I went to my first fire scene within the first month of being employed as an attorney. My boss handed me a copy of NFPA 921 and told me to read it.

NFPA 921 is the National Fire Protection Association’s Guide for Fire and Explosion Investigations, and it can be the difference between winning and losing a case. If you anticipate handling fire cases in your career, you must be familiar with NFPA 921. If you will be handling many fire cases, you should know it well enough that you can easily find the section you’re looking for when under pressure.

NFPA 921 isn’t just a guide for fire professionals. It’s a roadmap for an attorney from the initial investigation of a fire through discovery and trial.

From the beginning of my career, I have been involved with the investigation of fire losses. While I do not think my boss who told me to read NFPA 921 my first week as an attorney meant I should read it cover to cover, that’s exactly what I did. At first, the guide was more confusing than useful. Reading it, I was a bit lost. There are a lot of technical terms, and I had zero background in fire investigation.

But, even though I did not understand much on that first read of NFPA 921, that book set a foundation for my career. It was interesting—a niche area I thought could be fun to explore. And today, eight years into my career, I understand the majority of what is in the guide.

Courts have repeatedly held that NFPA 921 is an acceptable peer-reviewed authoritative work and generally accepted in fire-investigation communication. One court called it “the Bible for forensic fire-scene investigation.”

The most recent iteration of NFPA 921 was published in 2017 and has 30 chapters. The original version, published in 1992, had fewer than 20 chapters. The next edition of NFPA 921 is in the works and is scheduled to be released in 2021.

Which sections of NFPA 921 are especially important for an attorney to read and understand to best assist clients in the pursuit or defense of fire claims?

Most attorneys should start with Chapter 17 when handling a so-called young fire claim.

In an ideal world, a client will call you immediately after a fire occurs and you can demand preservation of the fire scene and evidence pending an official investigation. Chapter 17 addresses preservation of the fire scene and physical evidence as well as considerations in documenting the scene and collecting physical evidence.

As I am usually on the defense side of the aisle, I always send correspondence to the claimant’s attorney or representative referring to Chapter 17 and demanding preservation of the scene and physical evidence until the parties can retain their own experts and conduct an origin and cause investigation of the scene.

Origin-and-cause fire investigators will tell you that it is much easier to offer an opinion when they’ve been to a fire scene. Likewise, it’s much easier for attorneys to defend or pursue a fire case when they themselves have been to the scene or at least had it properly documented by an expert.

Chapters 18 and 19 deal with determining the origin and cause of a fire. Both chapters have very helpful diagrams that illustrate the scientific method in determining both the origin and cause.

You would be surprised at how many experts have been tripped up when confronted with these charts. When NFPA 921 was first published, there was a lot of pushback from members in the fire investigation community. Prior to NFPA 921, the fire investigation community was known to have many “fire-whisperers.” These were so-called experts who had no real scientific training and opined to origin and cause based upon subjective and speculative means. Now experts must be able to explain how they arrived at their conclusions based purely on science. No longer is “because I said so,” a valid opinion in a fire case. So it is imperative that, in a deposition or at trial, an attorney go over how the expert arrived at his or her opinion.

In preparing experts for deposition or trial, be sure they can adequately explain their opinions and how they arrived at them scientifically. This helps experts demonstrate that their methodology and reasoning is scientifically valid and can be applied to the facts of the case, thus reducing the chances that their opinions will be excluded at trial.

Many times, a fire case comes down to a “battle of the experts.” Whichever expert has a better explanation of just how he or she determined the origin or cause of a fire is likely going to win.

In addition to chapters 17, 18, and 19, there are also helpful chapters near the beginning of NFPA 921. These provide definitions of many fire-related terms and phrases.

There are also chapters that provide the basis for methodology and fire science. And some chapters are tailored for a specific type of fire. I recently watched a senior attorney, who had years of experience in fire investigation and a scientific background, try a case. When opposing experts introduced an entirely new theory at trial, this attorney was able to recall sections of NFPA 921 that refuted it. He continued to use NFPA throughout his cross-examination of the experts and revisited it extensively during the closing statement. He did not solely rely on his experts to know the science of the case; he knew it himself and could convey the ideas in layman terms to the jury.

The case involved an appliance fire, which happens to be the subject of an entire chapter of NFPA 921: Chapter 26, in the current edition.

NFPA 921 has revolutionized fire investigation. The importance of the publication for an attorney defending or pursuing a fire case becomes more and more apparent each year. There are hundreds of state and federal cases that cite NFPA 921 in opinions, and that number will only grow. Courts call it the “gold standard” in the field of fire science.

Fire and explosion investigation is an ever-evolving science, and it is not an area you can learn about once and rest on your laurels. If you are intimately familiar and comfortable with NPFA 921 and keep abreast of recent developments in the area, you give yourself an immeasurable advantage in any fire case.

This article originally appeared in Goldberg Segalla’s Product Liability Playbook. Read the issue here.