Human Error

Old view

human error happened

New view

system error happened

Hierarchy of controls (defend against errors)

elimination, substitution, engineering controls, admin controls, PPE

(Most effective to least effective)

elimination

remove physical hazard

substitution

replace hazard

engineering controls

isolate people from the hazard

admin controls

change how people work

PPE

personal protective equipment to protect workers

prevention examples

alarms, barriers

fail-safe

a safeguard, error occurs, but results aren’t catastrophic

Swiss cheese model

shows that accidents happen because of multiple failures in a system

hole= failure in system

cheese slice= layer of defense

Skill-based error

mistake happens during an automatic task

rule-based error

use the wrong procedure when doing a task that you know how to do

knowledge-based error

don’t know how to do a task

resilience (error management)

respond to unexpected + recover from mistakes

blaming humans can impact

reporting + fixing system errors

taxonomy

identifies the type of error made (rule, knowledge, skill-based)

ways for people to catch/recover from error

undo button, error messages

closed loop

system uses feedback to adjust error potential

open loop

system doesn’t use feedback to adjust error potential

choking happens when you

try too hard