ULS Blog

7 Safety Questions to Ask Before Purchasing a Laser System

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May 2019

As laser cutting, engraving and marking systems become more common for business and educational use, it can be easy to assume that manufacturers have taken precautions to make their products safe. But with different laser safety standards all over the world, it is smart to take a closer look to make sure the system is really safe for your intended use and environment. If you buy a system without assessing safety, you could end up with property damage or severe user harm.


As a laser system owner, you are responsible for meeting all workplace safety requirements for operation. Failure to follow local and federal regulations or otherwise ignore safety obligations not only puts employees at risk, but it also can increase your liability in the case of an accident. Even if you unknowingly bring an unsafe laser system into your facility, you may be found guilty of negligence.

Some helpful resources to make sure your laser system complies with U.S. federal regulations are the ANSI Z136 Series and the FDA 21CFR1040.10 and 1040.11 standards. State level regulations vary widely, although many reference ANSI Z136. In Europe, the IEC provides internationally recognized laser standards including 60601 and 60825. However, it is important to note that specific regulations vary by location.



We always recommend doing your own research, but to get started, here are 7 questions that can help you evaluate safety before purchasing a laser system.



1. Is the laser system properly labeled?






One quick indicator that a system not meeting basic safety regulations is if it does not display the required safety labels. U.S. and International regulations require that all laser manufacturers place warning labels in specific locations on the system to indicate particular hazards. If a system does not have proper safety labels it does not meet minimum safety requirements and should not be used.


2. Does the design include a metal enclosure?




Class 1 laser systems should be designed to contain any stray laser energy to prevent user exposure and injury. According to industry standard, laser-safe enclosures are constructed from metal thick enough to prevent laser beam penetration. You should avoid systems made from plastic, because they cannot effectively prevent the beam from burning through the enclosure and causing significant harm.

3. Does the enclosure have labyrinth seals?













In addition to the enclosure material, you should make sure all enclosure doors or access panels have overlapping flanges to prevent direct line of sight into the enclosure. These “labyrinth seals” are necessary to prevent any laser energy from escaping. Systems without these flanges cannot truly be considered laser-safe. So, be sure to check all enclosure openings.


4. Are there redundant interlocks on operation doors and access panels?




According to all major international standards, Class 1 laser systems are required to have redundant interlock mechanisms on all doors and access panels used in operation. These interlocks stop the laser from firing when a door is opened. This essential design feature helps ensure safe operation and avoid exposure to laser radiation.

5. Is the viewing window made of laminated safety glass?













While plastic viewing windows meet the minimum requirements for laser safety, they are not as safe as laminated glass. If a stray laser beam makes direct contact with a plastic window, it can quickly burn through and escape the enclosure.

For CO2 lasers, laminated safety glass with an optical density of 6+ is recommended. The glass should have a minimum of two layers with a film in between to keep the glass intact even if directly struck by a laser beam or heavy object. Tempered glass is not safe, since it can shatter into small pieces, allowing laser energy to escape.

Systems with a fiber laser source should have an additional protective layer, usually tinted blue or green, to contain fiber laser radiation, which is particularly damaging to the eye if viewed directly. If you are not sure what to look for, you can ask the manufacturer for a window safety certification for all laser sources included with the system.


6. Does it have a high temperature alarm?




Because your material may be combustible, another important safety feature to look for in a laser system is a high temperature sensor and alarm. If an unusually high temperature is detected in the laser processing area, the system is designed to shut down the laser source and trigger an audible alarm. Be sure to double check with your manufacturer as this feature is not a mandated requirement. For added safety, some laser systems can be configured with an optional fire suppression feature. While these safety features are helpful, it is important that you never leave your laser system unattended during use and monitor it for safe operation.

7. Is the laser source air-cooled with low voltage power supplies?




Despite safety concerns, there are many low cost systems that use glass laser tubes, which are powered by high-voltage direct current and cooled with water. Basically, cool water is circulated around the glass laser to keep it from overheating.

In the case of water leakage, damage to the glass laser tube, or direct contact with any of the high-voltage elements, there is a serious risk of electric shock. With voltages in excess of 25,000 V and currents ranging from 30 to 150 mA an electrical shock can be lethal. Careful consideration should be taken before purchasing a laser system built with high-voltage glass lasers in any environment, but particularly in schools. The safe choice is an air-cooled laser system with a low-voltage power supply.

Evaluating Laser System Safety




Before purchasing a laser system, be sure to get answers to these 7 safety questions, as not all manufacturers follow the same safety standards. In addition, you will need to assess safety based on your environment and how you plan to use your laser system. Research and review your federal and local laser safety regulations to understand the requirements and make sure your system is in full compliance. Remember, you are ultimately responsible for meeting all safety requirements and for safe operation of any laser system you buy.