The inspections and stickers are necessary due to the changing composition of gas supplies entering Questar Gas's system. Changing gas composition is the result of several factors, the most significant being the discovery of a huge natural gas field near Price, Utah.

"This new discovery is important because it provides a reliable, economical supply source right in our own backyard," said Nick Rose, Questar Gas president and CEO. "While these supplies meet all local and national quality and safety standards, their composition is different from the supplies we have delivered in the past."

Questar Gas is currently able to process these new supplies or blend them with other natural gas sources to create a mixture that is safe to use in all appliances. While the company believes it can successfully continue this practice for several years, it is unknown at this time exactly how long it will be able to do so and at the same time ensure deliveries at the lowest possible price. Once this transition period ends, appliances not properly adjusted will not be safe to use.

Rose emphasized that the transition does not require replacement of any appliances and affects only natural gas furnaces and water heaters. Operation of furnaces and water heaters that have not been properly adjusted once the transition period ends may result in the production of excess carbon monoxide, he added. Without proper ventilation, carbon monoxide can cause serious injury or death.

"Properly adjusted appliances are not only safer, they can cost less to operate. They also allow Questar Gas the flexibility to deliver with confidence the most economical supplies available," Rose said.

While Questar Gas expects the transition period to last several years, the company is strongly urging customers to act now by making sure their appliances have green stickers. The company is also asking manufacturers, installers and contractors to put green stickers on appliances that have been properly adjusted.

"An appliance that has been recently installed, repaired or inspected may already have been checked and adjusted," said Rose. "If so, it should have a green sticker. If a furnace or water heater doesn't have a green sticker, it should be checked by a licensed heating professional. At that point, the customer should insist that the contractor apply the green sticker for future reference."

Questar Gas customers in Wyoming and in the Utah communities of Vernal, Maeser, Naples, Roosevelt, Moab, Monticello, Huntington, Castle Dale, Orangeville, Ferron, Clawson, Elmo and Cleveland should have appliances that are already properly adjusted for the gas supplies in those areas. However, to ensure safe operation and maximum efficiency and performance, Questar Gas recommends that all customers have their furnaces periodically maintained by a licensed contractor who can check to make sure their equipment is properly adjusted.

The inspection and possible adjustment take about one to two hours to perform and involve checking and, if necessary, changing an orifice that governs the mixture of air and natural gas needed for proper and complete fuel combustion. Contractor rates can vary depending on the type and number of appliances inspected and whether or not an adjustment is needed.

"Our primary concern is customer safety," Rose said. "We want our customers to be aware of this issue and the steps they need to take to make sure their appliances are set for proper and efficient operation."