The International Air Transport Association have this week celebrated the first 20 years of the IATA Operational Safety Audit (IOSA) . Here at Airline Ratings we place great emphasis on the IOSA audit and its impact on an airlines accident rate, awarding airlines extra safety stars when they have passed the audit.

Why? Because it lowers the accident rate dramatically

The safety data confirm that in aggregate, airlines on the IOSA registry have a lower accident rate than airlines that are not on the IOSA registry. Since 2005, the all-accident rate for airlines on the IOSA registry is 1.40 per million sectors, compared with 3.49 per million sectors for non-IOSA airlines. In 2022, IOSA registered carriers outperformed those not on the registry by a factor of four (0.70 accidents per million sectors vs. 2.82 accidents per million sectors).

Suggested Read: AirlineRatings safety ratings explained

Nick Careen, IATA’s Senior Vice President Operations, Safety and Security stated..

"Over the past two decades, IOSA has made a major contribution to improving safety, while reducing the number of redundant audits. While it is a condition of membership in IATA, more than 100 non-IATA member airlines also see the value of participating and we welcome others. Likewise, while more than 40 governments use or are intending to use IOSA in their safety oversight programs, many more do not."

Reflecting the strong safety performance of airlines on the IOSA registry, IATA entered into IOSA’s third decade with a call for regulators to recognize the significant contribution to safety that IOSA makes as the global standard for airline operational safety and to incorporate IOSA into their own safety regulatory oversight programs.

Currently, some 417 operators are on the IOSA registry, of which 107 are non-IATA members - Airlines not yet on the IOSA registry are encouraged to join.

A History of Continuous Improvement

• IOSA was launched in September 2003 with Qatar Airways as the first airline to be audited and join the IOSA Registry. IOSA has been a requirement for IATA membership since 2006.
• It is also a condition of membership in the three global airline alliances, as well as a number of regional airline associations.
• It is used by regulators in numerous countries to complement their safety regulatory oversight programs, and as the primary means to verify operational safety for many airline codeshare arrangements.
• The audit assesses an airline’s conformity with the IOSA standards and recommended practices . These are based on the internationally agreed standards and recommended practices set down and maintained through the International Civil Aviation Organization (ICAO).
• IOSA was developed in cooperation with aviation regulatory bodies, including Australia’s Civil Aviation Safety Authority (CASA), the European Union Aviation Safety Agency (EASA), US Federal Aviation Administration (FAA) and Transport Canada.
• Last year, IATA began evolving IOSA to a risk-based model under which audits are tailored to the operator’s profile and focusing on high-risk areas. The new approach also introduces a maturity assessment of the airline's safety-critical systems and programs.

Of course no one at IATA or AirlineRatings can predict an accident or guarantee anyone's safety on any airline at any time. We would however, always encourage choosing an IOSA audited airline.