The AOSH investigates the causes of accidents, mishaps and pollution that are reported on the basis of the Act on Working Environment, Health and Safety in Workplaces.

The purpose of the AOSH's investigation is to help prevent this from happening again at workplaces.

The AOSH mainly investigates serious accidents that are reported to the emergency service 112. The administration assesses in each case individually whether there is a reason to conduct a special field inspection, but such an investigation is not always needed when, for example, the causes of an accident are known.