LASER is an acronym that stands for Light Amplification by Stimulated Emission of Radiation. A laser produces an intense, highly directional beam of light, and its application is widespread from being used in optical disc drives, laser printers, barcode scanners, DNA sequencing instruments, cutting and welding materials, and in laser surgery and skin treatments. It may cause thermal-related tissue damage where the tissue proteins are denatured due to the temperature rise following absorption of laser energy. Hence, the human body is vulnerable to the output of certain lasers, and exposure can result in damage to the eye and skin. To ensure the safe use of laser protective equipment (e.g., eye protection) and materials (e.g., filters and barriers), ANSI Z136.7-2020: Testing And Labeling Of Laser Protective Equipment specifies recommendations for their testing and labeling.
What Is ANSI Z136.7?
ANSI Z136.7-2020 provides recommendations for testing and labeling laser protective materials and protective equipment, such as eye protection, barriers, curtains, filters, and windows designed for use with lasers and laser systems that operate at wavelengths between 180 nm and 106 nm. Since it is now widely accepted that the human eye is almost always more vulnerable to injury than human skin, an emphasis is given to ensuring adequate testing of laser protective eyewear (e.g., absorptive, interference/reflective, and hybrid filter technologies).
Testing procedures are provided in this American National Standard to ensure that the laser protective materials and equipment maintain their specified level of protection throughout the life of the products. Such protective devices include laser eye protective devices or instrument filters, laser window filters, and laser area protective barriers, screens, or beam blocking curtains. Depending on the protective device, laser type, temporal mode of operation, and wavelength(s), different test methods may be required. ANSI Z136.7-2020 aims to provide reasonable and adequate guidance on the test methods, protocols, and specifications for devices used to provide eye protection from lasers and laser systems.
To learn more about the ANSI Z136 Series for Lasers, check out Applications of Lasers that range from uses covered in other laser American National Standards like ANSI Z136.3-2018: Safe Use of Lasers in Health Care, ANSI Z136.8-2021: Safe Use of Lasers in Research & Testing, ANSI Z136.6 – Safe Use of Lasers Outdoors, and more.
How To Use ANSI Z136.7
Other special application standards, e.g., ANSI/ASSE Z87.1 Occupational and Educational Personal Eye and Face Protection Devices, will need to be used in conjunction with this standard to provide complete testing of laser protective materials. The recommended stepwise procedure for using ANSI Z136.7-2020 is as follows:
- Determine the type of protective equipment (device); eyewear, barrier, or window
- Determine the filter technology used; absorptive, reflective, or hybrid
- Determine the material type of eyewear/windows under study: material, metal, plastic, glass, hybrid, etc.
- Determine the appropriate laser or laser system: continuous wave, Q-switched, or sub-nanosecond, or some combination of pulse durations
- Determine the wavelength or wavelength band of the laser protection.
- Determine the specified optical density or barrier threshold level as identified by the manufacturer at the wavelength in question
ANSI Z136.7-2020: Testing And Labeling Of Laser Protective Equipment is available on the ANSI Webstore and in the standards package, ANSI Z136.1 and Z136.7 Combination Set.