{
  "id": "quantities:frequency",
  "collection": "quantities",
  "slug": "frequency",
  "name": "Frequency",
  "summary": "Cycles per second, the axis that determines which limit applies, which meter can see the signal, and which shielding works.",
  "status": "verified",
  "lastVerified": "2026-08-12",
  "data": {
    "aliases": [
      "Hz",
      "GHz",
      "MHz"
    ],
    "quantityId": "frequency",
    "symbol": "f",
    "siUnit": "Hz",
    "units": [
      {
        "symbol": "Hz",
        "name": "hertz",
        "toBase": 1
      },
      {
        "symbol": "kHz",
        "name": "kilohertz",
        "toBase": 1000
      },
      {
        "symbol": "MHz",
        "name": "megahertz",
        "toBase": 1000000
      },
      {
        "symbol": "GHz",
        "name": "gigahertz",
        "toBase": 1000000000
      }
    ],
    "measures": "Signal repetition rate. EMF work splits at roughly 100 kHz: below it, effects and limits are about nerve stimulation and fields are treated as electric and magnetic separately; above it, limits are about energy absorption and the two components are linked."
  },
  "sources": [
    {
      "id": "nist-si",
      "title": "The International System of Units (SI), NIST Special Publication 330",
      "publisher": "National Institute of Standards and Technology",
      "url": "https://www.nist.gov/pml/special-publication-330",
      "kind": "government",
      "retrieved": "2026-08-12"
    },
    {
      "id": "icnirp-2020",
      "title": "Guidelines for Limiting Exposure to Electromagnetic Fields (100 kHz to 300 GHz)",
      "publisher": "International Commission on Non-Ionizing Radiation Protection",
      "url": "https://www.icnirp.org/en/publications/article/rf-guidelines-2020.html",
      "year": 2020,
      "kind": "guideline",
      "retrieved": "2026-08-12"
    }
  ],
  "links": {
    "self": "https://emfbase.com/api/quantities/frequency",
    "html": "https://emfbase.com/quantities/frequency",
    "markdown": "https://emfbase.com/quantities/frequency.md",
    "collection": "https://emfbase.com/api/quantities"
  }
}