Table 4.

Description of changes in the contributing (human versus technical) factors from reporting to investigation level.

IR No.	Before investigation	After investigation
IR1	HF	TF
IR3	HF	TF
IR4	HF	TF
IR5	TF	HF
IR6	TF	HF
IR10	TF	HF
IR11	HF	HF & TF
IR14	TF	HF
IR15	TF	HF
IR16	HF	TF
IR17	TF	-
IR23	TF	HF
IR24	HF	TF
IR26	TF	-
IR28		HF
IR31	TF	HF
IR32	HF	-
IR34	HF	TF
IR36	TF	-
IR37	TF	HF

IR: incident report; HF: human factor; TF: technical factor.