The owner of a Delta farm where more than 40 people were exposed to carbon monoxide says his company is reviewing safety protocols in the wake of the scare.
All 42 patients who were exposed to the gas at Windset Farms on 41B Street on Saturday afternoon have since been treated and released.
At the time of the exposure, emergency officials said as many of 10 of them were taken to hospital in serious-to-critical condition.
Delta fire battalion chief Neil Shuster said the gas buildup was likely caused by poor ventilation of a gas-powered pressure washer that workers were using to clean the inside of the facility.
Windset farms co-owner John Newell said crews frequently use pressure washers to clean the greenhouses, but this is the first time something like this has happened.
“The entire roof of the greenhouse is many, many, many hundreds — if not more — windows that can open and close. And we just don’t know where they were set, if they were set not wide enough and open enough.”
The company is now reviewing its operating procedures, and will be updating protocols, including possibly adding carbon monoxide detectors, Newell said.
“We’re just thanking our lucky stars that… no one was seriously injured.”
Newell said WorkSafeBC is now investigating how many pressure washers were being used, where they were located and how many windows were open.
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While only a dozen workers showed symptoms of the exposure, BC Emergency Health Services (BCEHS) director of operations Samantha Wilbur said that first responders treated the incident as a mass casualty event.
Thirteen ambulances and a transit bus, which was used to keep people warm while they were being assessed, were dispatched to the site, she said.
She added that victims were sent to seven different hospitals for treatment.
“They were spread out to make sure we didn’t overwhelm one resource. And so it took some time to make sure that, first off, the patients were not critical,” she said.
“We wouldn’t delay any transports if we were really concerned about their outcomes.”
Wilbur added that when crews arrived they were unsure of exactly what kind of contamination they were dealing with, so they set up a staging and triage area well away from the greenhouses.
She said crews also worked to ensure that there was no chemical or biological contamination being transported to local hospitals.