20 Years of Laser Safety: From VBG 93 to OStrV & TROS

For almost 20 years, I have been working as an instructor in the field of laser safety. Twenty years in which a great deal has changed. Twenty years in which a lot has happened. And after 20 years, I can say that, for once, something has genuinely improved.

This concerns laser safety in industrial environments, particularly with regard to visible lasers such as line lasers, cross-line lasers and point lasers. For the time being, I would like to exclude laser projectors from this discussion, as a laser projector, unlike the laser types mentioned above, is equipped with a beam deflection system that moves a single laser beam. During retinal exposure, this produces so-called "single pulses" as well as a "pulse train", which must essentially be treated differently from exposure to continuous-wave lasers, such as line lasers or cross-line lasers. With these lasers, the projected pattern, such as the laser line, is generated by fixed optics rather than by a dynamic beam deflection system. This is a major difference!

As early as the 1970s, the predecessor of EN 60825-1, the standard for the "Safety of Laser Products", was published in the form of DIN 57836. In 1986, this was converted into VDE 0837. Since 1993, this VDE standard has been available as a European safety standard. The current version referred to here is the 2014 edition published in July 2015.

Corresponding to this standard, the accident prevention regulation "VBG 93" was published in 1988. It significantly expanded the requirements for handling laser products and laser installations and, as the name suggests, focused particularly on accident prevention. Although still relatively basic compared with today's OStrV and TROS regulations, this accident prevention regulation was already pioneering and restrictive in terms of the handling and public operation of lasers. For the first time, laser installations and laser products were subject to specific regulations.

In 2007, BGV B2 was published together with accompanying implementation instructions. It incorporated and further developed the knowledge and experience gained during the preceding years. Even at that time, however, I felt that these provisions were not sufficiently detailed and still left considerable room for interpretation, which was extensively used by various parties.

In 2010, the OStrV, the German "Occupational Health and Safety Ordinance on Artificial Optical Radiation", was published. This short, seven-page publication was more of a summary and general source of information, as the requirements were still relatively basic. It was not until 2015 that the OStrV was supplemented by the TROS, the "Technical Rules on Artificial Optical Radiation", a very comprehensive and advanced collection of detailed descriptions and requirements relating to various laser installations.

Step by step, I will discuss some of the current regulations, particularly with regard to the use of line lasers and cross-line lasers, which have since been given a justified special status within the TROS.