Interlocks are required in the International Fuel Gas Code in Section 505.1. That code does not pertain to electric equipment. The purpose of the interlock and gas equipment is to prevent operation without adequate combustion air. Incomplete combustion leads to the silent and odorless killer, carbon monoxide.

The proposed revision involves moving Section 505.1 from the fuel gas code to the IMC or International Mechanical Code. The proposed M60 in order to remain consistent is asking that electric appliances now include safety interlocks. That justification to make gas and electric requirements consistent, simply does not apply.

While the proposal stated that no cost impact would occur, the opposite is true. In fact, all manufacturers would need to modify their equipment at a significant cost impact to industry. When these unneeded sensors fail on an individual item of equipment, cooking lines and hood systems would shut down at any given time of day or night.

Imagine your cooking line shutting down during your busy time and the manager must wait until a service company arrives to identify the offending piece of electric equipment. Then remove it from service before the exhaust system can be restarted.

We suggest accessing the public comment form listed above or for more detailed information, go to Tom Johnson’s website at http://www.jdpinc.com/know.htm and refer to IMC Revision objections. Tom Johnson will be addressing this subject and more at the Multi-unit Architects and Engineers Conference on May 19 in Chicago.