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ISO 23431:2021

ISO 23431:2021

Measurement of road tunnel air quality

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General Information

Status :

Active

Standard Type : Main

Document No : ISO 23431:2021

Document Year : 2021

Pages : 31

Edition : 1

Section Volume : Ambient atmospheres (ISO/TC 146/SC 3.)

ICS : Ambient atmospheres (13.040.20)Tunnel construction (93.060)

This document describes methods for determining air speed and flow direction, CO, NO and NO₂ concentrations and visibility in road tunnels using direct-reading instruments. This document specifically excludes requirements relating to instrument conformance testing.