Table 2.
The error producing conditions
| Error producing conditions | Weight | |
|---|---|---|
| A1 | Unfamiliarity with a situation which is potentially important but only occurs infrequently or is novel | 17 |
| A2 | A shortage of time available for error detection & correction | 11 |
| A3 | A low signal-to-noise ratio | 10 |
| A4 | A means of suppressing or overriding information or features which is too easily accessible | 9 |
| A5 | No means of conveying spatial & functional information to operators in a form which they can readily assimilate | 8 |
| A6 | A mismatch between an operator’s model of the work & that imagined by a Designer | 8 |
| A7 | No obvious means of reversing an unintended action | 8 |
| A8 | A channel capacity overload, particularly one caused by simultaneous presentation of non-redundant information | 6 |
| A9 | A need to unlearn a technique & apply one which requires the application of an opposing philosophy | 6 |
| A10 | The need to transfer specific knowledge from task to task without loss | 5.5 |
| A11 | Ambiguity in the required performance standards | 5 |
| A12 | A mismatch between perceived & real risk | 4 |
| A13 | Poor, ambiguous, or ill-matched system feedback | 4 |
| A14 | No clear, direct, & timely confirmation of an intended action from the portion of the system over which control is to be exerted | 4 |
| A15 | Operator inexperience (e.g., A newly-qualified tradesman, but not an “expert”) | 3 |
| A16 | An impoverished quality of information conveyed by procedures & person interaction. | 3 |
| A17 | Little or no independent checking or testing of output. | 3 |
| A18 | A conflict between immediate and long-term objectives | 2.5 |
| A19 | No diversity of information input for veracity checks | 2.5 |
| A20 | A mismatch between the educational achievement level of an individual and the requirements of the task | 2 |
| A21 | An incentive to use other more dangerous procedures | 2 |
| A22 | Little opportunity to exercise the mind and body outside the immediate confines of a job | 1.8 |
| A23 | Unreliable instrumentation (enough that it is noticed) | 1.6 |
| A24 | A need for absolute judgements which are beyond the capabilities or experience of an operator | 1.6 |
| A25 | Unclear allocation of function and responsibility | 1.6 |
| A26 | No obvious way to keep track of progress during an activity | 1.4 |
| A27 | A danger that finite physical capabilities will be exceeded | 1.4 |
| A28 | Little or no intrinsic meaning in a task | 1.4 |
| A29 | High-level emotional stress | 1.3 |
| A30 | Evidence of ill-health amongst operatives, especially fever | 1.2 |
| A31 | Low workforce morale | 1.2 |
| A32 | Inconsistency of meaning of displays and procedures | 1.2 |
| A33 | A poor or hostile environment (below 75% of health or life-threatening severity) | 1.15 |
| A34 | Prolonged inactivity or highly repetitious cycling of low mental workload tasks | 1.1 |
| A35 | Disruption of normal work-sleep cycles | 1.1 |
| A36 | Task pacing caused by the intervention of others | 1.06 |
| A37 | Additional team members over and above those necessary to perform task normally and satisfactorily | 1.03 |
| A38 | Age of personnel performing perceptual tasks | 1.02 |