To handle pyrotechnics on a movie set in California, you need a license, which requires five letters of recommendation, two years of apprenticeship, and passing a written test.

But to be an armorer, all you need is a background check. And in other states, you don’t even need that.

“There’s no actual rules,” said Joe Martinez, who works as an armorer in Hollywood. “There isn’t any official anything.”

The “Rust” tragedy, in which cinematographer Halyna Hutchins was killed by a live round in New Mexico, has prompted calls for industrywide reform. Some, including a California state senator, have advocated banning “real” guns — that is, guns capable of firing a live round — from sets entirely.

But others in the industry have suggested that would be impractical, and pointed instead to imposing some credentials to work as a film armorer.

“I do agree with permitting,” said Scott Rasmussen, a film armorer based in Albuquerque. “I think we should have a course to put people through, so they do know how to handle firearms.”

Given the scale of the tragedy, some kind of new regulatory scheme feels almost inevitable. New Mexico Gov. Michelle Lujan Grisham called this week for the film industry to adopt “comprehensive new safety protocols to ensure this kind of incident never, ever happens again.”

“If that sort of comprehensive new approach does not materialize,” she said, “the state of New Mexico will take immediate action, throughout whatever means are available to us, to ensure the safety of all personnel on all film and television sets here in our state.”

Hollywood has proved adept at regulating itself before government gets the chance. In 1983, following the deaths of actor Vic Morrow and two child actors on the set of “Twilight Zone: The Movie,” a joint labor-management committee adopted a slew of “safety bulletins” to prevent future tragedies. There are now 44 of them, covering everything from firearms on set to the use of hot air balloons and venomous reptiles.

Several armorers have made the point that if protocols are not followed, as they appear to have not been on the set of “Rust,” adding more rules will not make much difference.

“The guidelines have kept the industry very safe,” said Larry Zanoff, an armorer at Independent Studio Services in Los Angeles. “When you have professional people doing a professional job, these kinds of things should not happen.”

But when it comes to the qualifications to become a professional armorer, there aren’t many rules to break.

The armorer on “Rust,” Hannah Gutierrez Reed, is 24 years old, and was working as a film armorer for just the second time.

If she were working on a union project in California, she would have to be a member of Local 44 of the International Alliance of Theatrical Stage Employees, and she would have to take a gun safety class through that union. A similar rule applies in IATSE Local 52, the local that represents prop workers in the New York area. According to people who have taken the class, it is fairly rudimentary, and there is no requirement for continuing education.

IATSE Local 480, which covers New Mexico, does not require a gun safety class, according to workers familiar with the union, who added that Gutierrez Reed was also not a member of that union. Local 480 did not respond to multiple requests for comment, and her attorneys also declined to comment.

In California, she would also need an entertainment firearms permit. But that permit, which is issued by the state attorney general’s office, requires nothing more than a fingerprint-based background check, proving that the applicant is not a felon. The permit exempts entertainment armorers from certain gun control laws — like a 10-day waiting period and a limit on purchases — but does not require proof of competency with firearms.

In other states, including New Mexico, no such permit is required.

Armorers occupy a relatively small niche of the industry, and tend to build their careers through informal apprenticeships and word of mouth.

Often, a propmaster will also take on the job of armorer on set. Rasmussen was offered both jobs on the set of “Rust,” but turned it down, telling the production that it would entail too much responsibility for one person. He offered to serve solely as the armorer, but the production never got back to him.

Rasmussen argued that the job should be separated from the props department, and become its own licensed classification.

“Everybody who would be a weapons handler would have to demonstrate their knowledge of firearms,” he said. “Where they’re lacking, we would train them. And then you get your permit or your license to be a weapons handler.”

Some believe that a national standard would be better than trying to address the issue state-by-state. Such a standard would have to come from the industry itself, rather than the government.

“I think that improvement in a national training standard is probably to everybody’s benefit,” Zanoff said, “so no matter what set you’re on, the procedures are all the same.”

Two days after the “Rust” shooting, California State Sen. Dave Cortese proposed a ban the use of live ammunition, or guns that can fire live ammunition, on set. New York State Sen. Kevin Thomas followed with a bill to ban the use of live ammunition on sets — which is an extreme rarity — while also mandating gun safety training for everyone employed at a film studio.

Cortese has yet to introduce his legislation, and is not likely to until the next legislative session begins in January. In an interview, Cortese said he is still gathering input from IATSE officials on the best way forward.

“I want to hear from the armorers,” Cortese said. “Until we get their input, and feel like we have understood fully how they would go about this, we’re not going to finish writing this bill.”

Some are not waiting for a new law. The executive producer of ABC’s “The Rookie” has already announced that the show will no longer use guns that can fire live rounds, opting instead for prop guns that can be enhanced with post-production effects. On Wednesday, Dwayne Johnson announced that projects from his Seven Bucks Productions will no longer use real guns. But some argue that such prop guns are not realistic enough, especially for close-ups, or that the non-firing replicas do not come in enough models.

“There’s always going to be this temptation to use what is readily available in the U.S., which is real firearms,” said Kevin Inouye, a fight choreographer and the author of “The Theatrical Firearms Handbook.” “The economic fact is, right now, real guns are cheaper and are made a lot better than a lot of the non-guns that Hollywood uses.”

Others argue that the fundamental problem is that crews are stretched thin due to the intense demand for content, which can lead productions to cut corners.

“We have a bit of a problem with producers who put more emphasis on their product than their crew,” said Amos Carver, a stunt coordinator based in Tucson, Ariz. “If they would care more about the people than the project, then all of a sudden some pretty basic things come into focus.”