Bruce,
Thanx. I know i need to go through CODES but your explanation is very helpful.
Cheers!!
Amit
Amit:
You must find and study a copy of the international codes to get an "exact" understanding of the classification you stated. However, this is a summary:
Zone 2 implies that under normal operating conditions (and this includes normal maintenance) , an explosive atmosphere will not accumulate in the area. Zone 2 also says that the potential hazard is from a flammble/explosive gas. Groups IIA and IIB are references to auto-ignition temperature ranges; IIA is for the highest of the flammable gases/vapors. Reference standard for Group IIA is propane, and Group IIB is ethylene (most liquid, flammable solvents are also in IIA). FYI, Group IIC is essentially reserved for very low autoignition temperature acetylene and hydrogen. T3 is a temperature class, for Group II materials, with a threshold of 200 degrees Celcius.
Since you do not know this, I assume that you are only responsible to assure that the specifications for all electrical devices meet the requirements of this class, that appropriate consideration is made to control any spark producing activities in the area, or that adequate training and signs are included (or that you are just curious). If you have been assigned ANY other responsibility, you MUST seek expert help recognized by and familiar with your local jurisdiction, or there is risk on your shoulders against which you cannot defend yourself.
... Bruce D. Bullough ...
Lead Process Engineer
Foth Production Systems, LLC
8550 Hudson Boulevard North, Suite 100
Lake Elmo, MN 55042
Direct: +651-288-8598 Fax: +651-288-8551
<a href="http://www.foth.">http://www.foth.</a> com
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[PipingDesign] Hazardous zone
Hi all,
This is Amit working on a project of Lubrication Oil Skid for refinery.
Can any one please tell me how the Hazardous Zones are classified and on
what basis. What is exact meaning of the words in "Zone 2 / Gas Gr.IIA,
IIB / T3"
Thanx
Amit
Pune
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Received on Fri Mar 23 01:40:00 2007
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