{
 "id": "hp_noise_limit_england",
 "name": "Heat pump noise limit for permitted development, England",
 "category": "heat_pump_noise",
 "value_num": 37.0,
 "display": "37 dB(A)",
 "unit": "sound pressure level from the heat pump, LAeq over 5 minutes, at every assessment position",
 "period_start": "2025-05-29",
 "period_end": null,
 "period_kind": "data",
 "deadline": null,
 "source_url": "https://mcscertified.com/wp-content/uploads/2025/04/MCS-020-a-Issue-1.1-Final.pdf",
 "source_org": "MCS, MCS 020 a) Issue 1.1",
 "checked_at": "2026-09-30",
 "recheck_by": "2026-12-29",
 "history": [],
 "public_note": "In England an air source heat pump is permitted development only if the MCS 020 a) sum puts it at or below 37.0 dB(A) at every assessment position. An assessment position is a point 1 metre outside the middle of a door or window to a habitable room of a neighbouring property. The sum is rounded to one decimal place before it is compared.",
 "next": null,
 "url": "https://hearthsum.co.uk/api/hp_noise_limit_england.json"
}