When the firebox of a furnace or boiler has an explosive mixture by accumulation of large amounts of flammable gases, this will explode when igniting the burners.
- Upon start and restart.
- Cold start.
- After a furnace trip.
Challenges in the Field
- Reliability of instruments.
- No good procedure / practices.
- Fast restart required to avoid shut down.
Options to Get it Right
- Furnaces/boilers need to be purged well with air to remove all gasses and to avoid an explosive atmosphere, before igniting the burners.
- Procedures for start of furnaces and boilers must be available and up-to-date.
- Report problems with fully automated systems (burner management systems) or deviation from start-up procedure immediately.
- Limit the number of attempts to ignite a furnace/boiler (and keep sufficient time between attempts).
- Perform a leak test on the gas supply before igniting a furnace/boiler.
- Check atmosphere in the fire box before igniting the burners with a LEL meter
- Bypassing of safety instrumentation (flame eyes, gas detection, sensors) must be managed carefully.
- Limit the number of people in the vicinity when starting furnaces/boilers to those necessary for the start-up operation.
- Avoid time pressure when starting or restarting furnaces or boilers.
This page only summarises the guidance – refer to the EPSC website for further information.
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