Safe concentration of benzene exposure as reference for determining threshold limited value in enviromental working

Background: The aim was to measure the limits of the safe concentration of benzene in the shoe home industry in Romokalisari Surabaya. Method: The study was pre-experimental study with single group design. Samples taken were 25 workers at shoe home industry in Romokalisari, Surabaya. To determine the safe concentration of benzene for workers obtained data on weight of experimental animal (W animal), body surface of experimental animals (BSA animal), weight of workers (W), height of workers (h), body surface area of workers (BSA), breathing rate of workers (BR), working time (t), concentration benzene, Animal Km, Human Km, NOAEL, and safe human dose (SHD). Results: The average measurement of benzene concentration was 1.98 ppm (6.34 mg/m³), which means it was above the threshold value (TLV) at Indonesia. The safe limit value of benzene concentration of 0.0275 ppm also exceeds the stipulated level of 0.009 ppm daily for acute effects and 0.003 ppm daily for chronic effects. Conclusion: Control efforts are needed so that workers are protected so they are not adversely affected by benzene exposure. The recommendation such as use appropriate personal protective equipment and plant a number of ornamental plants that can absorb and reduce the concentration of benzene.