Fires cause more property damage, personal injury, and death than any other threat to physical safety. Fire suppression systems typically work by denying a room one of three requirements for a fire to burn. These are temperature, fuel and oxygen. Fire detection systems also help negate these variables through rapid fire detection. Fire detection systems are divided into two general categories, the first manual and the second automatic. The manual, of course, requires a human response such as calling the fire department and manually activating fire alarms. There are three basic types of fire detection systems. Thermal detection systems contain sophisticated heat sensors that can detect heat at a specific temperature or a rapid increase in heat where both will trigger an alarm. Smoke detection systems are the most common means of detecting a fire. Required in most building codes for residential and commercial buildings, these systems can detect smoke in three ways. Starting from photoelectric sensors, smoke is detected via infrared rays which activate alarms when interrupted. A sensing system called an ionization sensor contains a small amount of radioactive material inside a sensing chamber, which when certain combustion byproducts enter the chamber, changes the level of