MA – CBS4 – A husband and wife were likely minutes from death after they were overcome by carbon monoxide fumes at their business in Waltham.

They survived because rescuers were able to trace their emergency cell phone call in time.

Bob and Helen Roy of Watertown suddely became sick Tuesday morning at their welding business. The fumes were coming from a forklift that was running in an unventilated area.

Bob Roy says he thought he was having a seizure and he had no idea that that the propane tank on the forklift was creating the clear and odorless fumes in their warehouse.

He and his wife were drifting in and out of consciousness, but they were able to call 9-1-1.

They stayed on the line until rescuers could trace the call and reach them.

The couple was rushed to the hospital, where they spent two-and-a-half hours in a decompression chamber.

They are still being treated at Massachusetts General Hospital.