ISA 12.10

This standard refers only to combustible mixtures created bydusts — such as agricultural, carbonaceous, plastic, chemical, andmetal dusts. Such materials are classified in NEC ^®Article 500 as Class II, Groups E, F, and G.

This standard classifies a location based on its dust cloudconcentration, its accumulated combustible dust layer thickness,and its dust bulk resistivity; it also contains references to, anddata on, the explosivity of common dusts, as well as references tolaboratory equipment and test procedures for evaluating theexplosivity of dusts.

This standard is intended for use by persons trained in thedesign and installation of instrument systems and by inspectionauthorities in the approval of such installations.

NOTE: This standard is not intended to addresshazards created by the emission of Class I combustible gases fromcombustible dusts, e.g., the emission of methane from freshlycrushed coal.

Purpose

This standard recommends procedures for classifying locationsmade hazardous by the presence of a cloud or blanket of combustibledust. It conforms with the U.S. National Electrical Code^® (NEC ^®)* and the CanadianElectrical Code (CEC), and is intended to expand and clarifyboth.

*National Electrical Codes^®and NEC^® areregistered trademarks of the National Fire Protection Association,Inc., Quincy, Mass.

Edition:

88

Published:

01/01/1988

Number of Pages:

46

File Size:

1 file , 620 KB