A group of 121 maternity staff at Basildon Hospital in Essex have secured a landmark settlement worth £735,000 after being exposed to dangerously high levels of nitrous oxide in their workplace. The settlement, which includes 85 midwives, represents the largest group legal action ever brought by midwives in the United Kingdom, according to the Royal College of Midwives (RCM).
The staff members reported experiencing fatigue, anxiety, headaches and "brain fog" after breathing in the gas, also known as Entonox, which is used to provide temporary pain relief during childbirth. According to an internal hospital report, some staff were exposed to levels up to 30 times higher than the legal workplace exposure limit between 2021 and 2023. More specifically, routine testing in June 2021 recorded one staff exposure of almost 3,000 parts per million, against a workplace limit of 100 parts per million.
A critical failure in the trust's response was the delay in informing staff about the danger. Although the Mid and South Essex NHS Foundation Trust commissioned testing that revealed the breach of safety thresholds, staff members were not told about these results for 16 months. Daniel Poet, from Thompsons Solicitors, who represented the workers, highlighted this delay as unacceptable:
"The trust knew about the dangers in 2021, but staff weren't told until the following year and it took another year for safety measures to be introduced. That delay is unacceptable."
The trust's failures extended beyond communication. The trust attributed staff exposure to poor ventilation and leaking gas lines, indicating systemic infrastructure problems that went unaddressed for months. An independent review deepened concerns about the trust's handling of the situation. A Good Governance Institute review found an "unacceptable delay" in the trust's response and said staff faced "unnecessary risk or potential harm".
What did the RCM say about the settlement?
The Royal College of Midwives described the settlement as a watershed moment for the profession. Gill Walton, the RCM chief executive and general secretary, stated that
"For years, midwives at Basildon were breathing in nitrous oxide at dangerous levels while they cared for women and babies. Even once the problem had been discovered, it was more than a year before staff were told. That is simply not acceptable and no midwife should ever be treated that way."
Walton emphasised the broader significance of the case, saying
"This is a landmark settlement for our members and it should make every NHS employer sit up and take notice. If you don't protect your staff - the RCM will hold you to account."The union has since written to every NHS trust in England to alert them to the risks associated with nitrous oxide use and has worked directly with the Health and Safety Executive (HSE) to update and improve guidance on Entonox.
How did the trust respond to the settlement?
The Mid and South Essex NHS Foundation Trust acknowledged its failures and apologised to the affected staff. Louise Crosby, the chief nursing and quality officer for the trust, said:
"We have acknowledged that we should have acted faster to address the issues and have apologised to staff. Since the incident we have learnt lessons, and as part of this, we have improved our oversight of the monitoring of medical gases across the maternity unit at Basildon Hospital."
The trust has taken remedial action following the exposure incident. It installed scavenger equipment at the maternity unit designed to extract nitrous oxide from the air, and stated that women can have confidence that it is now safe to use Entonox for pain relief during labour.
What regulatory action followed the exposure?
The Health and Safety Executive conducted an investigation into the trust's handling of the incident. The HSE found breaches concerning staff information, instruction and training, and failure to review controls after adverse monitoring results; the trust addressed the breaches and no further action was taken.
The severity of the situation became apparent when the maternity unit took the step of temporarily suspending gas-and-air use in January 2023. This decision came after air-quality testing produced contradictory results, leaving managers uncertain about the reliability of their understanding of conditions in the unit.
How many staff were affected and what compensation did they receive?
The settlement covers 121 staff members, with 85 of them being midwives. NHS Resolution, which manages legal claims and compensation cases on behalf of the NHS in England, confirmed the payouts totalling £735,000. A spokesman stated:
"We can confirm that 121 claims have been settled for a total of £735,000. Some other claims remain outstanding. We are unaware of any larger group of claims brought by midwives."One additional claim has yet to be settled according to the RCM.
Daniel Poet, representing the workers, expressed both satisfaction and concern about the outcome:
"We are proud to have secured compensation for our clients, but they should never have been put at risk in the first place."
Key Facts
- Staff at Basildon Hospital maternity unit were exposed to nitrous oxide levels up to 30 times higher than the legal workplace limit between 2021 and 2023
- The trust delayed informing staff about safety breaches for 16 months after testing revealed the problem
- The settlement of £735,000 for 121 staff represents the largest group legal action ever brought by midwives in the UK
- The trust has since installed scavenger equipment and improved monitoring of medical gases at the maternity unit
- The Health and Safety Executive found breaches in staff training and control measures, which the trust subsequently addressed
