Not everyone needs a residential carbon monoxide detector. You should consider installing one if you live in a house, townhouse, or an apartment with:
liquid-fueled space heaters (kerosene or propane
an attached garage
gas appliances (furnace, stove, fireplace, clothes dryer,or hot water heater)
oil heat
a wood stove
Also, consider a CO detector for your recreational vehicle.
If you live in an all-electric single family residence without any combustion-type appliances or an attached garage, you may not need a residential CO detector
1. Do You Need a Carbon Monoxide Detector?
First, do you need a carbon monoxide detector? If you use electricity to heat your home and cook all your meals, you may not need one. But there are other situations that can present a danger. Read this article from Pediatrics Guide Vincent Iannelli to find out more and learn if you should have a carbon monoxide detector in your home and find out more about the dangers of this colorless, odorless gas.
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2. Purchasing a Carbon Monoxide Detector
If you found that your home needed a carbon monoxide detector, then selecting and purchasing one is the first step in protecting your family. The detector should be listed by an independent testing laboratory, such as UL, ETL, CSA or another lab. Here are five picks from Lung Diseases Guide Stacey Lloyd that fit the bill. Once you have your detector install it near sleeping areas, but do not place it near fuel burning appliances as it could give an inaccurate reading and trigger false alarms.
Top Picks
3. Use Gas Appliances Properly
If you have a gas range or oven, don't try to use it to heat your home, for instance. According to the California Environmental Protection Agency, these appliances pose more than just a carbon monoxide poisoning risk. They also produce dangerous levels of nitrogen dioxide, which can cause respiratory disease. The danger here is especially high for young children. Always follow the manufacturer's guidelines for use.
4. Never Use a Charcoal Grill Indoors
The amount of carbon monoxide put out by grills is very high. Even using one of these too close to an open window can be a danger. Follow these safety tips for safe grilling.
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5. Have Your Heating System Serviced
Each year before you fire up the furnace for the first time, have a qualified service technician perform an inspection. If anything needs to be repaired, have it done immediately so that you're not left cold, or worse -- left using a system that could pose a poisoning hazard. Potential issues include cracks in vents, buildup on burners and improper installation.
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6. Have Chimneys and Flues Cleaned
Improperly maintained chimneys and flues can crack and have buildup that causes issues with venting. The carbon monoxide that is supposed to be going out can then come right into your home. Even if carbon monoxide isn't a problem, not taking care of your fireplace can be a hazard in other ways. Creosote buildup is a major cause of flue fires each year.
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7. Make Sure Your Wood Stove Meets Fire Codes
Building and fire codes vary greatly from city to city and country to country. The best way to find this information is to go directly to the source. Call your local fire marshall or other official in charge of fire protection and ask whether your unit needs to be inspected in person and what the code is for your area.
8. Open Chimney Dampers Before Using Fireplaces
You need oxygen to breathe, and so does your fire. By opening the damper, you create a draft that goes up the chimney. This will give your fire air to burn efficiently and also provide ventilation of smoke and carbon monoxide.
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9. Make Sure New Heating Appliances Are Tested by Independent Labs
You've seen it before -- that little UL sticker or stamp on products ranging from TVs to electric blankets. Make sure there's one on any new space heater or other appliances you buy as well. It doesn't have to be UL, there are other labs. But they all have rigorous evaluation standards and these organizations are not affiliated with the manufacturer so the results won't be biased.
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10. Use Kerosene Heaters Properly and Keep Them Inspected and Maintained
Use these heaters with the proper fuel (follow manufacturer's guidelines) and make sure that you are using the proper ventilation. In addition, wait until the unit has cooled down completely before you re-fuel it. Never re-fuel indoors.
We bought one that is not "installed". It just sit's on top of our 'fridge. We check it each day to make sure the battery is still good. I don't think we paid more than $30 for it.
to some Maryland people. 
