http://www.legislation.gov.uk/nisr/2012/381/section/33/madeTHE ELECTRICITY SAFETY, QUALITY AND CONTINUITY REGULATIONS (NORTHERN IRELAND) 2012Dangerous animalsElectrical installation and servicingenGovernment Printer for Northern Ireland2014-10-07ELECTRICITY These Regulations replace the Electricity Supply Regulations (Northern Ireland) 1991 (S.R. 1991 No. 536) and the subsequent amendment (S.R. 1993/21). PART 8 33 1 A distributor shall give to the Department notification in accordance with paragraph (2) of those interruptions of supply involving their network where there has been— a any single interruption of supply, to any demand of 20 megawatts or more at the time of the interruption, for a period of three minutes or longer; or b any single interruption of supply, to any demand of 5 megawatts or more at the time of the interruption, for a period of one hour or longer; or c any single interruption of supply to 5,000 or more consumer’s installations for a period of one hour or longer. 2 The notification shall— a be sent in writing by the quickest practicable means immediately after the distributor becomes aware of the interruption; and b subject to paragraph (3) contain the particulars specified in Schedule 4. 3 The notification given to the Department shall, where the distributor is unable to give the full particulars required by Schedule 4, contain such of the particulars as are available to the distributor at the time of giving the notification, and any remaining particulars shall be sent in a supplementary notification in writing to the Department by the quickest practicable means immediately after they have become known.