There was an incident at our workplace which could cause employee exposure. What is the correct procedure in these cases?

The employer must do a risk assessment of the incident, notify all employees of the incident and inform them about potential health risks and precautionary exposure prevention measures. Only employees conducting repair work or other essential tasks are allowed to work in the exposure area for brief periods while wearing appropriate protective clothing. They are also required to wear personal respiratory protection. Working in the exposure area without appropriate protection is strictly prohibited.