Using lasers safely in a manufacturing environment requires plenty of planning, good training and constant vigilance. It all starts with the creation of a sound safety plan and, often, the appointment of a laser safety officer (LSO), as well as having the right protective equipment and signage.
The recently updated ANSI Z136.1 parent standard for the safe use of lasers as well as the newly created Z136.9 standard “Safe Use of Lasers in Manufacturing Environments” provide the foundation for keeping employees safe. Safety courses based on those standards are vital to learning how to avoid beam and non-beam hazards.
Gus Anibarro, education director for the Laser Institute of America, has trained hundreds of laser users and LSOs. He has fielded plenty of calls that begin with the words, “We’re getting new lasers and we know they are a hazard — what do we do?” But no matter your level of experience with industrial lasers, there’s always something new to learn.
So you bought a laser
You’ve taken the plunge and added the power and precision of a laser to your repertoire of services. Now what? The first thing to do is determine the class of the laser, Anibarro instructs. “The class will dictate the kind of safety program you might need.” Class 3B and Class 4 lasers require the most protections. But there are exceptions.
“If you have a Class 1 system, you pretty much don’t need anything,” he explains. “You don’t even need an LSO — unless you have a third party come in to service and align the laser system and that person would defeat the interlocks and or perhaps remove a portion of the enclosure. At that point you would need an LSO because the third party would have to comply with your standard operating procedures.”
In the case of a Class 3B laser, which might be used for measuring and sensing but not cutting, welding or drilling: “Usually the beam will not be enclosed; it could be, but it doesn’t have to be,” Anibarro explains. “The 3Bs I’ve seen have been on production lines, and the beams have been open. The ANSI standard says they need to have a laser safety officer.” If a sensing laser is Class 3R or lower, “there’s really no worry; you don’t want to look at the beam, but you don’t need an LSO. You will want to minimize reflective surfaces.”
In one recent instance, Anibarro heard from a facility installing a Class 4 system. One of the first questions to answer in such a case is if there is proper machine guarding. In this case, the guarding was limited, “so there was potential to be exposed to the beam” — and an LSO was required.
Once a facility determines that an LSO must be named, the next step is to train that person how to conduct a hazard analysis and create, implement and monitor a laser safety program.
Comply with regulations
After having established the class of your laser system(s), determined whether or not you need an LSO, and committed to an effective safety plan based on the ANSI standard relevant to your work environment, the next step is knowing what state and federal regulations apply to your operation.
At the federal level, the Occupational Safety and Health Administration (OSHA) “doesn’t have very many regulations for lasers other than in the construction industry,” Anibarro notes. (LIA has been part of the OSHA Alliance Program since 2005, providing laser-safety information and training OSHA compliance officers and consultants.) But “if you have a Class 3B or 4 laser and OSHA inspects your facility and finds you don’t have a laser safety officer, they could cite you under the general duty clause.”
Meanwhile, some states have numerous laser regulations — others don’t. Typically, your primary obligation is registering your laser system(s) with your state’s radiation control program. Check with your state’s bureau of radiation control to determine the protocol that applies to you, Anibarro advises.
In Florida, for example, “you have to register all Class 3B and 4 laser systems with the state,” Anibarro explains. “On your registration form, you have to tell them who your LSO is, then look at the administrative code and see what that code requires. Typically, the code follows the ANSI standard. If you’re in compliance with the ANSI standard, then more than likely you’ll be in compliance with the state regulation.”
Other states requiring registration of lasers include Arizona, Georgia, Illinois, Massachusetts and Texas. But states like California and Wyoming require no registration.
Registration fees vary, too. In Florida, Anibarro notes, there is no charge to register, but there is in Texas. And as with OSHA, states like Illinois that have the manpower to perform inspections of facilities using lasers could levy fines if those lasers aren’t registered or an LSO isn’t on the job.
Beam and non-beam hazards
After your laser safety program has been in place for six months to a year, it might be advisable to ask an outside consultant to perform an audit to ensure continued compliance with ANSI standards, Anibarro says.
