From: Characterization of fatal injuries in oil and gas industry-related helicopter accidents in the Gulf of Mexico, 2004–2014
AIS severity
AIS severity score
Frequency
Proportion
Critical or maximal
AIS 5–6
25
71.4%
Severe
AIS 4
5
14.3%
Serious
AIS 3
3
8.6%
Moderate or minor
AIS 1–2
2
5.7%