When you hear about large-scale combustion explosions and loss of human life, you wonder how this tragedy could happen. And, yet, the No. 1 cause of industrial fuel and combustion system explosions is human error. Therefore, the most critical element of every combustion safety system is not pressure gauges or shut-off valves, but rather knowledgeable, well-trained operators. Training is so critical that the National Fire Protection Association (NFPA) requires that “all operating, maintenance, and supervisory personnel shall receive regularly scheduled retraining and testing.” 

In all, the NFPA publishes three prescriptive sets of standards to help keep your staff and combustion equipment safe, and each of these standards stress the value of operator training. 

  • NFPA 54 — National Fuel Gas Code
  • NFPA 85 —Boiler and Combustion Systems Hazards (> 12.5 MMBtu/hr)
  • NFPA 86 —Standard for Ovens and Furnaces

NFPA standards apply to new installations and modifications of existing equipment, and some insurance underwriters apply the current standards retroactively. Operations that use heat are nearly limitless, but larger, common combustion applications include pulp and paper processing, tempered glass production, tire manufacturing, paint/drywall/shingle manufacturing, power plants, coating operations, ethanol and asphalt production, wastewater and sewage treatment, plastic bottle manufacturing, college campuses and breweries to list just a few. Understanding and enforcing applicable NFPA standards is paramount to the safety of every business using a combustion or heat treatment system.

Each NFPA standard has hundreds of pages covering the necessities for safe design, installation, operations, and maintenance of the respective equipment. This article gives a cursory overview of NFPA 54, 85 and 86, and provides guidelines to obtain safety training. When it comes to fuel-fired equipment operation, training is literally a life and death issue. 

Consider this: The National Board of Pressure Vessel Inspectors and the NFPA have identified that 83% of boiler/pressure vessel accidents, 69% of injuries and 60% of recorded deaths were a direct result of human oversight or lack of knowledge. Poor training also leads to production outages that cost millions of dollars in business interruption, supply chain delays, lost orders and competitiveness. Many companies only learn the value of combustion system training after an accident or expensive shutdown has occurred. 

NFPA 54 — National Fuel Gas Code

Also known as ANSI Z223.1, the NFPA 54 standard details minimum safety requirements for the installation of gas piping systems, appliances and equipment supplied with LP-gas, natural gas or manufactured gas. Basically, NFPA 54 addresses the how’s and why’s of:

  • Piping system design, materials, and components
  • Piping sizing
  • Installing pipes, outlets, and inside concealed spaces 
  • Inspection, testing and purging procedures
  • Installation and venting of appliances.

NFPA 54 is specific; it does not apply to natural gas systems operating at pressures above 125 psi, propane systems operating over 50 psi, gas/air mixes within the flammable range at pressures over 10 psi, and several other types of systems.

NFPA 85 — Boiler and Combustion Systems Hazards

NFPA 85 gives those involved with large boiler installations and combustion systems the information they need for fire safety compliance, from system design and installation to inspection. Specifically, the standard addresses single burner boilers, multiple burner boilers, stokers, and atmospheric fluidized bed boilers with a fuel input rating of 12.5 million Btu/hr or greater. It also covers pulverized fuel systems at any heat input rate, fired or unfired steam generators, and other combustion turbine exhaust systems.

NFPA 85 offers guidelines as to the strength of a structure, operation and maintenance procedures, combustion and draft control equipment, safety interlocks, alarms, trips, and other related controls that are essential to safe equipment operation.

NFPA 86 — Industrial Ovens and Furnaces

NFPA 86 outlines the safe operation of Class A, Class B, Class C and Class D ovens, dryers, and furnaces, thermal oxidizers, and any other heated enclosure used for processing materials. NFPA 86 guidelines set standards as to how industrial furnaces and ovens are to be designed and operated in order to promote safety, with each Class of operation organized into four main categories: location and construction, heating systems, operational requirements, and safety equipment.  Beyond these basic categories each Class may have unique conditions addressed for distinct hazards such solvents or special atmospheres.

NFPA 86 specifically states that personnel who operate, maintain or supervise the oven or furnace shall be thoroughly instructed and trained in their job functions, demonstrate an understanding of safe operation procedures, be kept current with changes in the equipment and operating procedures, and shall receive regular refresher training. 


Training your staff to understand and comply with NFPA 54, 85 and 86 standards will minimize the risk of a catastrophic event. In addition, training enhances overall productivity and helps cut costs. For example, having in-house staff with the skills to recognize defects will lead to better fuel efficiency, fewer interruptions, and the avoidance of outages and downtime. And of course, training is a compliance requirement to be completed on an annual basis. 

There are four common ways for your staff to obtain training, all of which can meet requirements to varying degrees.

One, attend a combustion workshop. Doing so will offer a more in-depth experience for your staff since workshops typically include hands-on training and face-to-face instruction. Also, you’ll be able to network with combustion safety and design engineers during breaks and lunches. Workshops normally award attendees with the documentation needed to supply proof of completion. They are held on-site at a training facility, or the instructor may go to the customer’s site to train staff on the plant’s fuel-fired systems and what ancillary equipment is required to support its operation.

Two, in this age of COVID-19, online or remote training programs are a smart choice. Pre-recorded webinars are available 24/7, so attendees can learn at their own pace and convenience. Remote live workshops can be broadcast on Zoom, Cisco, Webex or other digital platforms. This lets attendees interact with the instructor and participate in simulations, so they’ll be equipped with the knowledge & skills required to operate combustion systems without leaving their office.

Three, there is OEM instruction. NFPA 86 requires manufacturers to provide instruction upon installation of new ovens, dryers, thermal oxidizers, furnaces and boilers. However, OEMs are not required to return to installation sites to educate operators on the newest changes in national and international regulations, or in equipment design. While the OEM’s initial training may suffice to get the new equipment up-and-running, it is not enough to guarantee ongoing safety.  If process changes have been made after installation, the original OEM training may be out of date.

Fourth, you can develop your own program. This endeavor entails an investment in time, research, continuous improvement, and the participation of dedicated team leaders. If you take this path, you’ll likely need to hire outside experts to ensure that the training curriculum encompasses all NFPA requirements including general safety, operation of equipment, and the latest code protocols.

Case history

On June 18, 2007, one of two boilers at a manufacturing plant in Tennessee exploded causing extensive damage to the facility and surrounding area, and seriously injuring one employee.  The 2000-built high-pressure firetube boiler was operating concurrently with a second high-pressure boiler to handle the steam demand of plant operations. 

Tennessee state officials concluded that there were a number of factors that contributed to the accident: lack of standard training and boiler operation procedures, inadequate boiler attendance and record keeping, inadequate and improper boiler maintenance, and inoperative and improper operating controls and safety devices. As part of its recommendations, officials stated, the plant “should develop procedures for the training and certification of all boiler operators.”

Conclusion: Training is essential

Human error is the largest cause of industrial fuel and combustion system accidents, explosions, fires and outages. Fuel-fired equipment incidents can be extremely dangerous and necessitate special attention, engineering know-how, experience and especially, training. Understanding and complying with national codes, along with establishing a safety culture, will save lives and improve the competitiveness of any company using fuel-fired equipment.