Which factor is NOT considered an enabling condition?

The correct choice is based on the understanding of enabling conditions in the context of Layer of Protection Analysis (LOPA). Enabling conditions are factors that facilitate the occurrence of an incident or increase its likelihood. They are typically conditions that make it easier for a hazardous event to happen, rather than affecting the overall risk directly through active control measures or barriers.

Focusing on the probability of equipment maintenance, this factor relates to the reliability and upkeep of safety equipment and systems meant to prevent incidents. While critical for overall safety management, it does not inherently enable incidents to occur; instead, effective maintenance would typically reduce the likelihood of incidents by ensuring that safety systems function as intended. Thus, it does not fit the definition of an enabling condition.

In contrast, time-at-risk refers to the duration a system or process is exposed to potential hazards, making it an enabling condition since longer exposure amplifies risk. Campaign enabling conditions highlight specific scenarios that may increase the risk during operational phases. Lastly, the probability of incident escalation relates to how likely an incident is to worsen once initiated, which could also be viewed as an enabling factor depending on the context. This understanding clarifies why the probability of equipment maintenance stands apart as not being an enabling condition.