Industrial Furnace Manufacture and Operation Safety Methodology in ‘Standard 86’ Warrants a Refresher Look

Safe practices for all industrial furnace applications can, undoubtedly, save lives. Accordingly, the National Fire Protection Association (NFPA) some time ago put required safeguards in place for most national combustion standards, most notably “NFPA Standard 86: Standard for Ovens and Furnaces.”

Given the importance of any protections established to help ensure a safe atmosphere when dealing with industrial furnaces, it is always a good time to review a 2002 article in The International Journal of Thermal Technology analyzing Standard 86 – which is as relevant today as it was over a decade ago.

Standard 86 applies to new installations of industrial furnaces and upgrades and maintenance and servicing of existing processing equipment, all of which are the focus of Industrial Furnace Service Hub’s professional services. Therefore, we fully support and adhere to Standard 86, which at its core outlines the safe operation of various types of industrial furnaces.

As the article also points out, key topics established in Standard 86 for an industrial furnace include the burner management system controller, the purge cycle, flame monitoring, positive fuel shut-off, training of operating and maintenance personnel and the periodic testing of safeguard devices.

Industrial Furnace Service Hub identifies constantly with the very crucial subjectsThe International Journal of Thermal Technology essay explores – subjects that should be re-examined and re-studied in any industrial furnace situation:

  • “Standard 86 requires that a burner management system (BMS) controller ‘Shall be listed for use in the service intended,’ the status of which can be checked by an insurance underwriter for the equipment covered. ... It further includes the minimum requirements a BMS controller must meet. ... Also, Standard 86 specifies that a trip of the burner system by any safety device requires manual intervention of a trained operator to correct a fault situation prior to restarting the burner for normal operation.”

  • “The purge airflow and time must be sufficient enough to allow ‘at least four standard cubic feet of fresh air or inert gas per cubic foot of heating chamber’ ... . Standard 86 requires that ‘Prior to each furnace heating system start-up, provision shall be made for the removal of all flammable vapors and gases that might have entered the chambers during the shutdown period.’”

  • “Standard 86 requires that each pilot and main flame have independent flame monitoring, but does allow for one flame sensor for both if the pilot is an interrupted pilot or if it is a self-piloted burner. The flame monitoring device should have a maximum flame failure response time of 4 seconds or less and should be interlocked into the burner’s safeguard control logic. The loss of a flame signal should cause a master fuel trip, which closes the main fuel safety shut-off valves, thereby stopping burner operation.”

  • “Standard 86 requires that all operating, maintenance and appropriate supervisory personnel be thoroughly instructed and trained to ensure knowledge of and practice of safe operating procedures. The standard also requires regular retraining along with recommended initial training to maintain the thorough understanding. Training for gas-fired furnaces should include combustion principles, explosion hazards, ignition sources, confined space entry and functioning of safety and control devices. Operating instructions including piping and wiring diagrams, start-up and shut-down procedures and maintenance instructions also should be included for the furnace.”