GAS emergency engineers are asking people to be very nosey over Christmas.

The company is urging anyone who smells gas inside or out to report it immediately.

"Transco's first priority is safety and our engineers will respond to calls whenever and wherever they are made," said north area emergency services manager Steve Adair.

The service is free and engineers work around the clock every day to ensure it is always available.

People are also being warned to ensure gas appliances are installed and maintained properly to reduce the risk of carbon monoxide poisoning.

Children and older people are most at risk because carbon monoxide is tasteless and does not smell.

Symptoms of poisoning also resemble winter colds and flu such as headaches, stomach pains and fatigue.

Warning signs to look for include stains or discolouring around a gas fire, water heater or boiler, an appliance burning with a yellow or orange flame when it should be blue, or condensation in a room where an appliance is installed.

* The free 24-hour gas emergency number is 0800 111 999.