WorkSafe NZ has published a commentary on the Workplace Exposure Standards and the Biological Exposure Indices to help clarify what they are and when they should be used.

As well as noting that 11 WES values were reduced this year, and 17 BEI were lowered or adopted, the regulator issues a caution about the use of these tools.

"While PCBUs must understand and manage the risks of hazardous or toxic substances at work, we do not recommend untrained people use WES to determine compliance. WES are guidance for qualified occupational health practitioners."