Sedona, AZ – Eight members of a Sedona family are recovering from carbon monoxide poisoning because of gas leaking from the furnace.

Units from the Sedona Fire District were called to the family’s home shortly after 9:30 Monday morning.

An adult male was experiencing nausea and lightheadedness.

“During questioning of additional family members, SFD Captain Brian Ford quickly realized that there may be a potentially dangerous accumulation of carbon monoxide (CO) inside of the home,” according to a news released from the agency.

A gas monitor confirmed Ford’s suspicions, showing high levels of carbon monoxide throughout the house, particularly near the furnace and adjacent bedrooms.

Five people were taken to Verde Valley Medical Center. Two children who had been picked up for school were transported, as well.

Carbon monoxide is a colorless, odorless gas that can be deadly.

The Centers for Disease Control and Prevention recommends people equip their homes with carbon monoxide detectors to protect themselves.

A spokesman for the Sedona Fire District said such detectors could have been useful this situation, alerting the family to the danger before they got sick.

“Having a working CO alarm in the home is a critical step in early detection. With the recent cold weather, people are turning on their heaters and need to protect their family” SFD Fire InspectorRick Evans said. “It is also a good time to have furnaces and other gas appliances checked by a qualified technician for proper operation.”

“CO is found in fumes produced any time you burn fuel in cars or trucks, small engines, stoves, lanterns, grills, fireplaces, gas ranges, or furnaces,” according to the CDC’s FAQ page. “CO can build up indoors and poison people and animals who breathe it.”

In early April, a San Tan Valley Family was treated for carbon monoxide poisoning after a woman accidentally left her car running in their garage overnight. A couple of weeks later, the same thing happened to two Scottsdale residents and their dog.

Later that month, carbon monoxide detector saved the lives of a Peoria family.

Last December, a Phoenix family fell victim to carbon monoxide poisoning after the father took a charcoal grill inside to heat the home.

CO poisoning can sneak up on you, which is why having a detector is so important. Symptoms, often described as “flu-like,” can be mild at the outset, but escalate quickly. Carbon monoxide is often referred to as a silent killer.

“If you breathe in a lot of CO it can make you pass out or kill you. People who are sleeping or drunk can die from CO poisoning before they have symptoms,” according to the CDC.

Although CO poisoning does not discriminate, infants, the elderly and people with chronic heart disease, anemia or breathing issues are most susceptible.

Symptoms of CO poisoning

Headache

Dizziness

Weakness

Upset stomach

Vomiting

Chest pain

Confusion

If you are feeling these symptoms and think you have been exposed to CO, get to fresh air, turn off any fuel-burning appliances and dial 911.

According to the CDC, more 400 Americans die each year from unintentional CO poisoning not linked to fires. More than 20,000 visit the emergency room, and more than 4,000 are hospitalized.

CDC: How can I prevent CO poisoning in my home?

→ Install a battery-operated or battery back-up CO detector in your home and check or replace the battery when you change the time on your clocks each spring and fall. Place your detector where it will wake you up if it alarms, such as outside your bedroom. Consider buying a detector with a digital readout. This detector can tell you the highest level of CO concentration in your home in addition to alarming. Replace your CO detector every five years.

→ Have your heating system, water heater, and any other gas, oil, or coal burning appliances serviced by a qualified technician every year.

→ Do not use portable flameless chemical heaters indoors.

→ If you smell an odor from your gas refrigerator have an expert service it. An odor from your gas refrigerator can mean it could be leaking CO.

→ When you buy gas equipment, buy only equipment carrying the seal of a national testing agency, such as Underwriters’ Laboratories.

→ Make sure your gas appliances are vented properly. Horizontal vent pipes for appliances, such as a water heater, should go up slightly as they go toward outdoors, as shown below. This prevents CO from leaking if the joints or pipes aren’t fitted tightly.

→ Have your chimney checked or cleaned every year. Chimneys can be blocked by debris. This can cause CO to build up inside your home or cabin.

→ Never patch a vent pipe with tape, gum, or something else. This kind of patch can make CO build up in your home, cabin, or camper.

→ Never use a gas range or oven for heating. Using a gas range or oven for heating can cause a build up of CO inside your home, cabin, or camper.

→ Never burn charcoal indoors. Burning charcoal – red, gray, black, or white – gives off CO.

→ Never use a portable gas camp stove indoors. Using a gas camp stove indoors can cause CO to build up inside your home, cabin, or camper.

→ Never use a generator inside your home, basement, or garage or less than 20 feet from any window, door, or vent.