# Commission Delegated Regulation (EU) 2017/654 of 19 December 2016 supplementing Regulation (EU) 2016/1628 of the European Parliament and of the Council with regard to technical and general requirements relating to emission limits and type-approval for internal combustion engines for non-road mobile machinery, Division 7.3.2.4: Drift verification

Extent: E+W+S+N.I.

After quantifying exhaust gas, drift shall be verified as follows:
(a) For batch and continuous gas analyzers, the mean analyzer value shall be recorded after stabilizing a zero gas to the analyzer. Stabilization may include time to purge the analyzer of any sample gas, plus any additional time to account for analyzer response;
(b) The mean analyzer value shall be recorded after stabilizing the span gas to the analyzer. Stabilization may include time to purge the analyzer of any sample gas, plus any additional time to account for analyzer response;
(c) These data shall be used to validate and correct for drift as described in point 8.2.2.

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Source: https://www.legislation.gov.uk/eur/2017/654/annex/VI/division/7/division/7.3/division/7.3.2/division/7.3.2.4 (the official version)
Page: https://openlegislation.uk/eu-regulation-2017-654/annex-VI/division-7/division-7.3/division-7.3.2/division-7.3.2.4
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.