ISA 60079-29-1

W/D S/S BY UL 60079-29-1

This part of ANSI/ISA-60079-29 specifies general requirementsfor construction, testing and performance, and describes the testmethods that apply to portable, transportable and fixed apparatusfor the detection and measurement of flammable gas or vapourconcentrations with air. The apparatus, or parts thereof, areintended for use in potentially explosive gas atmospheres(see 3.1.3) and in mines susceptible to firedamp.

This standard is applicable to flammable gas detection apparatusintended to provide an indication, alarm or other output function;the purpose of which is to give a warning of a potential explosionhazard and in some cases, to initiate automatic or manualprotective action(s).

This standard is applicable to apparatus, including the integralsampling systems of aspirated apparatus, intended to be used forcommercial, industrial and non-residential safety applications.

This standard does not apply to external sampling systems, or toapparatus of laboratory or scientific type, or to apparatus usedonly for process control purposes. It also does not apply to openpath (line of sight) area monitors. For apparatus used for sensingthe presence of multiple gases, this standard applies only to thedetection of flammable gas or vapour.

This standard supplements and modifies the general requirementsfor the type of protection covered in appropriate ANSI standardsof IEC 60079-0. Where a requirement of this standard conflictswith a requirement of the type of protection covered inappropriate ANSI standards , the requirementof ANSI/ISA-60079-29-1 will take precedence.

NOTE 1 ANSI/ISA-60079-29-1 is intended to provide for the supplyof apparatus giving a level of safety and performance suitable forgeneral purpose applications. However, for specific applications, aprospective purchaser (or an appropriate authority) mayadditionally require the apparatus to be submitted to particulartests or approval. For example, Group I apparatus (i.e. apparatusto be used in mines susceptible to firedamp) may not be permittedto be used without the additional, prior approval of the relevantauthority in mines under its jurisdiction. Such particulartests/approval are to be regarded as additional to and separatefrom the provisions of the standards referred to above and do notpreclude certification to or compliance with these standards.

NOTE 2 All apparatus calibrated on specific gases or vapours cannot be expected to correctly indicate on other gases orvapours.

NOTE 3 For the purposes of this standard, the terms “lowerflammable limit (LFL)” and “lower explosive limit (LEL)” are deemedto be synonymous, and likewise the terms “upper flammable limit(UFL)” and “upper explosive limit (UEL)” are deemed to besynonymous. For ease of reference, the two abbreviations LFL andUFL may be used hereinafter to denote these two sets of terms. Itshould be recognized that particular authorities havingjurisdiction may have overriding requirements that dictate the useof one of these sets of terms and not the other.

NOTE 4 For the purposes of this standard, the term “indicatingup to a volume fraction of X %” includes apparatus with an upperlimit of the measuring range equal to or less than X %.

Edition:

13

Published:

06/26/2013

ANSI:

ANSI Approved

Number of Pages:

56

File Size:

1 file , 760 KB