choosing the right detector

[electahar]

Hi,
I want to know the difference between the detectors listed below and how to choose the right detector for the right application :
- Smoke detector
- Heat detector.
- rate of rise detector.
- flamme detector.
- gases detector (H2, CH4,etc.).
could you give me any information, links or previous topics in the forum.
i'll appreciate it.
thank you.

[WaterbryVTfire]

electahar...
send me a PM with your email. I'll get you info on meters for gas needs.....