湿化工熄灭系统的1998Edition标准(英文)(doc 26页)

This edition of NFPA 17A, Standard for Wet Chemical Extinguishing Systems, was prepared by the Technical Committee on Dry and Wet Chemical Extinguishing Systems and acted on by the National Fire Protection Association, Inc., at its Fall Meeting held November 17-19, 1997, in Kansas City, MO. It was issued by the Standards Council on January 16, 1998, with an effective date of February 6, 1998, and supersedes all previous editions.
Changes other than editorial are indicated by a vertical rule in the margin of the pages on which they appear. These lines are included as an aid to the user in identifying changes from the previous edition.
This edition of NFPA 17A was approved as an American National Standard on March 31, 1998.
Origin and Development of NFPA 17A
The Dry Chemical Extinguishing Systems Committee was activated in 1952. On April 6, 1983, the Standards Council received a request to assign the subject of wet chemical extinguishing systems to the appropriate committee. Listed systems had been available for some time. After the Foam Committee declined the request, the Dry Chemical Committee was asked to assume responsibility for the project. In May 1983, the Dry Chemical Extinguishing Systems Committee voted to accept the assignment and requested that the Standards Council expand the Committee Scope to include the new topic. The Committee also requested that the new document be identified as NFPA 17A, Standard for Wet Chemical Extinguishing Systems. A subcommittee met in June 1983 to develop the text. In November 1984, the Council approved a request to change the name of the Committee to the Committee on Dry and Wet Chemical Extinguishing Systems. The 1990 edition was a partial revision of the 1986 edition.
The 1998 edition of this standard has been revised to clarify the requirements for protection of unclosable openings and equipment shutdown.
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