Mitigating the chemical risk in R&D projects: how to ensure workers safety?

The chemical risk is a combination of hazard and exposure. Once the risk is assessed, either reducing the hazard or the level of exposure should mitigated it. In occupational health and safety, the “STOP principle” is applied. It defines the hierarchy of protective measures and groups them. The abbreviation STOP stands for Substitution, Technical measures, Organizational and Personal protective equipment.

 

Substitution approach

 

Eliminating or reducing risks before they are introduced into the workplace is the most effective way of a mitigation management. Both products and processes could be safe-by design. For example it is possible to replace hazardous substance by less hazardous, to replace powders by pellets or to replace manual by automatic process…

 

Technical (engineering) control

 

Installing technical control will remove the hazard at the source, before the workers are exposed. It is a very reliable way to control exposure as long as they are well-designed, used, and maintained. For example, it is possible to isolate the chemicals with dynamic or static barriers, to handle the chemicals in closed systems, to provide ventilation….

 

Nine ventilation principles have been settled by INRS (Institute National de Recherche et de Sécurité) and should be followed:

 

• “Surround the production zone as much as possible
• Capture emissions as close to the source as possible
• Place the hood so that operators are not between it and the pollution source
• Utilize the pollutants natural movements
• Induce sufficient air speed
• Distribute air speed uniformly within the capture zone
• Compensate air exhaust by equivalent air input
• Avoid drafts and thermal discomfort
• After filtering, exhaust polluted air outdoors, away from fresh air intake areas.”

 

Organizational control

 

The organizational controls aim to reduce accident thanks to optimal work methods and procedures. The following items are examples to be settled:

 

• Information, training and regular refresher courses for both workers and managers.
• Procedures both for work (including transport, waste management, housekeeping and maintenance) and for emergencies (spills, fire …).
• Minimizing the duration of exposure and the number of workers involved.
• Access restriction to the work areas.
• Specific medical surveillance
• Labeling chemicals and equipment

 

Personal protective equipment

 

Wearing Personal Protective Equipment (PPE) can only be considered when all other risk mitigation measures are insufficient or impossible to implement.