Substitution is an important component of the Harmonised Mandatory Control Scheme (HMCS), and the UK is obliged to implement a strategy to replace chemicals that have been identified as candidates for substitution, or contain components that have been identified as candidates for substitution
During the risk-assessment process, operators are required to consider the selection of products both in terms of the magnitude of their Risk Quotient (RQ) and the presence of hazardous substances, including candidates for substitution. Operators are required to provide a robust defence for the continued use of products that have a high RQ or contain candidates for submission.
Chemical suppliers must consider the advice they provide to operators that justifies continued use of any product containing candidates for substitution. In addition, suppliers should consider an approach for the replacement of any undesirable components, leading to the reformulation and re-certification of products.
Operators are encouraged to select products without a substitution warning. Therefore, a supplier may wish to seek alternatives at the product-development stage. However, there may be good technical reasons why a particular substance cannot immediately be substituted. The supplier should highlight these to operators so that they can include this information in their justification for continued use of the product.