While working to prevent obvious beam hazards that can severely damage eyes and skin, LSOs must also stay on top of non-beam hazards — like the rupture and propulsion of an unsecured cylinder of compressed gas used in conjunction with a laser. And “if what is inside a tank is some inert gas and it gets out, that gas could displace the breathable air in the room,” Anibarro warns. “If you can’t get out fast enough or you’re not aware it’s happening, you could asphyxiate.” And if the gas is a corrosive one, like fluorine, it could burn a user’s lungs. Meanwhile, a flammable gas like methane could be struck by a stray beam and ignited. A safety program should provide for gas detection and safety cabinets in which to store these gas cylinders.
Sometimes, a laser creates potentially hazardous smoke when cutting, drilling, welding or marking. “The ANSI standard says it has to be controlled,” Anibarro notes, “and the main method of control is smoke evacuation. The evacuator system has to be filtered, and the filters have to be cleaned periodically — especially if combustible dust is produced.” If the filtration system is not cleaned regularly, the filters might clog — and static electricity could spark an explosion.
Lasers mounted on robotic devices present risks, as well. “Sometimes workers have to teach the robot where to cut or weld,” Anibarro explains. “These laser systems have coaxial beams that are visible; the visible beam is used to help the robot target the invisible beam that is cutting or welding.” If someone programming the robotic device has to go inside the laser cell to calibrate the equipment, he or she might be exposed to a Class 3B aiming beam — and must wear eye protection to avoid injury.
In terms of skin injuries, the most notable “are holes through fingers and third-degree burns,” Anibarro indicates during his presentation on safety basics at the Lasers for Manufacturing Event. “I have heard of amputations when people have accidentally put their hand in the path of a beam. I have heard of people (who have) gotten a best-buy date marked right into their forearm.”
Get with the program and get trained
Ultimately, a laser safety program need not be overcomplicated, Anibarro asserts. “You need to follow some safety protocol, but it doesn’t have to be elaborate but it should be based on a national consensus standard.”
Even if a shop has one completely enclosed Class 1 laser but will be hiring someone else to repair it, “somebody, even if it is the owner, should get basic laser safety training.” But while a mom-and-pop job shop might fly under the radar in terms of OSHA scrutiny, having a trained LSO well versed in beam and non-beam hazards of Class 3B and 4 laser systems is a good insurance policy against potentially costly fines and lawsuits. Armed with knowledge of your laser class and its nominal hazard zone (discussed in the safety portion of your laser’s literature), you can then decide what level of training is best for your personnel.
If you know the nominal hazard zone — 10 feet, for example — LIA’s two-day industrial LSO course should suffice, Anibarro says. But what if you don’t know the nominal hazard zone of a laser in the middle of your shop floor? Could that laser beam bounce off something and shoot out of the cabinet? How far could it travel and still cause injury? What if you can’t determine the hazard zone with the laser literature from the manufacturer? “You might need to do a calculation; in that case, you would take LIA’s four-and-a-half-day LSO with hazard analysis course,” Anibarro advises.
Most LSOs don’t need to perform hazard calculations, especially if their system is enclosed. An open-beam system might have limited machine guarding that could allow the beam to reflect out. In that case, the laser’s operating information might provide the hazard distances at different laser powers.
You can receive expert training in a classroom, online or even invite an educator to hold a course at your facility. Make sure the course is based on the appropriate ANSI standard (LIA provides a copy to each of its students) and covers equipment like curtains, barriers and eye protection; tools to measure and detect a beam (CO2 and Nd:YAG beams are invisible); and provides a certificate of completion.
The Laser Institute of America has served as the foremost authority on the safe use of lasers since 1968. LIA, secretariat of the ANSI Z136 laser standards, provides a full range of novice-to-expert training for laser users and LSOs. To learn about the full range of classroom, on-site and online training offered by LIA, visit https://www.lia.org/education