HALIFAX — Inadequate ventilation, poor maintenance and old equipment are being blamed for causing a buildup of potentially hazardous airborne mould aboard Canada’s most advanced warships, newly released Defence Department documents show.
However, the military officer in charge of naval engineering says most of those problems have been fixed, and he insisted the health of sailors is not being put at risk.
“We are taking the health and welfare of our sailors as our top priority,” Commodore Simon Page said in an interview Friday. “We are very responsive in addressing issues.”
The department’s Directorate of Force Health Protection says an air quality assessment aboard HMCS Winnipeg found higher-than-normal levels of mould spores in three compartments while the frigate was sailing from Tokyo to Hawaii in July 2017.
A report from March 2015 — prepared by the engineering firm Bronswerk — found the frigates’ ventilation and air conditioning systems had “significantly degraded” because of a lack of maintenance, leaving the equipment “old and unsupportable.”
The findings are important because some sailors have long complained of health problems they say could be related to mould exposure while serving aboard Canada’s 12 Halifax-class frigates. Commissioned in the early to mid-1990s, the Canadian-built warships typically carry a crew of about 200.
Airborne mould concentrations aboard Winnipeg were found to be above background levels in an air conditioning plant, the ship’s solid-waste handling plant and an equipment room near the helicopter landing pad. High levels of humidity were also recorded in all three locations.
Page, the navy’s director general of maritime equipment, said the mould problem was minor.
“We had a very small amount of mould in four compartments,” he said. “I would not qualify this as a mould problem. And three of these four compartments are not manned.”
When asked about the potential for the air conditioning system to spread mould throughout the ship, Page said there was a quick fix for that.
“For that problem, we were very aggressive with the issue,” he said, adding that all 12 ships have been modified to prevent water buildup in the air conditioning system. ”It was one of those engineering changes that was effected promptly.”
The navy first learned of mould problems in its frigates in 2011 as the ships were being prepared for a thorough modernization process that concluded in 2016, he said.
Some upgrades to the ships’ heating, ventilation and air conditioning systems have yet to be completed, Page said.
In all, 20 of Winnipeg’s compartments showed some accumulation of dust or mould.
While there are no standard exposure limits for airborne concentrations of mould or mould spores, the December 2017 air quality assessment says mould is hazardous for people with compromised immune systems or mould allergies.
The Royal Canadian Navy should improve the ships’ ventilation and require more frequent cleaning and inspections of ducts and filters, the report says.
Aside from airborne mould, the 2017 assessment also found mould growing on some surfaces, though the report noted that undisturbed surface mould is generally not a problem.
The report includes photos showing mould on insulated pipes inside an air conditioning system, at a duct joint in the crew’s lounge washroom, above the fan in the fruit and vegetable store, and on beams in the ceiling in the potato locker. Yeast was also found growing on a bulkhead near the wardroom.