestion
Effects Of Overexposure: nose and throat Irritation and Skin Irritation. Due to their large Diameter (6-12 microns) these Ceramic Fibers are considered nonrespirable and would be expected to cause only minor nose and throat Irritation If inhaled.
These products contains minor amounts of binders which burn out during first heat up.
Then, in the Special Precautions section we find:
Precautions To Be Taken During First Exposure To Heat:
Trace temporary organic binders will burn off during the first exposure to heat. (500-1000° F) carbon monoxide, carbon dioxide, oxides of nitrogen, reactive hydrocarbons may accompany binder burn-off. Use adequate ventilation or other precautions to eliminate vapors resulting from binder burn-off. Exposure to burn-off fumes may cause respiratory tract irritation.
Again, no food safety information, but also no indications of any hazards other than minor nose and throat irritation from inhaling any fibers, and respiratory irritation if you inhaled any fumes during first exposure to heat. So, nothing really scary here that would indicate that the Cotronics ceramic tape would be hazardous to use on a ceramic cooker.

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:

  1. Cotronics has made no data available as to the safety of using their ceramic tape products around food.
  2. Cotronics also does not say that such use is unsafe. In fact, they know it is being used in such an application and do not make any recommendation against using it.
So, it is our personal opinion that there is no significant level of risk associated with using the Cotronics 395/397 ceramic tape products in a ceramic charcoal cooker. But, as we have stated, you should evaluate the available information and draw your own conclusions.

Cotronics ceramic tape products information sheet
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