Warning: This story contains a graphic images of frostbite.

Parents in Colville Lake, N.W.T., say they feel they're being blamed by the school board after four children developed frostbite during a school trip.

The trip happened about three months ago. Parents have been waiting for details about an investigation ever since, and say they finally heard an update Monday afternoon, three days after CBC News published an article on it.

Details on the investigation that have now been provided to the parents focused mainly on policy changes, including one that ensures all students going out on the land for a school trip have access to proper winter gear. If they don't, Jordan's Principle would provide gear.

Jennifer Lafferty's daughter, Pearl, was 10 at the time and needed to be flown to Norman Wells after the trip to have severe frostbite treated on her legs. Jennifer said her daughter was wearing proper gear — including a parka, snow pants and boots.

"[It's] making it sound like these kids weren't dressed properly," she said of the new policy.

Stephanie Orlias's daughter, Alicia, also had her ear frostbitten, but Stephanie said her daughter was wearing a big hat.

Renee Closs, the Sahtú Divisional Education Council superintendent outlined the policy changes during a call with parents on Monday.

Lafferty said the timing of the details coming so soon after the publicity was also frustrating.

During the call, parents asked Closs why they're getting these details so soon after CBC News published an article on the incident. Closs told them the investigation involved multiple levels of government, which delayed the process.

New policy, but no apology

Parents say they never got an apology for the incident.

Aside from making sure children are dressed properly, the new policy would prevent on-the-land trips from happening when it's below –25 C. It was below –30 C when the kids went out on Nov. 29.

Closs told parents school trips would now require them to sign a consent form to allow children to drive snowmobiles.

Jennifer and Stephanie said they weren't happy their children were made to drive themselves on the trip, and doing so is what resulted in frostbite. They said the children should have been riding in a sled, behind the snowmobile, which offers more protection from the wind.

The parents said no details were given on whether there would be any disciplinary measures for the teacher who organized the trip.

CBC News reached out to Closs to confirm the details of the investigation on Monday evening.

On Tuesday, she responded by email to say the changes have been recommended, but the school board still needs to approve them which will not be until the end of March or early April. Closs did not agree to an interview.

CBC News reached out to R.J. Simpson, the N.W.T.'s education minister, on Feb. 24 for an interview about the incident, but was told he would not be available as the matter is being handled by the school board.

Tissue damage

CBC News reached out to the N.W.T.'s health department several times for a medical expert to talk about frostbite. David Maguire, a spokesperson for the health authority, declined the request.

Dr. Anthony Fong, a clinical assistant professor at the University of British Columbia who is also a family and emergency physician, said frostbite — similar to burns — has four degrees of severity.

There is first-degree, comparable to a mild sunburn; second-degree, which involves painful blistering and peeling skin; third-degree, which are deeper blisters that can fill with blood; and finally fourth-degree, which affects deeper tissues like bone or muscles and can require amputation.

Looking at a photo or Pearl's frostbite, Fong said it would be a case of at least second-degree frostbite, depending on how deep the blisters were.

He said frostbite is ultimately tissue damage, meaning the more serious it is, the worse the skin can be left. In Pearl's case, Jennifer said there is still scarring on her legs.

The children on the trip developed frostbite while travelling out to the camp, and spent the night before coming back. Fong said there are some dangers to remaining in a cold environment after experiencing frostbite.

"There's also this phenomenon of rewarming, then being exposed to cold again, which is extra damaging to tissue," he said.

"If my foot is really cold and then I rewarm it in a camp, then I go out the next day on a snowmobile and it gets cold again," Fong said, this is more "damaging than just getting cold and then reheating once."