# Commission Delegated Regulation (EU) 2017/79 of 12 September 2016 establishing detailed technical requirements and test procedures for the GB type-approval of motor vehicles with respect to their 112-based eCall in-vehicles systems, of 112-based eCall in-vehicle separate technical units and components and supplementing and amending Regulation (EU) 2015/758 of the European Parliament and of the Council with regard to the exemptions and applicable standards (Text with EEA relevance), Division 2.5.4

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

The deviation between IVS location and true location, dIVS shall be calculated using the following equations:
Δφ = φIVS – φtrue
Δλ = λIVS – λtrue
φm=φIVS+φtrue2
dIVS=R Δφ2+cosφmΔλ2
where:
ΔφDifference in latitude (in radian)
ΔλDifference in longitude (in radian)
φm Mean latitude (in unit suitable for the cosine calculation)
RRadius of the earth (mean) = 6 371 009 metres

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Source: https://www.legislation.gov.uk/eur/2017/79/annex/I/division/2/division/2.5/division/2.5.4 (the official version)
Page: https://openlegislation.uk/eu-regulation-2017-79/annex-I/division-2/division-2.5/division-2.5.4
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.