There have been 10 shipboard fires or smoke incidents aboard Canada's fleet of front-line frigates over the last two years, according to recently released Department of National Defence summaries and statistics.

The commander of the navy, Vice-Admiral Art McDonald, said the episodes were minor — but they also serve as a stark reminder that the warships, built in the 1990s, are now in the second half of their operational lifespans and will require more attention and upkeep.

"Fire is one of the greatest enemies to ships at sea, or alongside [the dock] in the water," said McDonald, whose staff released a summary of incident reports following an interview with CBC News.

A defence expert went even further and said the string of fires should put heat on the Liberal government to keep the long-planned, often-delayed frigate replacement program on track.

Vice-Admiral Art McDonald, commander of the Royal Canadian Navy, said 10 navy frigates have faced fires and smoke incidents over the last two years. He described the events as minor but said they are a reminder that the warships are in the second half of the lives. (Murray Brewster/CBC)

Only a handful of the fires were reported publicly. McDonald was asked about them after CBC News collected a series of anecdotal reports from individual sailors about instances that had gone unreported.

'Different sources, different locations'

The summaries reveal one of the warships, HMCS Regina, experienced multiple fires — two in the fall of 2018 and another in the spring of 2019 — while conducting "at-sea readiness training in preparation for an upcoming deployment to the Asia Pacific."

The same warship suffered a fourth "smoke incident" last fall when a faulty transformer in a forward electrical switchboard began to smoulder.

HMCS Calgary and HMCS Toronto experienced two fires each over that two-year period, all of which rated public mentions at the time.

HMCS Halifax, the oldest frigate in the fleet, also suffered two fires; the more significant one broke out in the engine room during the fall of 2018 while the frigate was participating in the NATO exercise Trident Juncture.

In releasing the summary, navy Capt. Jason Armstrong, the chief of staff to the commander, said only two of the incidents resulted in injuries to crew members — minor ones, "including lacerations, bruises and smoke exposure."

One of those incidents happened aboard HMCS Calgary in December of last year, off San Diego. "A few members" were injured and "placed under observation for smoke exposure," according to the summary. The summary does not describe the other incident involving minor injuries.

Perhaps the most troubling incident was one of the two fires reported aboard HMCS Toronto. It happened on Aug. 21, 2019, while the ship was alongside the jetty in Halifax.

Smoke could be seen coming from HMCS Toronto while it was alongside the jetty in Halifax in August 2019. (Submitted photo)

"This investigation was unable to identify a clear cause for the fire, as the source of ignition could not be confirmed, and no evidence of an electrical short could be found," Armstrong wrote in the summary. "A follow-on technical investigation is underway to identify if any technical circumstances may have contributed to the events."

McDonald said the causes of the other fires were all identified, and the navy is confident it does not have a "systematic" issue on its hands.

"They are different sources, different locations," he said.

"There's the gamut. Fires happen. We're prepared for them. But especially in the second half of life for vessels, you want to make sure we are taking extra time; we're giving it the extra attention it deserves and there's nothing systematic in there we need to address."

High-level firefighting training is conducted both individually and at a team level throughout the navy, McDonald added.

The history of naval fires

That expertise was on display in February 2014 during the almost catastrophic engine room fire aboard the navy's last supply ship, HMCS Protecteur, which occurred in the waters off Hawaii. The blaze and subsequent damage led to the replenishment ship's early retirement from the fleet.

A follow-up investigation, known as a board of inquiry, found that 82 per cent of the crew were up-to-date in terms of firefighting and first aid training. The final report, obtained by CBC News under access to information legislation, concluded the initial response to the fire was "inconsistent" but the blaze was extinguished with no loss of life.

In 2004, the navy suffered a more substantial blow when the newly acquired, British-built, second-hand submarine HMCS Chicoutimi was ravaged by an electrical fire in North Atlantic while on its maiden voyage to Canada. One sailor, Lt. Chris Saunders, died of smoke inhalation.

Frigates 'starting to get pretty long in the tooth'

Rob Huebert, a defence expert at the University of Calgary, said all warships are inherently dangerous places to work and fires have the potential to "kill real quick," especially at sea.

"A lot of the fires will start real small, but the problem is they get big real fast" in that kind of heavy machinery setting, he said.

Sailors are well-trained and "super, super sensitive" to the potential danger, Huebert added.

He said he's comforted to know the navy has found no systematic issues, but said the real lesson from this disturbing trend should be for the federal government and senior decision-makers, who are in the process of laying down the design for the warships that will replace the frigates.

The replacements are due to begin arriving in the mid-2020s. Huebert said the fire incidents illustrate the importance of moving the project along.

The frigates "are starting to get pretty long in the tooth. They are by no means obsolete, but you will not be able to push off their replacement" the way successive governments have done with fighter jets, he said. "We cannot lag on this one."