NNSL (Jan 10/97) - Gordon Wray and his family woke up Friday, their nostrils lined with blood and soot, and sick from carbon monoxide gas that had leaked into their home.

"Covered in soot, the (white) dog was the best indicator of all," Wray said. "His ears and tail were black."

The Wray family had experienced the early stages of carbon monoxide poisoning last week. An invisible, tasteless and odorless gas, carbon monoxide can kill at high concentrations.

"We feel very lucky, particularly because everyone was home for the holidays," he said.

Ice build-up on the Wrays' chimney forced the inner liner to collapse. Moisture from the ice seeped down into the liner and caused it to compress and eventually cave in, forcing the poisonous gases back into the home.

Not uncommon in cold climates, the problem keeps the Yellowknife Fire Department busy during the winter months inspecting chimneys for ice build-up, said Mike Lowing, deputy fire chief.

The city's fire department has been particularly busy this month, completing more than 40 inspections since Jan. 1.

Lowing said people should watch for ice on their chimney and check their chimney liners regularly. The liners should be round and smooth.

"They (Wrays) are very lucky," he said. "Our concern is that there are other homes in the same state."

Lowing said that if people suspect their home may have dangerous levels of carbon monoxide, they can call the fire department 24 hours a day for an inspection.

Such an inspection -- or a carbon monoxide detector -- may save a family from poisoning.

Despite regular maintenance and cleaning, the Wray chimney still failed under the pressure of cold temperatures.

"This has made me realize that no matter how well you maintain your chimney, you've still got to keep an eye on it," said Wray.

"It can happen to anyone," he added. "It's so hard to detect."

Immediately after this incident, Wray bought a carbon monoxide detector that will trigger an alarm if a dangerous level of gas is present. The detector sells in Yellowknife for $50 to $80.

"Mine cost $80, and at $10 a head, I figure it's worth it," said Wray.

The cost is minor, he said, compared with the lives of his family and the thousands it will cost him to repair the damage in his home.

Ceilings have to be repainted, walls cleaned, carpets cleaned, clothes dry-cleaned, and electronic equipment checked.

"People should put in a carbon monoxide detector," he said. "It could save your life."