The investigations of the relationship between lubricity, coefficient of friction and properties of film lubricant of diesel fuels with low content of sulphur and fuels with additives were carried out. Lubricity of fuel was determined by the HFFR method. The linear relationship was obtained between lubricity and proportional share of surface covered with a thin layer of film lubricant. The coefficient of external friction also showed linear dependence on lubricity. Every investigated fuel, which was characterized by best lubricity showed low coefficient of friction and a large proportional share of surface covered with a thin layer of lubricant.
Safety hazards connected with technical service of agricultural machines on private farms were analyzed. Basic indices of safety were presented. There were described the technical conditions of applied machinery and workshops, where the machines are maintained and repaired. The significant effect of economical, technical and organizational factors on the safety of technical service presented.