Lasers were conceived in science fiction, but it was in real-world research environments where they germinated. With a medley of laser applications serving a variety of industries these days, the value of lasers in research environments is still emphasized, as they help drive the industry. To protect professionals working in research, ANSI Z136.8-2021: Safe Use Of Lasers In Research, Development, Or Testing provides adequate guidance for the safe use of laser systems.
An Early History of Lasers
Inhabitants of the 21st Century might not grasp the genesis of the technology that simplifies their daily lives. Great minds in laboratory or research environments realize new technologies, but many are devised by science fiction creators. Sending a spacecraft to the moon, radio broadcasts, robots, Bluetooth technology, video calling, augmented reality, and even rideshare services appeared in science fiction stories long before our world.
Many speculative technologies in forward-thinking imagined worlds sparked interest in their scientific development. In War of the Worlds, H.G. Wells details invading Martians wielding a heat ray—essentially a modern CO2 laser. This late 19th Century depiction of the potential technology, paired with the succeeding discovery of radio, X-rays, and radar drove interest in optics and amplifying radiation throughout the first half of the 20th Century.
In 1954, Charles Townes obtained the first amplification and generation of electromagnetic waves by stimulated emission. He and his students coined the word “maser” for the device, standing for “Microwave Amplification by Stimulated Emission of Radiation. In 1957, Townes and his colleague (and brother-in-law) Arthur Schawlow concluded that you could more easily amplify radiation with short waves rather than far-infrared waves, with Schawlow uncovering that you could put the atoms you wanted to stimulate in a long, narrow cavity with mirrors at each end—an arrangement used by generations of optics researchers.
In the late 50s, Gordon Gould conducted research to uncover the many options possible with a concentrated beam of light, and he realized, while using the same arrangement as Townes and Schawlow, you could accomplish something beyond the “infrared maser.” He named the then-undiscovered device a laser (“Light Amplification by Stimulated Transmission of Radiation”).
These three, in theory, understood how to create a laser. However, lasers didn’t enter the real world until 1960, when Theodore Maiman created the world’s first laser by placing a ruby inside a helical-shaped lamp.
Early Usage of ANSI Z136.1
Reflective of the environment through which lasers first emerged, back when the first edition of the American National Standard for the safe use of lasers, ANSI Z136.1, was published, almost all lasers were found in research laboratories. Work on the development of this standard began in the late 60s, and, as laser technology burgeoned and spread to support other industries, standards for laser safety broadened as well. Since this time, ANSI Z136.1 has become a horizontal standard, with the current edition, ANSI Z136.1-2014: American National Standard For Safe Use Of Lasers, providing broad requirements for laser safety.
Specifically, ANSI Z136.1 addresses laser classification, definitions and background information, maximum permissible exposure values (MPEs), and laser safety officer (LSO) responsibilities. You can learn more about this standard in our post ANSI Z136.1-2014: Safe Use of Lasers.
About ANSI Z136.8-2021
Industry-specific requirements, like those for lasers in research environment, are outlined in vertical standards such as ANSI Z136.8-2021: Safe Use Of Lasers In Research, Development, Or Testing. This American National Standard provides users with guidance and recommendations for the safe use of lasers and laser systems used to conduct research, development, or testing primarily in an indoor setting. It applies to lasers/laser systems that operate at wavelengths between 180 nm ultraviolet (UV) and 1 mm (1000 μm) infrared (IR). Use of this standard requires an assigned laser supervisor or LSO.
Testing environments might deviate from normal laser operations, possibly requiring access to levels of laser radiation higher than the accessible emission limits (AEL) from the assigned laser class. Safety with these considerations in mind is accomplished by first classifying the lasers to their relative hazards and then specifying control measures based upon those hazards and conditions of use.
ANSI Z136.8-2021 outlines hazard evaluation, control measures, education and training (including LSO and on-the-job training), medical examinations, and some non-beam-related hazards. In this standard, testing includes not only the operation of lasers and equipment, but also the verification of the overall functionality of the lasers and laser safety features and the measurement, evaluation, or assessment of any properties and parameters of the laser radiation.
Relationship Between ANSI Z136.1 and ANSI Z136.8
Since ANSI Z136.8-2021 is an application-based standard, it is supported by ANSI Z136.1 requirements. It and other vertical standards may deviate from the requirements of the main laser safety standard. When this happens, as stated in ANSI Z136.1-2014:
“Each deviation is valid only for applications within the scope of the standard in which it appears. Guidance in specialized standards, for example, ANSI Z136.3 (latest revision) and ANSI Z136.4 (latest revision) that appear to conflict with the requirements of this standard, shall have precedence within the scope of that standard”ANSI Z136.1-2014
The LSO determines which, if any, specialized standards like ANSI Z136.8-2021 are applicable. If you’d like to learn more about the relationship between vertical and horizontal standards published by the Laser Institute of America (LIA), please refer to our post Vertical and Horizontal Standards – What?!
ANSI Z136.8 and ANSI Z136.1 are available together as the ANSI Z136.1 and Z136.8 Combination Set.
Further LIA standards are discussed in Applications of Lasers.