It is a known fact that certain sectors and occupations are more dangerous than others. Protecting workers in hazardous conditions – in what is often known as the “3D”, dirty, difficult and dangerous, jobs – is therefore a primary focus of the ILO as part of the efforts to promote occupational safety and health (OSH) system. Priority is given to workers in the most hazardous sectors and occupations, such as agriculture, construction, mining, or ship-breaking, or where working relationships or conditions create particular risks, such as exposure to hazardous agents, such as chemical substances or radiation, or in the informal economy.

Occupational deaths and injuries and work-related diseases take a particularly heavy toll in developing countries, including Indonesia and Timor-Leste, where large numbers of workers are concentrated in the primary and extractive activities mentioned above. The ILO works with governments, employers' organizations and workers' organizations to strengthen national OSH systems, including labour inspections, occupational injury reporting, training and information, and national OSH campaigns.

In addition, the ILO’s health and safety mandate includes helping workers, employers and governments respond to the challenges created by HIV (the Human Immunodeficiency Virus) and AIDS (the Acquired Immunodeficiency Syndrome, caused by HIV).