{
  "meta": {
    "schema": "statbook-api/1",
    "release_version": "3.0.0",
    "compiled_at": "2026-09-21T00:00:00Z",
    "generated_at": "2026-09-28T09:07:46Z",
    "attribution": [
      "© Crown and database right. Derived from content available under the Open Government Licence v3.0 from legislation.gov.uk.",
      "Contains public sector information licensed under the Open Government Licence v3.0."
    ],
    "docs": "https://statbook.co.uk/docs/",
    "signing": {
      "scheme": "minisign",
      "public_key": "RWSPzbJEmAXVEvTqYZ8O9iHuOcOUii5lCNZM5t9bdoQh4ZnwKsxk/+bd",
      "key_id": "12D5059844B2CD8F",
      "verify": "https://statbook.co.uk/assurance/#verify"
    }
  },
  "figure": {
    "id": "employment.working_time.night_work_limit_hours",
    "name": "Night work: average hours limit",
    "category": "employment",
    "jurisdiction": "GB",
    "unit": "hours",
    "value_type": "count",
    "currency": null,
    "cadence": null,
    "source_type": "si",
    "si_probe": {
      "verdict": "SI-HOLDS",
      "provision": "regulation-6-1",
      "probed": "2026-09-11",
      "source_url": "https://www.legislation.gov.uk/uksi/1998/1833/data.xml",
      "content_hash": "sha256:58b694d5ca7d5648823b779df78034086ce291c8b991dbdf5732653e5f2a3647",
      "setter": "uksi/1998/1833",
      "setter_url": "https://www.legislation.gov.uk/uksi/1998/1833/made/data.xml",
      "setter_hash": "sha256:702d61bf3f06765266766b01fd082464b0d0750526f6a1d8019d63ab3a2c9c26",
      "setter_provision": "regulation-6-1",
      "f_note": null,
      "tokens": [
        "shall not exceed an average of eight hours for each 24 hours"
      ],
      "commentaries_c": [
        "key-0740bef4c3d180359f76a8b1f5590155",
        "key-4aab634356b76771e5b3ef535d65145f",
        "key-5206ba5b7b9a23882f0e37280f949412",
        "key-5f27458897999bc071d5478ff10ed37b",
        "key-7751932d39a664af6102211fde02040d",
        "key-798af878422181ff13217175477f458a",
        "key-854134037476af0958333ec50bf7a99e",
        "key-d6a4c3ece06c4edb145053474ed27e3d",
        "key-e068c7f53c80aece5f543fa6de231850",
        "key-e4aa1b9507321a375f24fb77664256e1"
      ],
      "expires": null
    },
    "values": [
      {
        "value": 8,
        "value_minor": null,
        "effective_from": "1998-10-01",
        "effective_to": null,
        "announcement_date": null,
        "enacted_date": null,
        "instrument_made": true,
        "terminal_kind": null,
        "status": "single_source_A",
        "sources": [
          {
            "role": "legislation",
            "citation": "https://www.legislation.gov.uk/uksi/1998/1833/made (SI 1998/1833 reg 6(1) as made: \"A night worker's normal hours of work in any reference period which is applicable in his case shall not exceed an average of eight hours for each 24 hours\"; in force 1 October 1998, reg 1(1))",
            "uri": "https://www.legislation.gov.uk/uksi/1998/1833/made",
            "retrieved": "2026-09-11T00:12:39Z",
            "content_hash": "sha256:702d61bf3f06765266766b01fd082464b0d0750526f6a1d8019d63ab3a2c9c26",
            "content_hash_of": "https://www.legislation.gov.uk/uksi/1998/1833/made/data.xml"
          }
        ],
        "verified": {
          "legislation": "2026-09-21T10:07:35Z"
        },
        "last_verified": "2026-09-21T10:07:35Z"
      }
    ],
    "derivation": null,
    "invariants": [],
    "lineage": [],
    "definitions": [
      {
        "from": null,
        "to": null,
        "text": "The limit on a night worker's normal hours of work: an average of eight hours for each 24 hours, measured over the applicable reference period (regulation 6(1) of the Working Time Regulations 1998). It is a limit on an AVERAGE, not a maximum for any single night, and regulation 6(3) fixes the reference period at 17 weeks unless a relevant agreement provides otherwise.",
        "instrument": "Working Time Regulations 1998 reg 6(1)"
      }
    ],
    "applicability": {
      "basis": "event_date",
      "note": "Measured over the reference period applicable to the worker, not over a tax year or a pay period: regulation 6(3) gives successive 17-week periods, or any period a relevant agreement specifies. The Regulations came into force on 1 October 1998 (reg 1(1)), which is the date this record carries.",
      "article": "Working Time Regulations 1998 regs 1(1), 6(1), 6(3); reg 2(1) for \"night worker\" and \"night time\""
    },
    "scope_note": "An average of eight hours per 24, for a NIGHT worker as regulation 2(1) defines one — not a limit on any individual shift, and not the 48-hour weekly limit in regulation 4(1), which is a separate figure. Unlike the 48-hour limit there is no individual opt-out: regulation 6 may be modified or excluded only by a collective or workforce agreement (reg 23) or by the Part 3 exceptions. A young worker's night work is prohibited outright by regulation 6A rather than limited, so this figure does not apply to one.",
    "notes": "An SI carry (ADR-0014), and a HOST-STATES one: no textual amendment touches regulation 6(1), so the 1998 Regulations state the value by their own words and their as-made text is its own frozen witness. Both documents are hashed into this record and the verdict recomputed at Gate 2. Contrast regulation 4(1) in the same instrument, whose 48 hours the probe CANNOT carry: SI 1999/3372 substituted the opening words of that paragraph, so the host-states claim fails and the amender's as-made text does not contain the value either. No archived GOV.UK page states this limit, so the record is single_source_A by design.",
    "record_version": 3
  },
  "receipt": {
    "record_hash": "sha256:d1e969e61f2b73f88dd4ca52be9d304949f4cced7f6191036bf96b8c99a071ed",
    "record_hash_of": "the `figure` object, serialized as UTF-8 JSON with 2-space indent, ensure_ascii=false and a trailing newline",
    "release_version": "3.0.0",
    "manifest": "https://statbook.co.uk/v1/releases/3.0.0/manifest.json",
    "record_url": "https://statbook.co.uk/v1/figures/employment.working_time.night_work_limit_hours.json",
    "sources": [
      {
        "role": "legislation",
        "citation": "https://www.legislation.gov.uk/uksi/1998/1833/made (SI 1998/1833 reg 6(1) as made: \"A night worker's normal hours of work in any reference period which is applicable in his case shall not exceed an average of eight hours for each 24 hours\"; in force 1 October 1998, reg 1(1))",
        "uri": "https://www.legislation.gov.uk/uksi/1998/1833/made",
        "retrieved": "2026-09-11T00:12:39Z",
        "content_hash": "sha256:702d61bf3f06765266766b01fd082464b0d0750526f6a1d8019d63ab3a2c9c26",
        "content_hash_of": "https://www.legislation.gov.uk/uksi/1998/1833/made/data.xml"
      }
    ],
    "verified": {
      "legislation": "2026-09-21T10:07:35Z"
    },
    "last_verified": "2026-09-21T10:07:35Z"
  }
}