Critical Infrastructure Sector
Each national or international strategy and policy identifies different categories of sectors that are considered to offer vital services and thus require protection. A 2008 survey examined the policies of 25 countries and identifies as the most frequently mentioned the following sectors:
- Banking and Finance,
- Central Government / Government Services,
- (Tele-)Communication / Information and Communication Technologies(ICT),
- Emergency / Rescue Services,
- Energy / Electricity,
- Health Services,
- Transportation / Logistics / Distribution, and
- Water (Supply).
Official European Definition
- Electricity: Infrastructures and facilities for generation and transmission of electricity in respect of supply electricity
- Oil: Oil production, refining, treatment, storage and transmission by pipelines
- Gas: (a) Gas production, refining, treatment, storage and transmission by pipelines, (b) LNG terminals
- Road transport
- Rail transport
- Air transport
- Inland waterways transport
- Ocean and short-sea shipping and ports
Other International Definitions
UNISDR presents the following examples of critical infrastructures: transport systems, air and sea ports, electricity, water and communications systems, hospitals and health clinics, and centres for fire, police and public administration services .
UK's national infrastructure is categorised into nine sectors:
# communications # emergency services # energy # financial services # food # government # health # transport # water
Presidential Policy Directive 21 (PPD-21): Critical Infrastructure Security and Resilience identifies 16 critical infrastructure sectors:
- Chemical Sector
- Commercial Facilities Sector
- Communications Sector
- Critical Manufacturing Sector
- Dams Sector 
- Defense Industrial Base Sector
- Emergency Services Sector
- Energy Sector
- Financial Services Sector
- Food and Agriculture Sector
- Government Facilities Sector
- Healthcare and Public Health Sector
- Information Technology Sector
- Nuclear Reactors, Materials, and Waste Sector
- Transportation Systems Sector
- Water and Wastewater Systems Sector
Each sector falls under the responsibility of a designated Sector-Specific Agency (SSA).
- Transport and traffic (aviation, maritime shipping, inland waterway transport, rail traffic, road traffic, logistics)
- Energy (electricity, mineral oil, gas)
- Information technology and telecommunication (telecommunication, information technology)
- Finance and insurance sector (banks/financial institutes, insurance companies, financial service providers, stock exchanges)
- State and administration (government and administration, parliament, judicial institutions, emergency and rescue services including disaster control)
- Food (food industry, food trade)
- Water (public water supply, public wastewater disposal)
- Health (medical care, pharmaceuticals and vaccines, laboratories)
- Media and culture (broadcasting (television and radio), printed and electronic press, cultural assets, highly symbolic buildings)
- E. Brunner, M. Suter, International CIIP Handbook 2008/2009: An Inventory of 25 National and 7 International Critical Information Infrastructure Protection Policies, A. Wenger, V. Mauer, M. Dunn (Eds.), CRN Handbooks, Vol. 4, no. 1, Center for Security Studies (CSS), Zurich, Switzerland, September 2008.
- Council Directive 2008/114/EC of 8 December 2008 on the identification and designation of European critical infrastructures and the assessment of the need to improve their protection.
- 2009 UNISDR Terminology on Disaster Risk Reduction, United Nations International Strategy for Disaster Reduction (UNISDR), Geneva, Switzerland, May 2009.
- National Infrastructure Protection Plan, Partnering to enhance protection and resiliency, US Department of Homeland Security, 2009
- Presidential Policy Directive -- Critical Infrastructure Security and Resilience, PPD-21, 2013
- Note: The Dams Sector comprises dam projects, navigation locks, levees, hurricane barriers, mine tailings impoundments, and other similar water retention and/or control facilities. Dams are vital to the nation's infrastructure and provide a wide range of economic, environmental, and social benefits, including hydroelectric power, river navigation, water supply, flood control, and recreation.
- Unpublished working glossary of UP KRITIS and BSI, 2014