Trinity tests a modified four inch ET-Plus, and it fails. The impact angle was between four and five degrees. NCHRP 350 requires testing at 0 and 15 degrees, and expect acceptable performance between those angles. If a critical impact condition is identified during the service life of a product, successful testing in that condition is required. In addition, NCHRP 350 requires testing of hardware in the orientation at which they are installed. Trinity encouraged installation at an offset 3’4″ as late as 2013 despite knowing the results of these tests on offsets of 4′.
Trinity Failed Test of 4″ ET-Plus