Sanders are routinely used on trains to reduce the impact of slippery rail head conditions by blasting sand between the wheel and the rail. RSSB undertook research to find out how the rail industry can optimise the use of sanders. A three-month programme of full scale testing at the Rail Innovation and Development Centre at Melton Mowbray, using two new Class 387 trains loaned by Great Western Railway, generated a robust dataset from over 220 test runs covering various configurations of sanders, test speed and train formation.