Abstract. Coaches are considered the safest mode of road transport for school trips. In the last decade alone, 1191 children were injured in 371 coach crashes in the UK. Consequently, the UK government enforced strict regulations on coach operators to reduce accidents. During 2016, 137 coach operator licenses have been revoked due to operator non-compliance. To increase safety of children travelling by coaches, we previously proposed a safety transport model for validation of coach operators. In this paper, a mathematical model for calculation of safety scores is presented. Real data from two transport organisations was used to test the model. Results show that, the proposed mathematical model works very well, as illustrated in this paper.