SACRAMENTO -#8212; Imitation firearms like the one a 13-year-old boy was carrying when he was shot to death in October by a Sonoma County sheriff's deputy could no longer be made or sold in California under legislation that advanced Tuesday in the state Senate.

SB 199 would require BB, pellet and airsoft guns to be brightly colored or translucent so that they are not mistaken for the real thing.

"By passing this bill, we improve public safety. It's that easy," Sonoma County District Attorney Jill Ravitch testified at Tuesday's hearing before the Senate's Public Safety Committee.

Andy Lopez was shot and killed Oct. 22 after the deputy reportedly mistook Lopez's BB-style gun for an authentic assault rifle.

State law prohibits imitation firearms such as the one the teen carried from being displayed in public unless the weapon meets color guidelines. Federal statutes also require that weapons that expel plastic pellets, such as airsoft guns, be equipped with orange tips.

SB 199, co-authored by Sen. Noreen Evans, D-Santa Rosa, would take it a step further by requiring that all BB, pellet and airsoft guns made and sold in California be colored a certain way. Paintball guns would be exempted.

Evans testified Tuesday that Lopez's death was a "preventable incident."

"This young man would be alive today if this law was the law of the state of California," she said.

State Assemblyman Marc Levine, D-San Rafael, also spoke in favor of the bill, which advanced on a 4-1 vote over the opposition of the gun lobby, which successfully killed similar legislation in the past.

Ed Worley, the National Rifle Association's spokesman in California, described SB 199 as "overly broad."

Outside the hearing, Worley presented the bill as a de-facto ban on BB guns because "what boy wants a bright blue Daisy rifle?"

Sen. Steve Knight, R-Antelope Valley, who voted against the bill, said "orange or pink guns" would not help police when they are faced with a split-second decision whether to use lethal force.

"I would not evaluate the situation is 'OK' because I see a fluorescent gun," he said.

The debate highlights the challenges of defining what are variously called imitation, toy or copy-cat weapons, and how to apply a universal standard for their legal use.

As one example, federal law requiring "look-alike firearms" to be affixed with bright orange tips applies to airsoft guns, which expel plastic BB's, but not to "traditional BB" guns, which fire metal projectiles. Paint-ball and pellet-firing air guns also are excluded from federal restrictions.

California bans the manufacture and sale of "imitation firearms." BB devices, defined as those that expel a projectile no larger than six millimeters through the force of air pressure, gas pressure or spring action, are exempted from the ban, as are "spot marker guns."

However, state law defines BB devices as imitation firearms for the purposes of regulating their use.

Jay Snider, chief executive officer of an online airsoft gun retailer based in Southern California, testified Tuesday that the industry "recognizes improvement in the law is necessary to prevent future tragedies."

But Snider said outside the hearing that requiring airsoft guns to be entirely colored a certain way "would kill our industry."

Snider said that airsoft sales generate an estimated $100 million in annual revenue in California, which he said is home to nine of the nation's 10 largest airsoft retailers.

Snider said the airsoft industry is proposing that the orange tips on airsoft guns be bigger and that buyers be required to take an online education course about the weapon's proper use as a condition of purchase.

State Sen. Kevin de Le?, D-Los Angeles, the bill's other co-author, testified that he had a "productive" meeting with airsoft industry representatives last week.

De Le? introduced similar legislation in 2011 after police shot and paralyzed a 13-year-old Los Angeles boy carrying a BB gun modeled after a real handgun. That bill stalled in committee amid resistance from gun manufacturers and lobbyists.