failures Flashcards
4 categories of failure causes
aims
organsiations
methods
people
aims causes
ill defined goal
not enough detail on requirements
unrealistic
organisaztion causes
not enough resources size methodology planning and control organiszation
methods causes
technical issue
technological failure
people
people managment
personality failure
wrong people
user needs
who made the swiss cheese model
James REason
what did james susggest for the swiss chees modeel
put up more barriers with fewer holes
two types of failures
latent- prior , lying fdormant
active, occured at time of failure
3 levels of human error
1 skill based error
2 rule based error- routine decision making “if…then..”
3 knowlegde based error-using basic principals to determin way forward
skill based error (action slips) ususaly due to ..and some examples
due to inattention /overattention
data-driven error interruptions omission-missing out step repititions- repeating completed step reversals undoing completed step
rule based error
wrong strong rule
new info , dont change rule
too much info, overlooked critical
knowledge based error
selectivity of data
confirmation bias
over confidence
causality
error detection needs
feedback mechanism (monitoring) discrepancy between expected/observed
error prevention methjods
training right environment well design tools checklists simulations constraints
allow for human errors
back up system limitors factor of safety automate tasks extra protection
all to common
lives depend on tech, shows to be bad under low load, then fails
failure lessons 1-8
1 cannot design out failure 2 dont economise on safety 3 cutting edge +prestige bad 4 testing andf checking 5 number 8 wire bnad 6 avoid group thinking 7 tunel vision 8 culture to bring up issues
rickovers seven principals of safe systems
1 commitment to quality 2 capable people 3 supervisors need to listen 4 everyone needs respect for risks 5 training 6 functions given to spcific people, repair etc 7 learn from mistakes
