As indicated in 188.8.131.52 , connecting and disconnecting items within a product can pose safety risks or result in induced failures. As implied by the name, an induced failure is one caused by human error or misuse. Unsafe conditions also can result from human error and misuse. Mislabeling or lack of labeling, poorly written instructions, omission of warnings, inappropriate choices of displays and controls, and so forth can also lead to damaged or failed equipment, and to injury or death of operators or maintainers.
Some of the reasons that induced failures or unsafe conditions occur are:
- Operating or maintenance instructions or procedures are unclear or can be misinterpreted
- Warning labels are not properly placed or warnings in procedures not in correct sequence
- Items not functionally interchangeable are physically interchangeable
- Blind matings do not have self-guiding features
- High failure items require low-failure items to be removed to facilitate maintenance (unnecessarily increasing the removal rate for the latter)
- The operation of controls is contrary to intuition or common practice (i.e., a knob is turned counter-clockwise to increase power)
- Informational displays are difficult to read or interpret
- Tasks are physically awkward to perform
Appendix C has many design guidelines intended to avoid unsafe situations and to reduce the possibility of induced failures.