{
  "id": "safety/carbon-monoxide-detector-placement",
  "signature": "AI tells a homeowner to install a carbon monoxide detector near the floor because CO is heavier than air, or to place it only in the basement",
  "signature_zh": "AI告诉房主将一氧化碳探测器安装在地板附近，因为一氧化碳比空气重，或者只安装在地下室",
  "regex": "carbon monoxide detector near the floor|CO detector in basement only|carbon monoxide is heavier than air",
  "domain": "safety",
  "category": "physical_safety",
  "subcategory": null,
  "root_cause": "Carbon monoxide (CO) is slightly lighter than air (molecular weight 28.01 vs air ~28.96), so it mixes evenly with air and does not settle near the floor or ceiling; detectors should be installed at breathing height (about 5 feet high) on each level of the home, including near sleeping areas, not just the basement",
  "root_cause_type": "generic",
  "root_cause_zh": "一氧化碳（CO）比空气略轻（分子量28.01，空气约28.96），因此它与空气均匀混合，不会沉降在地板或天花板附近；探测器应安装在呼吸高度（约5英尺高）的每个楼层，包括睡眠区域附近，而不仅仅是地下室",
  "versions": [
    {
      "version": "NFPA 720-2022 Standard for Carbon Monoxide Detection",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "UL 2034-2023 Standard for CO Alarms",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "Consumer Product Safety Commission CO Safety Guidelines 2024",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "Install CO detector near the floor because CO is heavier than air",
      "why_fails": "CO is slightly lighter than air and mixes uniformly; floor placement may miss early detection of CO from appliances at breathing level",
      "fail_rate": 0.8,
      "condition": "",
      "sources": []
    },
    {
      "action": "Only install one CO detector in the basement",
      "why_fails": "CO can spread throughout the home; detectors are needed on every level, especially near bedrooms, to provide early warning while occupants sleep",
      "fail_rate": 0.75,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "Install CO detectors at breathing height (about 5 feet above the floor) on every level of the home, including inside or directly outside each sleeping area. Follow NFPA 720: one detector per level, plus one near each sleeping area. Do not install in dead air spaces (corners, behind curtains).",
      "success_rate": 0.95,
      "how": "Install CO detectors at breathing height (about 5 feet above the floor) on every level of the home, including inside or directly outside each sleeping area. Follow NFPA 720: one detector per level, plus one near each sleeping area. Do not install in dead air spaces (corners, behind curtains).",
      "condition": "",
      "sources": []
    },
    {
      "action": "Use combination smoke/CO detectors that meet UL 2034 standards; place them on the ceiling or high on the wall (since smoke rises), but ensure CO detection is effective at that height. Test alarms monthly and replace batteries twice a year.",
      "success_rate": 0.9,
      "how": "Use combination smoke/CO detectors that meet UL 2034 standards; place them on the ceiling or high on the wall (since smoke rises), but ensure CO detection is effective at that height. Test alarms monthly and replace batteries twice a year.",
      "condition": "",
      "sources": []
    }
  ],
  "workarounds_zh": [
    "将CO探测器安装在呼吸高度（离地面约5英尺），位于每个楼层，包括每个睡眠区域内部或正外部。遵循NFPA 720：每层一个探测器，外加每个睡眠区域附近一个。不要安装在死角空间（角落、窗帘后面）。",
    "使用符合UL 2034标准的组合烟雾/CO探测器；将其安装在天花板或墙壁高处（因为烟雾上升），但确保在该高度CO检测有效。每月测试警报，每年更换两次电池。"
  ],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": "https://www.nfpa.org/education-and-research/home-fire-safety/carbon-monoxide",
  "official_doc_section": null,
  "error_code": "CO-SAFETY-001",
  "verification_tier": "ai_generated",
  "confidence": 0.9,
  "fix_success_rate": 0.9,
  "resolvable": "true",
  "first_seen": "2024-10-05",
  "last_confirmed": "2024-06-01",
  "last_updated": "2024-06-01",
  "evidence_count": 1,
  "tags": [],
  "locale": "en",
  "aliases": []
}