OECD Room Document - Limitation on technical extension to modified models of protective structure in OECD, Codes for testing of protective structures (Codes 4, 6, 7, 8 and 9)

Since 2007 edition of Codes concerning the tests on protective structure the +/- 7% of the deflection/force reached in the original test (e.g. point 3.9.2.2.2.2 of the Codes 4) has been introduced as limitation for extensions of test results to modified models of the protective structures when validation tests are carried out (e.g. point 3.9.2.2.2 of the Codes 4). The +/- 7% of the deflection/force reached in the original test limit has been introduced into the Codes to reduce the possibility for manufacturer to use the extension procedure as a "shortcut" to have under the same model and OECD approval number protective structures significantly different. The aim of this paper is to share experience with other testing stations and Coordination Centre on problems met in the application of this limit, discuss about its validity, and propose alternative limits to avoid inappropriate use of technical extension procedure