Regulatory risk assessment approaches for synthetic mineral fibres

- Exposure to synthetic mineral fibres may occur in a number of workplace scenarios.
- To protect worker health, workplace exposure limits have been established.
- For RCF/ASW, worldwide derivation methods and associated OELs differ widely.
- Such discrepancies prevent appropriate risk management of SMF worldwide.
- A harmonised approach to fibre risk assessment and limit-setting is required.

Exposure to synthetic mineral fibres (SMF) may occur in a number of workplace scenarios. To protect worker health, a number of different organisations worldwide have assessed the health risk of these materials and established workplace exposure limits. This paper outlines the basic principles of risk assessment and the scientific methods used to derive valid (justifiable) occupational exposure limits (OELs) and goes on to show how, for SMF, and particularly for refractory ceramic fibre (otherwise known as aluminosilicate wool, RCF/ASW), the methods used and the associated outcomes differ widely. It is argued that the resulting differences in established OELs prevent consistent and appropriate risk management of SMF worldwide, and that development of a transparent and harmonised approach to fibre risk assessment and limit-setting is required.