trapEventClassNumber is a user-configurable numeric code representing the alarm class associated with the event that triggered a trap. Admins define these class numbers to group related events, for example putting all temperature-related alarms into one class, so downstream systems can filter or prioritize traps by class rather than by individual event type. For example, an admin might assign class number 2 to all humidity-related events so a monitoring system routes every humidity trap identically regardless of whether it is High, Very High, or Return to Normal.