Honeywell BW MaxXT II User Manual page 52

5% (of reading) Over-span
When enabled, the detector automatically over-spans the LEL sensor by 5% of the span
concentration to ensure the span meets CSA standards. After enabling this option in Safety
Suite Device Configurator (SSDC), a calibration (manual or using the IntelliDoX) must be
completed to fully enable this option.
BW MaxXT II 51 User Manual