Your home should have carbon monoxide detectors outside sleeping rooms and in the space or hall directly adjacent to the sleeping room. In addition, at least one CO detector should be located on every floor of the home. Please download and review the carbon monoxide summary sheet from the NFPA, who is regarded as the authority on safety topics.
http://www.nfpa.org/~/media/files/safety-information/safety-tip-sheets/cosafety.pdf?la=en
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