Under Article 4 of this directive, employers are expected to carry out an assessment of the nature, degree and duration of exposure to agents, processes or working conditions in activities where there is a risk of exposure to them. The European Commission is charged with drawing up guidelines for the assessment in consultation with the member states. Under Article 6, pregnant women and breastfeeding mothers should not be obliged to perform work which risks exposure to agents listed in Annex II, Section A and Annex II, Section B respectively of the Directive. The Directive also calls on member states to ensure that breastfeeding mothers and pregnant women are not forced to perform night work.