From news.com.au;
"IT HAS no modus operandi. It’s indiscriminate, and it strikes when you least expect.
Carbon monoxide is a silent, odourless and toxic gas that once unleashed can render a person unconscious in an instant, and take their life within minutes.
It is believed this invisible killer claimed the lives of a young Sydney couple as they holidayed in the Blue Mountains at the weekend.
The pair had been staying in a makeshift cabin overlooking Days Gulley and had used a wood chip heater to keep warm as temperatures dropped overnight.
The tragedy has been a painful reminder for Vanessa Robinson, who lost her two sons to the silent killer just over five years ago.
Chase, 8, and Tyler, 6, were sleeping with their mother in her bed when they inhaled the deadly fumes from a leaking gas heater in their Victorian home in 2010.
Ms Robinson told news.com.au that every time she heard of another carbon monoxide death, she was reminded of what she lost, and also how preventable the latest deaths could have been.
“Sometimes it still just hits me that I can’t believe that my children have died because of a gas heater,” she said. “It’s hard to wrap your head around."