LAYERS OF PROTECTION ANALYSIS FOR HUMAN FACTORS (LOPA-HF) Paul Baybutt, Primatech Inc. ASSE Symposium on Human Error In Occupational Safety, March 13 (cid:150) 14, 2003, Atlanta, Georgia 1 PREMISE Plethora of human error classification schemes ! and human factors models Importance of human error contributions to ! accidents in process plants is well recognized Large body of knowledge on human ! errors/factors Few companies have applied it to their existing ! plants or designs for new ones 2 WHY NOT? CONTRIBUTING REASONS Language of human factors not understood ! Potential benefits not recognized ! Cost of studies ! Acceptance of a culture of blame ! i.e. fix people, not the process Discomfort with a field that sounds (cid:147)touchy- ! feely(cid:148) (cid:147)Most human beings have an almost infinite capacity for taking things for granted.(cid:148) Aldous Huxley 4 CONTRIBUTING REASONS (CONTD.) Absence of ! human factors framework to which plants can relate simple and straightforward methods how to fix human factors problems 5 CONTRIBUTING REASONS (CONTD.) Field seems so broad it appears overwhelming ! Existing safety programs viewed as adequate ! Perceived to benefit only safety ! not productivity, operability, quality, etc. Value not convincingly demonstrated ! (cid:147)Minds are like parachutes; they work best when open.(cid:148) Lord Thomas Dewar 6 CONTRIBUTING REASONS (CONTD.) Plants do not have the time or resources ! overwhelmed with other programs thinly staffed operating in a highly competitive environment No imperatives, or motivating factors ! contributions to financial performance regulations 7 PATH FORWARD Many companies covered by PSM/RMP ! Process hazard analysis (PHA) required ! (cid:147)The PHA shall address human factors(cid:148) ! Present approaches only pay lip service ! Find a better way to mount HF on this horse ! LOPA-HF (cid:147)To err is human; to forgive, infrequent.(cid:148) Franklin P. Adams 8 OVERVIEW Causes of process accidents ! Human factors in PHA ! Human factors models ! LOPA-HF ! Example ! 9 PROCESS ACCIDENTS Equipment Human External Failures Failures Events