Task 1: Hazardous substance risk assessment 1 The occupational hygienist (OH) has made some initial measurements of dust levels and gathered other information relating to exposure of workers to vitamin C powder. All of this information is provided in supporting document 1. (a) Explain what the OH should have considered when planning to measure workers personal dust exposure levels. (15) Note: You should support your answer, where applicable, using relevant information from the scenario and the relevant supporting document.