You should note the following numbers in case of emergency:

Emergency services – 999 (Or 112 for non-emergency contact)
Flooding Incident Line – 0300 2000 100
Northern Ireland Electricity Networks – 03457 643 643
NI Gas Emergency Service – 0800 002 001
Northern Ireland Water Waterline – 03457 440 088
Housing Executive – 03448 920 901

There is also information about emergencies at this link:
https://www.nidirect.gov.uk/campaigns/be-ready-emergencies