It was typically chaotic in the emergency room at Los Angeles County/USC Medical Center that February day in 1993. Richard May was treating patients in the triage area when a disgruntled man started ranting about the long wait. Then, without warning, the man pulled a gun and started shooting, hitting May in the head, chest and arm and seriously wounding two other doctors.

The carnage, coming after a series of violent incidents, prompted a wave of safety improvements, including the installation of metal detectors at hospital entrances, bulletproof enclosures in emergency rooms and the addition of more security guards.

Now, 20 years after the attack, officials want the metal detectors removed from parts of county hospitals to make them more welcoming to patients in the newly competitive marketplace being created by the Obama administration’s healthcare overhaul. The machines in the emergency rooms will remain, but the others are to be taken out by summer. The proposal comes at a time when high-profile shootings have put the nation on edge and prompted emotionally charged debates about the availability of assault weapons and the presence of armed officers in schools.

The county’s director of Health Services, Mitchell Katz, says metal detectors stigmatize poor patients and visitors and give the impression that the county facilities are dangerous. Security is paramount, but metal detectors aren’t the best way to ensure that, he argues. Most other urban hospitals in L.A. County do not have the machines, relying on guards to provide safety, he said.

“It is a different moment to look and ask ourselves, ‘What is the best way to do security?’” Katz said.

But the proposed changes have patients, nurses and doctors worried and are drawing opposition from law enforcement and union members.

May, 67, who suffers from post-traumatic stress disorder, is among those asking administrators to reconsider. He works part-time at the county’s Hudson Comprehensive Health Center south of downtown, where he says the metal detector gives patients and staff peace of mind.

“I feel angry, frustrated and resentful,” he said of the proposal to remove the devices. “We wouldn’t have been shot if they were there then.”

Paul Kaszubowski, 64, another doctor shot in 1993, said the bullet shattered his arm and grazed his head. He still suffers problems with his arm and has occasional flashbacks. Removing the metal detectors doesn’t make sense, he said. Providing compassionate and high-quality care is the best way to attract and retain patients, he said.

Beginning next year, uninsured patients will be eligible for Medi-Cal coverage and have more options outside of the county’s healthcare system. That is driving safety-net hospitals to improve their customer service so they are no longer the providers of last resort.

But that push is running headlong into a record of violence at urban medical facilities, where healthcare workers are often the victims of assault. Hospitals are intrinsically high-risk places, and metal detectors can help prevent violent attacks, said Jane Lipscomb, a University of Maryland professor who has studied hospital safety.

The county’s largest public hospital workers’ union is trying to stop the removal of the scanners and sent a letter to Katz saying the action is a “huge decision” that could put patients and staff in harm’s way.

Longtime County/USC nurse Sabrina Griffin, a union representative, vividly remembers the 1993 shooting and fears something similar could happen again if the screening equipment is removed. She particularly worries about gang retaliation spilling into the hospital after a shooting or stabbing.

“I just feel safer having the scanners,” she said.

Sheriff’s Department Capt. Chuck Stringham, who oversees security at the county healthcare facilities, said late Friday that the department is opposed to the wholesale removal of the metal detectors without another plan for weapons screening.

County hospitals mirror the crime and violence of surrounding communities, he said, and the scanners serve as the first line of defense — finding guns, knives, box cutters and other weapons.

The county removed the metal detector equipment from the outpatient building at County/USC in July, and no violent incidents have been reported there since doing so, according to the Sheriff’s Department. By June 30, the county plans to remove 26 more machines from County/USC, Harbor-UCLA Medical Center, Olive View Medical Center and the Martin Luther King and Hudson centers.

Patients and visitors entering another County/USC facility last week emptied their pockets of cellphones, keys and wallets before stepping through the scanners. In a period of a few hours, guards confiscated two pocketknives.

Walter Johnson, 59, who had an eye appointment, said removing the machines is “crazy.” “How would they know if anyone is coming in with a gun, or an AK-47, or a knife?” he said. “The minute you take these out, you are gonna give some idiot some excuse to do something.”

Michelle Mendez, an ER nurse, said metal detectors are needed in the emergency room but not elsewhere. “I think [visitors] would feel more comfortable when visiting their loved ones, knowing we aren’t so concerned about violence and crime and weapons,” she said.

Tammy Duong, a medical resident in the psychiatric unit, said the machines can be intimidating. But she worries about what might happen without them.

“Just because it is a hospital,” she said, “doesn’t mean violence can’t spill over.”

anna.gorman@latimes.com