OHS Canada Magazine

Carbon-monoxide leak sends four airport employees to hospital

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November 1, 2016
By Jeff Cottrill

Compliance & Enforcement Hazmat Health & Safety Transportation carbon monoxide gas leak Health and Wellness newfoundland newfoundland and labrador occupational health and safety St. John's

Two exposures in building within a week

(Canadian OH&S News) — Four workers at St. John’s International Airport in St. John’s, N.L. were taken to a hospital on Oct. 26, after being exposed to carbon monoxide (CO) in a terminal building. The leak was the second such incident in the building in less than a week.

A media statement from the St. John’s International Airport Authority (SJIAA) confirmed that both incidents had occurred in a non-public area in the east end of the building, where construction was taking place.

The first CO leak happened on Oct. 21 and was reported to the SJIAA on the following day. After the second incident on the 26th, occupational health and safety representatives from Employment and Social Development Canada (ESDC) issued a stop-work order regarding all construction activities using gas-powered vehicles and equipment.

“This stop-work order will continue until the incident is further investigated to confirm cause,” the SJIAA said.

Local media reports have stated that the employees who were sent to the hospital were security staff, but the SJIAA did not confirm this.


Following the initial leak, the SJIAA installed additional gas-monitoring systems, sampled the air quality with continual spot checks and inspected the building’s air-handling units. Following the second incident, the air quality in the area was tested again, “with minimal-to-zero carbon-monoxide readings detected,” the statement read.

“The Airport Authority is fully committed to identifying and eliminating the sources that may have contributed to these incidents,” the SJIAA continued. “All construction contractors are engaged in the investigation process and are identifying and putting in place mitigation measures to prevent such incidents from occurring.”

ESDC media spokesperson Amélie Caron confirmed to COHSN that the federal labour ministry is investigating the incidents. The SJIAA stated that it was cooperating fully with the investigation.

While Service N.L. investigates most oh&s incidents that occur in Newfoundland and Labrador, the St. John’s airport falls under the jurisdiction of the federal government, as do all airports in Canada, according to Section 2(e) of the Canada Labour Code.

“The Airport Authority will continue to diligently monitor and conduct air-quality surveys regularly,” said the SJIAA, “with the assistance of an industrial hygienist, and ensure all contributing factors have been mitigated.”

CO is a colourless, odourless and highly flammable gas that can be fatal if a worker inhales it. According to the Canadian Centre of Occupational Health and Safety (CCOHS) in Hamilton, Ont., CO is also capable of damaging blood, causing frostbite and harming unborn children.

CCOHS advises immediate evacuation of any area where CO has been accidentally released, among other tips for workers on its website. “Keep out unnecessary and unprotected personnel,” it adds. “Use personal protective equipment as required. Eliminate all ignition sources. Use grounded, explosion-proof equipment. Vapour or gas may accumulate in hazardous amounts in low-lying areas especially inside confined spaces, if ventilation is not sufficient.”

Regarding containment and cleanup, employees should ventilate the contaminated area, especially confined spaces, to keep the CO from accumulating. “Stop or reduce leak if safe to do so,” CCOHS says. “Knock down gas with fog or fine water spray. Dike and recover contaminated water for appropriate disposal.


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