‘This is a huge red flag:’ Fireworks expert raises concerns over deadly Esparto explosion

Just over a week ago, a massive explosion at a fireworks facility in the Yolo County town of Esparto killed seven people, injured two others and started the 80-acre Oakdale Fire.

Cal Fire is leading the investigation into the incident, which is in its early stages, but many questions remain unanswered about a potential cause of the explosion and the Bay Area company associated with the Esparto facility, Devastating Pyrotechnics.

In a statement Cal Fire says it is “actively tracking down numerous leads and have served multiple search warrants as part of the investigation process,” but declined to provide additional details.

A fireworks expert who sits on the agency’s General Fireworks Advisory Committee — which includes end users, fire officials, industry representatives and others — says the explosion raises several red flags.

Julie Heckman is the Executive Director of the American Pyrotechnics Association, a major trade association for commercial fireworks, and has 37 years of experience in the business.

Heckman says Devastating Pyrotechnics is not a member of her organization. She spoke with Insight host Vicki Gonzalez about her concerns, safe storage for fireworks and the lessons that could be learned from the deadly blast.

Cal Fire was invited to join Insight to discuss the investigation, but were unable to attend.

This interview has been edited for length and clarity.

Interview highlights

How did you learn about what happened in Esparto last week? 

One of my board members texted me as soon as it happened and I was able to tune in and watch the live coverage for about 45 minutes, which was just very unsettling to watch. 

I'm not certain that was just fireworks, to be quite frank with you. Looking at the structure of that warehouse, that is a very uncommon setup for professional display fireworks. Typically, everything has to align with the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) regulations. 

I did not see that just based on my observations of looking at the structure of the warehouse. But also in the performance of just how the explosion occurred, it looked far more energetic than even just professional display fireworks. So, I would be curious… since that facility was licensed for agriculture, was there something else there? 

A photo of the Oakdale Fire taken July 1, 2025.Courtesy of the Cal Fire Sonoma-Lake-Napa Unit

From your experience being in this industry for 30 years, how common is a deadly explosion like this?

It is very, very rare. Typically when there is an incident it's either involved in manufacturing, and we don't have very many firework manufacturers in the United States, or it's the preparation of display products, like prior to setup. So [in] the most significant accidents… the most common thread is the attachment of electric matches or igniters to a display shell. That is typically done outdoors. You would separate your product, you would work with a very small quantity. In the event something happens, you would not have a mass explosion. 

What are some of the best practices for storing pyrotechnics or fireworks? 

Separation is critical. That is spelled out in the ATF regulations based on the construction of the magazine or the warehouse—which really is not a term we use for display products. There might be a process building, packing building or storage — which is typically in a Type 1 or Type 4 magazine — but the regulations specify a table of distance based on the net explosive weight that magazine is authorized to hold. ATF establishes those limits for the individual magazines, and they come and do annual inspections. They will conduct inventory, they want to know that you did not exceed the maximum amount of net explosive weight in that building.

The other primary code is National Fire Protection Association (NFPA) Code 1124, which is the code for manufacture, transportation, and storage of fireworks and pyrotechnic articles. It mirrors the requirements of ATF, but it also has some additional best practices included in it. 

California does not adopt NFPA standards, and that's one thing that I've been advocating for as part of the Cal Fire General Fireworks Advisory Committee. We're in the round of making revisions to the Title 19 regulations and there have been a number of suggestions of specific clauses… that the NFPA provisions should be adopted in California.

It's been reported that this company and the facility had a valid state license, but the owner/CEO was denied a federal permit from the ATF. Yolo County officials also said the company had no local licenses to store fireworks on the property or a business license. Is that a red flag? 

This is a huge red flag. I'm completely perplexed by this. I don't know how you could have a state license for professional display fireworks and not have a valid ATF license. States are allowed to be more restrictive than the federal regulations, but they are never supposed to be less. And I think this is going to be an issue in front of the Cal Fire General Fireworks Advisory Committee. There are a number of us who are very passionate about closing this loophole. It should not exist. 

A June 6, 2024 aerial image of the Esparto fireworks storage facility that exploded July 1.Google Earth

Tell us about this Cal Fire advisory committee. What has this body been working on?

[For] the past couple of years we've been working on revisions to the fireworks regulations as well as some of the licensing requirements and also the fees. We've made great progress in moving forward on some revisions to the regulations. We have a meeting next month… I think this accident is going to be top of the agenda. Everybody wants to know how in the world something like this could happen. 

It’s early in the investigation, and the cause is currently unknown, but what do you think the industry could learn from this deadly explosion?

Compliance. Clearly, there was no real table of distance separating all of this material. The Occupational Safety and Health Administration (OSHA) regulations back in the late 1970s were modified for manufacturing because there was a significant accident out in Oklahoma, where the entire plant was destroyed and I believe like 27 people were killed.

The regulations were modified to separate everything so that if you're manufacturing, you can never have more than 500 pounds of pyrotechnic composition in a process building at one time. Never more than two people working in that building at one time, and then a table of distance separating all the buildings for storage. 

Everything has to be separated so you don't have the domino effect when and if something goes wrong. And we had the domino effect in Esparto, unfortunately.

You can hear Heckman’s full conversation with Vicki Gonzalez, along with analysis from fire and explosion investigator Richard Meier, here.