The rule
One negative answer stops the permit. Answers are three way: yes, no, not applicable. Once the non-conformity is corrected the same question is asked again; work does not start on a note saying "to be fixed".
Why the third option is necessary
On a yes/no only list, questions irrelevant to the job squeeze the crew. People answer "yes" to an irrelevant question rather than break the rule, and the list begins to lie. "Not applicable" removes that pressure — at a price: every question marked not applicable must be recorded together with who marked it.
Paper versus system
| Question | On paper | What a system could do |
|---|---|---|
| Is the detector calibration valid? | A tick box | No permit opens until the device record is read |
| Does the equipment carry a valid tag? | A question | Non-conforming equipment cannot be selected |
| Is a rescue plan attached? | A reminder | The approval step does not open without the attachment |
| Is the person certified? | Writing a name | Someone with an expired certificate cannot join the party |
How the rule erodes
The single no rule is the easiest rule to erode, usually in three ways: saying yes to irrelevant questions, passing a non-conformity on a verbal promise, or opening the permit under a different category so the hard questions never appear. All three stay invisible because none of them is recorded.
The number that matters
The real indicator in a permit system is not how many permits are opened but how many are stopped, and on which codes. A system that never stops anything is a checklist without a gate.