The manufacturer has issued the following safety notice:
InSinkErator UK Issues Safety Notice for corrective action in certain disposers
InSinkErator is undertaking a voluntary corrective action plan that affects some installations of certain models of disposers. InSinkErator has determined that improper installation of the disposer or damage to the air switch can result in a potential fire hazard.
If your disposer is activated with an air switch, your unit may need corrective action . If your disposer is operated by a wall switch, your unit is not part of the corrective action and no work needs to be done.
What to do
Look at your disposer and search for a tube coming from a sinktop switch into the side of the unit. If you cannot find a tube connecting from a sinktop switch to the disposer or if the tube enters the bottom of the unit instead of the side of the unit, your unit is not part of the corrective action and no work needs to be done.
Below is an example of the affected unit with the tube entering the side of the unit.
If your unit is activated by an air switch, has a tube between your sink top switch and the side of the unit and does not have a yellow tag at the end of the cord, your unit is part of the corrective action. If you have an affected unit please follow this link http://www.insinkeratorsafetynotice.com/safety-information for the full safety notice and details on corrective actions.