4,4’-Methylene bis (2-chloroaniline) is primarily used as a curing agent for polyurethane pre-polymers in the manufacture of castable urethane rubber products. It is a carcinogenic substance that can directly damage the DNA in humans. The aim is to limit occupational exposure to such substances to a concentration that corresponds to 4 extra cancer cases per 100,000. The prohibitive risk level is 4 per 1,000. The Dutch Committee on Occupational Exposure and Safety (DECOS) of the Health Council of the Netherlands has estimated which air concentrations correspond to these risk levels. The Committee derived concentrations of 0.026 milligram (mg)/per kubic metre (m3) and 2.6 mg/m3, respectively. The Committee also recommends to take into account that dermal absorption of 4,4’-methylene bis (2-chloroaniline) can contribute substantially to the risk of cancer.