Worksafe proposed changes to the Workplace Exposure Standards (WES) of 18 substances and the Biological Exposure Indices (BEI) of 4 substances NZNO welcomes your feedback on proposed changes to the Workplace Exposure Standards (WES) of 18 substances and the Biological Exposure Indices (BEI) of 4 substances. WES and BEI are important tools for monitoring worker’s biological and airborne exposure. WES are values that refer to the airborne concentration of substances. BEI are guidance values for assessing biological monitoring results which measures the concentration of a substance – or its breakdown products - in blood or urine or even exhaled air. The monitoring result is compared to the BEI established for the specific substance. 18 substances of WES: Acetaldehyde Allyl glycidyl ether Aniline and homologues Arsenic Benzene Cadmium and cadmium compounds Chromium compounds Copper Diethyl sulphate 4,6-Dinotro-o-cresol 1,4 Dioxane Formaldehyde Hydroquinone Phenol Synthetic mineral fibres Vanadium Vinyl Acetate Zinc Oxide 4 substances of BEI: Arsenic Benzene Cadmium and cadmium compounds Phenol Please find further consultation information here. Further information on WES, including the meaning of WES-TWA and WES-STEL, and BEI is provided in the Glossary sections of the relevant proposal documents. Please send feedback to PolicyAnalysts@nzno.org.nz by 14 August 2020.