{
  "id": "protocols:tower-lookup",
  "collection": "protocols",
  "slug": "tower-lookup",
  "name": "Identifying a nearby tower from public records",
  "summary": "How to establish what is actually on a mast — height, azimuth, licensee — from the FCC Antenna Structure Registration and licence databases before estimating exposure.",
  "status": "verified",
  "lastVerified": "2026-08-12",
  "data": {
    "aliases": [
      "find cell tower near me",
      "ASR lookup"
    ],
    "goal": "Replace assumptions about a nearby structure with its registered parameters, which change any exposure estimate by orders of magnitude.",
    "quantity": "power-density",
    "equipment": [
      "broadband-rf-meter",
      "directional-antenna"
    ],
    "steps": [
      "Search the FCC Antenna Structure Registration database by location to find registered structures and their coordinates and heights.",
      "Cross-reference the licence records for the structure to identify licensees, services and authorised parameters.",
      "Compute the geometry: horizontal distance, height difference, and the elevation angle from the dwelling to the antenna.",
      "Compare that angle with typical sector downtilt to judge whether the dwelling is in the main beam, a sidelobe, or below the pattern.",
      "Measure indoors and outdoors with a directional antenna to confirm the bearing matches the structure before attributing any reading to it."
    ],
    "pitfalls": [
      "Assuming the closest structure is the dominant source; a farther tower on boresight often is",
      "Ignoring that structures below the registration height threshold, and many rooftop and small-cell installations, do not appear in ASR at all",
      "Estimating from EIRP alone without antenna pattern, which overstates ground-level exposure at the tower base substantially"
    ],
    "interpretAgainst": [
      "limits:fcc-mpe-public-300-1500",
      "limits:ch-onir-installation-mobile"
    ],
    "related": [
      "emitters:macro-cell-tower",
      "questions:how-far-should-i-live-from-a-cell-tower"
    ]
  },
  "sources": [
    {
      "id": "fcc-asr",
      "title": "Antenna Structure Registration (ASR) public access database downloads",
      "publisher": "Federal Communications Commission",
      "url": "https://www.fcc.gov/wireless/data/public-access-files-database-downloads",
      "kind": "government",
      "retrieved": "2026-08-12"
    },
    {
      "id": "fcc-oet65",
      "title": "OET Bulletin 65: Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields",
      "publisher": "Federal Communications Commission, Office of Engineering and Technology",
      "url": "https://www.fcc.gov/general/oet-bulletins-line",
      "year": 1997,
      "kind": "government",
      "retrieved": "2026-08-12"
    }
  ],
  "links": {
    "self": "https://emfbase.com/api/protocols/tower-lookup",
    "html": "https://emfbase.com/protocols/tower-lookup",
    "markdown": "https://emfbase.com/protocols/tower-lookup.md",
    "collection": "https://emfbase.com/api/protocols"
  }
}