1. WATER DETECTION
2. FIRE DETECTION & SUPPRESSION
3. SPRINKLER SYSTEMS
4. SMOKE DETECTORS
5. ACCESS FLOORING
6. SECURITY

There are two types of smoke detectors currently in use: the Photoelectric Detector and the Ionization Detector.

 Photoelectric Detector

The photoelectric detector responds to smoke, which deflects a small light beam inside of the detector and activates the photoelectric cell, setting up an alarm. This type is connected to an electrical outlet, and is subject to power failure if it does not have a battery backup.

  Ionizing Detector

The second type is called an Ionizing Detector, and it usually contains radioactive Americium 241 or Radium 226. These radionuclides continuously ionize the surrounding air within the detector, sending a small current of electricity through it. When a smoke particle impedes that current, the electric circuitry monitor sets off an alarm. This type of detector, which works best in a flaming fire, works on a battery and is subject to battery failure. A yearly vacuuming is often recommended for keeping them in good working condition. Some models require occasional cleaning with alcohol.

Photoelectric Detectors are more sensitive to smoke than are the Ionizing type detectors, and although they were originally slower to detect a flaming fire then were the ionizing type, they are now considered to be superior in both types of situation. According to tests performed by the US National Bureau of Standards, the improved photo-electric detectors provide 2 to 3 times more chance of escape than the ionizing type of detector containing Americium. According to an article by G. Blair, in the Journal: Politics and Other Human Interests, 31 January 1978, smouldering fires account for about 75% of all home fires. The photoelectric type detector is currently more expensive than the ionizing type, but affords broader and more realistic protection for common types of fires.