# Commission Regulation (EC) No 692/2008 of 18 July 2008 implementing and amending Regulation (EC) No 715/2007 of the European Parliament and of the Council on type-approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5 and Euro 6) and on access to vehicle repair and maintenance information (Text with EEA relevance), Division 2.3.1.4

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

Bench-ageing time. Bench ageing time shall be calculated using the bench ageing time (BAT) equation as follows:
te for a temperature bin = th e((R/Tr)–(R/Tv))
Total te = Sum of te over all the temperature groups
Bench-Ageing Time = A (Total te)
Where:
A 1,1 This value adjusts the catalyst ageing time to account for deterioration from sources other than thermal ageing of the catalyst.
R Catalyst thermal reactivity = 17 500
th The time (in hours) measured within the prescribed temperature bin of the vehicle's catalyst temperature histogram adjusted to a full useful life basis e.g., if the histogram represented 400 km, and useful life is 160 000 km; all histogram time entries would be multiplied by 400 (160 000/400).
Total te The equivalent time (in hours) to age the catalyst at the temperature of Tr on the catalyst ageing bench using the catalyst ageing cycle to produce the same amount of deterioration experienced by the catalyst due to thermal deactivation over the 160 000 km.
te for a bin The equivalent time (in hours) to age the catalyst at the temperature of Tr on the catalyst ageing bench using the catalyst ageing cycle to produce the same amount of deterioration experienced by the catalyst due to thermal deactivation at the temperature bin of Tv over 160 000 km.
Tr The effective reference temperature (in °K) of the catalyst on the catalyst bench run on the bench ageing cycle. The effective temperature is the constant temperature that would result in the same amount of ageing as the various temperatures experienced during the bench ageing cycle.
Tv The mid-point temperature (in °K) of the temperature bin of the vehicle on-road catalyst temperature histogram.

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Source: https://www.legislation.gov.uk/eur/2008/692/annex/VII/division/2/division/3/division/2.3.1/division/2.3.1.4 (the official version)
Page: https://openlegislation.uk/eu-regulation-2008-692/annex-VII/division-2/division-3/division-2.3.1/division-2.3.1.4
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.