Analysis and interpretation of the results of the measurement campaigns employing the GENESIS-UV measurement system

Status:

completed 03/2019

Aims:

When measurement campaigns are conducted on a large scale and encompass numerous occupations and tasks, structuring the information relevant to work and tasks presents difficulties. An adequate body of data must be obtained for each group of test persons; at the same time, the merging of test persons into groups for evaluation must not lead to the underlying task-specific information being over-generalized. The latter presents the risk that the value obtained for a certain occupational or task group will no longer be suitable for use in the field.

No coding system of this kind existed before now for the exposure of workers to solar radiation during outdoor work. Since the measurements taken with GENESIS-UV (IFA Projects 4207, 4221, 4227) are precise down to the level of the sub-tasks, however, a new coding system had to be created. This coding system was to be multi-level, in order to permit interfacing at the topmost level (that of the occupation) to OMEGA or an international code (International Standard Classification of Occupations, ISCO).

Furthermore, no automated evaluation routines existed at the IFA suitable for processing the anticipated large volumes of data from the GENESIS-UV measurement campaigns.

The objective of the project was to create a new coding system, develop interpretation routines, and analyse the data obtained from the GENESIS-UV measurement campaigns performed in the course of IFA Project 4227.

Activities/Methods:

GENESIS-CODE was to be developed in a number of stages. The German Social Accident Insurance Institutions ultimately had to develop task profiles for each occupation studied. These task profiles had to be suitable for linking to the measured data.

In addition, routines had to be developed that would enable the raw data to be fed automatically into a database. In this step, the raw data were also to be processed directly with regard to longitude, latitude and the position of the sun. The data would then be available for scientific interpretation.

Scientific interpretation includes development of a workflow for further processing of the data.

All routines for automated interpretation were to be developed in consideration of other possible campaigns or issues, thereby ensuring their suitability for transfer.

Results:

Approximately 1,000 test persons from the most diverse of occupations took part in the measurement campaigns (see Project IFA 4227). The details of the test persons' occupations must be classified and harmonized in order to permit evaluation on a group basis. GENESIS-CODE comprises three levels to enable the tasks to be classified with respect to the associated exposure to solar radiation. The topmost level is the occupation, which is based upon other lists of codes (such as OMEGA or ISCO). Each occupation may encompass several task sub-groups, which in turn are defined by a series of sub-tasks to which solar exposure is relevant. An example is that of "Gardener, general (OMEGA 510)", which comprises several sub-task groups including "Ornamental gardener", "Arborist/tree climber" and "Nursery gardener". Each test person was assigned to a task profile structured in this form.

The measurement data obtained in one-second cycles were processed and analysed in a clearly specified sequence. The raw data were first recalibrated, by means of a routine supplied by the manufacturer, in consideration of the solar radiation spectrum and the latitude and longitude. The data were then categorized. Each measurement day was examined and inspected for this purpose. Following technical and scientific examination of the data, they were compiled in the course of interpretation to form daily and half-hourly exposure values. This procedure was followed on all levels of GENESIS-CODE. The reference to the test person was transferred to the relevant level and the data were cumulated.

Monthly mean values per day were formed from the daily exposure values as part of a descriptive statistic, as were monthly mean values per half hour. Finally, annual exposure values were extrapolated from these values.

Around 3.7 billion data records from 1,000 test persons were acquired by means of GENESIS-UV in the period from 2014 to 2018. This corresponds to 45,815 daily values in the highest category (1,254,075 half-hourly values). Altogether, 95 occupations comprising 172 sub-task groups and 646 sub-tasks were analysed and made available for subsequent use in prevention activity.

With respect to the occupations, UV radiation is distributed over a very wide range of values: from 38 SEDs per year (SED: standard erythemal dose; 1 SED = 100 J/m² of erythemally weighted radiation) for specialist restaurant employees or waiters/bartenders to around 1,000 SEDs for track construction workers. Some of the occupations in the building trade or raw materials extraction sector lie within the range between 500 and 700 SEDs; this represents the highly exposed range.

To enhance the validity of the data, the number of hours of sunshine in Germany in the years of the survey was analysed, and a comparison also drawn between exposure within an occupational group in Northern, Central and Southern Germany. One year (2018) substantially exceeded the 30-year mean in the number of hours of sunshine, requiring correction of the data. No significantly clear trend with respect to the latitude was observed in the data.

The data are being made available to a wide user base through an online tool. In the wake of this project, it is also being discussed how the measured data can be exploited during case management of occupational disease No (BK) 5103.

This project is closely linked to IFA Project 4227.

Last Update: