An ammonia leak in a B.C. arena that killed three workers is being blamed on a unique incident.
The system failure at the Fernie Memorial Arena on Oct. 17 is believed to be the first of its kind. Ammonia leaked into a secondary coolant – in this case brine – pressurizing the system. When a coupling in the brine piping separated there was a rapid release of ammonia into the enclosed room where the three men were working, states the investigation report, by Technical Safety BC (TSBC). The leak also resulted in the evacuation of 95 residents from 55 nearby homes.
TSBC has made 18 recommendations to further improve safety in ice rink refrigeration systems and, at a press conference July 25, discussed several regulatory actions taken in recent months to prevent similar incidents.
“Since the incident occurred last year, Technical Safety BC has taken decisive action to advance the safety of ammonia refrigeration facilities in the province. We issued a province-wide Safety Order requiring all public occupancy ammonia refrigeration plants – including arenas – to test for ammonia leaks and shut down the system if necessary. All 185 facilities in British Columbia have fulfilled the obligation and are compliant,” said Janice Lee, director of safety oversight at TSBC.
The eight-month investigation explored pre-incident and post-incident factors that may have contributed to the ammonia leak. TSBC analyzed equipment and its condition and reviewed inspection reports and the results of systems testing. The team also examined relevant organizational and operational decisions that may have contributed to the incident, and inspected and tested the alarm, ventilation and discharge systems.
The investigation identified three areas that contributed to the incident and the impact to the arena and surrounding community:
- Failure of refrigeration system equipment;
- Operational decisions; and,
- Impact of inadequate ventilation and discharge systems following the incident.
However, the ammonia leak resulted from practices that were common in the industry at the time, the investigation found.
“It is imperative that industry and owners of refrigeration systems learn a number of lessons from this incident, but two in particular stand out,” said Jeff Coleman, TSBC director of risk and safety knowledge with and leader of the investigation team. “First, maintenance programs for refrigeration systems must address and alleviate the risks presented by ageing equipment. And second, even very small leaks of refrigerant can indicate extremely hazardous situations.”
TSBC recommendations to prevent a recurrence and improve safety in ice rink refrigeration systems include:
- Owner maintenance programs, especially in relation to ageing equipment;
- Identification of leak hazards and professional disclosure of such hazards;
- Training of owners’ representatives, operators and mechanics; and,
- Better secondary coolant system configuration and construction.
“This has been a terrible loss for the families of the three workers and had a deep impact on the whole community of Fernie,” said Quinn Newcomb, TSBC interim vice president of human resources, learning and engagement. “We will work with stakeholders to enhance the safety system to prevent a similar tragedy from ever happening again.
“Technical Safety BC believes safety is a shared responsibility and will take a leadership role in meeting with stakeholder groups including plant owners, maintenance contractors, training providers, municipalities, and the Canadian Standards Association to present and discuss the recommendations and improve facility maintenance procedures and programs,” added Newcomb.
The full report is available at: https://www.technicalsafetybc.ca/fernieincident.