Numerical changes
Some contaminants have lower or higher future values, or a changed combination of TWA, STEL or peak-limit treatment.
WES → WEL 2026 · Factual reference
WES vs WEL in Australia: what changes in 2026?
From 1 December 2026, Australia's Workplace Exposure Standards (WES) are replaced by Workplace Exposure Limits (WEL) for airborne contaminants. The change is more than a new acronym: some listed limits, entry structures and notations also change.
The timing matters
Until the end of 30 November 2026, the current WES list remains the applicable national model reference. From 1 December 2026, the WEL list is intended to take effect following implementation into Commonwealth, state and territory WHS laws. Confirm the position in your jurisdiction before relying on a transition date for workplace decisions.
What is WES?
WES means Workplace Exposure Standards for airborne contaminants. The WES list sets airborne concentration values for listed contaminants and remains the current reference during the transition period.
What is WEL?
WEL means Workplace Exposure Limits for airborne contaminants. Safe Work Australia says the change in terminology is intended to make it clearer that the published values are limits not to be exceeded, and to align Australian terminology more closely with international practice.
Is WEL simply a renamed WES list?
No. Many limits remain unchanged, but the review also produced substantive changes. These include lower or higher numerical values for some contaminants, changes in limit type, new and removed entries, merged or split listings, renamed entries and changes to notation. Thirty-three non-threshold genotoxic carcinogens also move away from numerical exposure-limit treatment.
NTGC treatment
Thirty-three non-threshold genotoxic carcinogens no longer have numerical WELs from the transition date.
Nine limits not changing
A June 2026 ministerial decision means nine proposed numerical changes will not take effect on 1 December 2026.
Have a chemical inventory?
BecSpec's experimental WEL transition screener can compare inventory substance names against the published transition evidence and flag confirmed changes, review cases and unresolved entries. It is a screening aid, not a compliance or exposure assessment.
Official source
Safe Work Australia — Workplace Exposure Limits, airborne contaminants ↗