The development of toxicologists’ needs for reliable and robust Based on EpiSkin2007 as the Draize skin irritation replacement reference test method, we present and discuss here theresults obtained by adapting protocols to the SkinEthicThe main adaptations of the validated reference protocol consists in a modulated exposure time (15, 42or 60 min) followed by a rinsing step and a 42 h post-incubation period before quantitative measurementof cell viability by MTT reduction. The results obtained with a set of 39 test substances allowed to determinea prediction model with a cut-off of 50%. The best reliability was obtained with the proposed ‘‘42bis” (42 min + 42 h) test method. An overall accuracy of 85% was reached when testing the 20 ECVAMselected reference test substances. The performance of this optimized test method was confirmed byits higher robustness compared to other proposed protocols. As such, none of test substances showeda standard deviation above 18%. This optimized skin irritation protocol has thus been established accordingto the ECVAM intra-laboratory minimum performance standards.in vitro protocols able to discriminate skin irritants from non-irritants integrates thein vitro tools for screening test substances.TM test method, validated by ESAC (ECVAM Scientific Advisory Committee) in AprilTM Reconstructed Human Epidermis (RHE) model.