Power gating circuitry 244 can be used to selectively couple and de-couple components from a power bus. De-coupling a component from a power bus insures that the component does not incur any quiescent current loss, and therefore can extend battery life beyond that which it would be if the component were not so de-coupled from the power bus. Power gating circuitry 244 can be a switch such as, for example, a MOSFET transistor. Even though a component is de-coupled from a power bus and does not incur any current loss, power gating circuitry 244 itself may consume a finite amount of power. This finite power consumption, however, is less than the quiescent power loss of the component.
It is understood that although hazard detection system 205 is described as having two separate processors, system processor 210 and safety processor 230, which may provide certain advantages as described hereinabove and hereinbelow, including advantages with regard to power consumption as well as with regard to survivability of core safety monitoring and alarming in the event of advanced feature provision issues, it is not outside the scope of the present teachings for one or more of the various embodiments discussed herein to be executed by one processor or by more than two processors.