Quick answer: Cobalt oxide WEL is 0.02 mg/m³ inhalable — a Category 1B carcinogen and one of the most stringent WELs in UK occupational health law. Nickel compounds WEL is 0.1 mg/m³ — a Category 1A carcinogen. Both are present in NMC and NCA lithium-ion battery cathode materials. H-Class extraction (99.995% at 0.3 micron, sealed system, no bypass exhaust) is mandatory for any operation generating cobalt or nickel dust. Standard M-Class extraction is not adequate. EV workshops transitioning from ICE servicing must update their COSHH assessments to include battery chemistry hazards.
Electric vehicle battery manufacturing, pack assembly and EV workshop servicing introduce hazardous dust exposures that most existing COSHH assessments do not cover — because most COSHH assessments were written for ICE workshop environments. As the UK transitions to electric vehicles and battery manufacturing scales up, the gap between the existing COSHH framework and the actual hazards in battery environments is becoming a significant compliance risk.
The hazardous dusts in EV battery environments
Cobalt oxide — WEL 0.02 mg/m³ inhalable. Category 1B carcinogen. NMC cathode material. At 0.02 mg/m³ cobalt dust is not visible to the naked eye. Standard M-Class extraction at 99.9% filtration efficiency is inadequate for cobalt dust at these concentrations. H-Class extraction is mandatory.
Nickel compounds — WEL 0.1 mg/m³ inhalable. Category 1A carcinogen. Present in NMC and NCA cathode materials alongside cobalt. Any operation generating cathode material dust generates both cobalt and nickel dust simultaneously. H-Class extraction is mandatory.
Lithium compounds — present in anode materials and electrolyte systems. Lithium reacts with moisture — extraction systems used for lithium dust must be compatible with lithium reactivity. Standard wet/dry vacuums are not appropriate.
Carbon black and graphite — anode materials. Both electrically conductive. Standard vacuum exhausts that recirculate fine particulate deposit conductive carbon dust on electrical equipment creating short-circuit risk. Sealed H-Class extraction with no bypass exhaust is required.
What this means for EV workshops
A franchised or independent EV workshop carrying out battery pack servicing needs to review its COSHH assessment for battery chemistry hazards. The existing assessment almost certainly covers engine oils, brake dust and general workshop chemicals. It almost certainly does not cover cobalt, nickel and lithium compounds from battery cell dust. The practical triggers for a COSHH assessment update:
- Any work that opens or disturbs battery cell modules
- Any work on battery pack internals after thermal runaway
- Any battery disassembly at end of life
- Handling of battery modules where cell damage has occurred
What COSHH requires
The COSHH hierarchy of control for cobalt and nickel dust in battery environments: substitution where LFP chemistry can replace NMC/NCA; enclosure for the most hazardous cell-level operations; H-Class LEV at source connected directly to the operation; RPE as a supplement to LEV, not a replacement — face-fit tested FFP3 minimum for cobalt dust operations. LEV must be examined and tested at least every 14 months under COSHH Regulation 9.
Gigafactory and battery assembly operations
At gigafactory scale — electrode coating, slitting, cell assembly, formation cycling, module assembly — the dust generation points are numerous and the extraction requirement is significant. Multi-motor H-Class extraction with high airflow and auto-clean filter is the specification for sustained production environments.
Contact the V-TUF technical team to discuss extraction specification for battery manufacturing operations: 01522 787978
Further reading: EV and electric vehicle servicing | Lithium battery manufacturing | H-Class dust extraction | COSHH Regulations 2002 | HSE EH40 | Choose the right machine for the job
