Projects concerning optical radiation

The unit takes up topical research issues from the field in order to examine them more generically and to develop solutions that are then available to a wider public. This, too, includes obtaining information on the exposure of workers to optical radiation.

IFA Project 4144: Emission of optical radiation by gas torches

Gas torches are frequently used in glasswork for the heating of glass workpieces. The gas flame of these torches emits radiation in the optical (ultraviolet, visible and infrared) wavelength range to which the workers may be exposed. The results of the project have been presented comprehensively in an IFA Report (in German).

IFA Project 4206: Skin cancer caused by UV radiation

Exposure to ultraviolet radiation is without a doubt the biggest risk factor for the contraction of non-melanocytic skin cancer such as actinic keratoses, squamous-cell carcinomas and basal-cell carcinomas. A software application was developed for recording workers' case history in conjunction with the accident insurance institutions. The application implements the requirements of the (German) IFA technical information document (PDF, 351 kB) concerning the handling of cases of skin cancer caused by UV radiation, and is now employed routinely by the accident insurance institutions. Measurements in the sister projects employing GENESIS-UV have now also permitted comparison between measurement and calculation, the associated creation of a job-exposure matrix, and further development of the criteria for the assessment of cases of occupational disease BK No 5103. The results obtained by the DGUV and its medical research partner bodies in project FF-FB181 will be published in the near future by the DGUV.

IFA Project 4207: Creation of the GENESIS measurement system

Measurement of workers' exposure to various noxious influences is particularly difficult when data must be recorded over longer periods (e.g. months). Constant surveillance of the technology, data transfer, management of the technology, and the downstream databases entail a considerable overhead when they are all needed at the site of measurement. In times of under-staffing, it is virtually impossible to complete large-scale comparable measurement studies. The aim is for a system to be developed that solves the above problems. The GENESIS measurement system is designed to fulfil two essential tasks:

  • Decentralized long-term measurements at the test subjects' work location
  • Collection of data from all over the world at a single collecting point

GENESIS provides the IFA with a measurement system that can be used to conduct large-scale decentralized measurement campaigns. Since 2014, the efficacy of this system has been demonstrated in the form of GENESIS-UV.

IFA Project 4208: UV transmission of vehicle windows

The exposure of vehicle occupants to ultraviolet radiation is dependent upon factors including transmission of the radiation by the vehicle's windows. Vehicle windows take different forms: whereas up to the early 1990s, full-glass windows were fitted, laminated products have been used since then, at least for windscreens. The plastic film used in these products absorbs a considerable proportion of the ultraviolet radiation. The UV transmission of vehicle windows was measured at a number of sites, namely the scientific collection of defence engineering specimens (Wehrtechnische Sammlung, WTS) in Koblenz, the museum of postal vehicles in Heusenstamm, and in Ulm and Tönisforst. The apparatus developed in the project was used for testing. This apparatus permits reproducible measurement on windows of different curvature. The results can be found in an IFA informative publication (PDF, 152 kB).

IFA Project 4209: UV reflections during welding

UV exposure of welders and their assistants is dependent essentially upon the radiation emitted by the welding arc. Considerable exposure may however arise from reflections, as well as from direct radiation. It is therefore not sufficient for protection to be provided against direct radiation alone during welding work. In addition, welders' assistants are often much less well protected than the welders themselves. The aim of the project was to study the reflection of UV radiation on a range of surfaces. Overall, reflection was found to be in the order of 0.2 to 1.2%. A relationship was demonstrated between the reflected radiation components and the reflecting surface. The material of the surface was a factor here, as was its colour. Some surfaces (such as a fire blanket and highly reflective Silverice plates) exhibited increasing reflection with rising wavelength, whereas no relationship between wavelength and reflection was observed for the standard welding curtains.

