Answer / veerabharathi m

zone is the hazardous area

loop is the connection of the intrument from field to whatever system it is connected

loop may be a close loop or open loop

loop means that teh full circuit from sensing element to control valve through dcs, this loop

instruments is located n particular zone, zone is classified harmful things which mix with air and other chemical o2, n2, h2, etc

Answer / kin

i am asking about fire alarm system.

Answer / dsa

Zones are based on hazardous area classifications, zones r catergorized based on explosive gases which could be present in the area. 
Loop are basically open or closed. Basically in instrumentation a loop is defined from the starting point which is sensor to the end point I.e system. This irrelevant to whatever system u use. 
If your question isn't answered kindly elaborate or provide more details and not just ask general questions!

Answer / faiyaz

loop is communication between one or more smoke detector in single loop connected more then one smoke detector but zone is address of alarm according to the zone we can find which area is to be fire

Answer / pateljayur

DSA i am not asking about field zone classification i am just asking about fire alarm system for there loop and zone ..

ok ...

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