Influence of groove count on slip resistance using NTL test feet

In recent years, walkway slip-resistance testing with grooved NTL (Neolite Test Liners) has been the subject of research, as well as used in field investigation practices. Recent research shows that differences between non-grooved and grooved test feet do exist, especially under wet conditions. It is not known how the number of grooves influences the slip resistance. This study investigates the influence of groove count on slip resistance under both wet and dry conditions using the PIAST tribometer. Test feet with 1, 3, 5, 7, 9, 11, 13, and 15 grooves and a non-grooved test foot were used. Polished granite and vinyl composition tile were used as test surfaces. Results for both test surfaces show markedly higher slip resistance for increasing groove counts under wet conditions, while under dry conditions, the results show slight increases in slip resistance. Implications of these results are discussed.