IFA Project 4210: UV radiation emissions during oxyfuel gas welding

A number of different welding methods are used according to the application. These methods range from oxyfuel gas welding, through stick electrode welding, to new forms of pulsed methods, e.g. cold metal transfer (CMT). Whereas arc welding methods have been studied relatively comprehensively, data are still unavailable for oxyfuel gas and pulsed welding methods. Study of the oxyfuel gas welding methods showed UV radiation exposure to be a result of gas combustion, and shadowing by the workpiece to result in reduced exposure. The results of IFA Project 4144: "Radiation emissions from gas torches" can be transferred directly. The results of the measurements conducted on the new CMT method revealed no systematic increase or decrease in the irradiation values attributable to the use of this method. Differences were observed according to the welding methods used, e.g. metal active gas (MAG) or tungsten inert gas (TIG) welding.

IFA Project 4218: Exposure to radiation from stage lights

During the performance of stage productions, actors and the stage as a whole are illuminated by means of stage lights. High-power lights may be used for this purpose, which in some cases take the form of spotlights aimed directly at the actors, and tracking them. Besides visible light, these lights also generate an ultraviolet (UV) radiation component that can present a hazard. The exposure to blue light must also be assessed. The stage light configuration in theatres is dependent upon the size of the stage and also upon the type of production that is being performed. A range of lighting situations and tests also arise during regular rehearsals. It has been found that the exposure limits for protection against UV radiation are observed. A new method must however be developed for assessment of the exposure to blue light. The methods used in the past have been found to be unsuitable when multiple stage lights are used, since selecting such multiple light sources as targets was not possible for geometric reasons.

IFA Project 4221: GENESIS-UV and meteorology

The weather is a decisive factor with regard to exposure to ultraviolet (UV) radiation. To date, no scientific studies have been completed in which measurements of the UV exposure radiation of individuals by means of dosimeters were cross-referenced to meteorological data.

The objective of this research project is to compare the results of measurements – performed with GENESIS-UV over many years – of the workers' exposure to UV radiation with meteorological data and to answer as-yet unanswered questions. This particularly concerns the UV index, which is to be examined for use by the accident insurance institutions as a possible prevention tool. The UV index is a measure of sunburn-inducing radiation on a flat surface. The project is also to examine whether shadow components can be estimated from measurements obtained with GENESIS-UV for work or periods spent inside or outside buildings.

IFA Project 4227: "UV radiation exposure during tasks performed outdoors" measurement campaign employing GENESIS-UV

People working outdoors are exposed to solar UV radiation. In Germany, some two to three million workers are believed to spend over 75% of their working hours outdoors. This definition of "outdoor workers" is arbitrary; workers are subject in some cases to considerable radiation exposure even below this threshold.

The purpose of this project is the performance of measurement campaigns by which the occupational UV radiation exposure of workers during their working time outdoors can be measured. Since this issue is of great interest internationally, cooperation with foreign partners is desired.

IFA Project 4228: Evaluation of the results of the "UV radiation exposure during tasks performed outdoors" measurement campaign employing GENESIS-UV

When large-scale measurement campaigns are conducted encompassing numerous occupations and tasks, structuring of the information relevant to work and tasks is problematic. On the one hand, it must be ensured that an adequate body of data is obtained for each group of persons studied; on the other, the merging of workers into groups for evaluation must not lead to the underlying task-related information being over-generalized. The latter presents the risk that the value obtained for a certain occupational or task group is no longer suitable for practical application.

As yet, no coding system exists for the exposure of workers to solar radiation during outdoor work. Since the measurements with GENESIS-UV (IFA Projects 4207, 4221, 4227) are precise down to the level of the sub-tasks, however, a new coding system must be created. This coding system should be multi-level, in order to permit interfacing at the topmost (occupational) level to OMEGA (the German system for recording, organizing and use of measured data for workplace exposure to hazardous substances) or ISCO (International Standard Classification of Occupations).


Marc Wittlich

Division 4: Ergonomics, Physical environmental factors

Tel: +49 2241 231-2862
Fax: +49 2241 231-2234

Benjamin Strehl, B. Sc.

Division 4: Ergonomics, Physical environmental factors

Tel: +49 221 231-2603
Fax: +49 221 231-2234

Martin Schmitz

Division 4: Ergonomics, Physical environmental factors

Tel: +49 2241 231-2505
Fax: +49 2241 231-2234