Risk assessment techniques for civil aviation security Galileo Tamasi a , Micaela Demichela b,n a Ente Nazionale per l’Aviazione Civile—Direzione Progetti, Studi e Ricerche, Via di Villa Ricotti, 42, 00161 Roma, Italy b SAfeR—Centro Studi su Sicurezza, Affidabilit  a e Rischi, Dipartimento di Scienza dei Materiali e Ingegneria Chimica, Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Torino, Italy article info Article history: Received 25 May 2009 Received in revised form 2 March 2011 Accepted 3 March 2011 Available online 8 April 2011 Keywords: Civil aviation security Airport security Risk assessment RAMS Terrorist threats abstract Following the 9/11 terrorists attacks in New York a strong economical effort was made to improve and adapt aviation security, both in infrastructures as in airplanes. National and international guidelines were promptly developed with the objective of creating a security management system able to supervise the identification of risks and the definition and optimization of control measures. Risk assessment techniques are thus crucial in the above process, since an incorrect risk identification and quantification can strongly affect both the security level as the investments needed to reach it. The paper proposes a set of methodologies to qualitatively and quantitatively assess the risk in the security of civil aviation and the risk assessment process based on the threats, criticality and vulnerabilities concepts, highlighting their correlation in determining the level of risk. RAMS techniques are applied to the airport security system in order to analyze the protection equipment for critical facilities located in air-side, allowing also the estimation of the importance of the security improving measures vs. their effectiveness. & 2011 Elsevier Ltd. All rights reserved. 1. Introduction The terrorist attack of September 11th 2001, observed from a socio-economic, cultural and political point of view, had a tremendous negative impact on air transport never seen before in aviation, unparalleled in history [1–3]. Proper measures have soon been taken following the considera- tions emerged after the attacks and most of they are listed in the seventh edition of Annex 17 of the Chicago Convention of the International Civil Aviation Organization (ICAO) [4,5]. Annex 17 is the key document concerning aviation security and is the primary Annex for security-related Standards and Recommended Practices. ICAO realised immediately the urgency and the need for restoring the integrity of the aviation system and met representatives from 32 nations to discuss new security measures. The ICAO has then implemented 66 security standards and 16 Recommended Practices (SRPs) and has recommended the Universal Security Audit Program (USAP). USAP program promotes global aviation security through the auditing of Contracting States on a regular basis to determine the status of implementation of ICAO Annex 17 security standards. Since 9/11, new measures have been taken in order to protect the aircrafts from hijacking and sabotage threats and new preventive methodologies have been developed to prevent actions, which could threaten the aircraft security. Other methods and innovative procedures are being developed to improve the airport security system and to protect it from new threats, such as the Laser Beams which could blind the pilots, the use of Hand Portable Air Defense Systems (MANPADS) and explosives which could shoot down the aircraft during the landing or take-off procedures. The heads of the aviation industry, such as ACI, IATA, IACA, Airbus and Boeing have formed the Global Aviation Security Audit Group (GASAG). They strongly affirm that the security of the aviation (AVSEC) is not only a responsibility of the civil aviation industry, but also is a security problem of the nations. They have also underlined the importance of government bodies and of the intelligence in the control of the new emerging threats. New countermeasures was suggested, included hundred per cent baggage screening, explosives detection, biometric identifi- cation of passengers and, maybe, remote check-in, risk based threat perception analysis and identification of non-risk passen- gers instead of the rarer risk-passenger, as well as in-flight measures like using Sky Marshals, strengthening cockpit doors and cabin monitoring from within the cockpit [6–11]. Thus far, carrying arms has been banned, but the possibility of arming, or, at least, training the crew in unarmed combat is being Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/ress Reliability Engineering and System Safety 0951-8320/$ - see front matter & 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.ress.2011.03.009 n Corresponding author. Tel.: þ390110904629; fax: þ390110904665. E-mail addresses: g.tamasi@enac.rupa.it (G. Tamasi), micaela.demichela@polito.it (M. Demichela). Reliability Engineering and System Safety 96 (2011) 892–899