Germany: Occupational Health Regulations
Regulatory Authorities
Occupational health and safety (OHS) standards in Germany are based on the federal “Chemicals Act” (gesetzliche Grundlage “Chemikaliengesetz”) and on a federal government rule, which addresses various issues related to dangerous substances (“Gefahrstoffverordnung”).
Exposure limits in the workplace are usually proposed by a special scientific board of DFG (Deutsche Forschungsgemeinschaft). Next, the proposed limits are discussed with all stakeholders within the MAK-Kommission. The final limits are established by the German Ministry of Labor (Bundesministerium für Arbeit - BMA) through TRGS regulations (technische Regeln für Gefahrstoffe). The TRGS documents are published in the “Bundesarbeitsblatt”.
The occupational health and safety standards are enforced by occupational insurance organizations called Berufsgenossenschaften. There are 35 Berufsgenossenschaften for different areas in the industry (e.g. Tiefbauberufsgenossenschaft—TBG responsible for construction). These insurance organizations perform various functions, such as air quality measurements at the site, to ensure compliance with the regulations.
All Berufsgenossenschaften have a common institution BIA (Berufsgenossenschaftliches Institut für Arbeitssicherheit) which performs many functions, including regular publication of all OHS limits and rules.
The above organization extends to all occupational health environments with the exception of coal mining. Until the year 2002 the OHS matters in the coal mining are the responsibility of state (Land) mining authorities called Oberbergbehörde.
Exposure Limits
There are two types of exposure limits:
- MAK (Maximale Arbeitsplatzkonzentration) is the maximum concentration of a substance in the ambient air in the workplace which has no adverse effect on the workers' health.
- TRK (Technische Richtkonzentration) is the concentration of a substance in the ambient air in the workplace that can be achieved using technically available measures.
Once established, both types of limits are legally binding and have to be observed in the workplace. Table 1 summarizes the TRK exposure limits for the major diesel exhaust pollutants [5694].
| Substance | ppmv | mg/m3 | Category* |
|---|---|---|---|
| CO | 30 | 35 | 2 |
| CO2 | 5000 | 9100 | 2 |
| NO | 2 | 2.5 | 2 |
| NO2 | 0.5 | 0.95 | 2 |
| HCHO | 0.3 | 0.37 | 2 |
| SO2 | 1 | 2.7 | 1 |
| Diesel particulates (EC) | - | 0.05a | - |
|
* All values in the table have to be met as work-shift time weighted averages. The following short term exposure categories apply: 1 - ceiling value, not to be exceeded at any point in time; 2 - ceiling value = 2 × the limit value | |||
The diesel particulate emissions (DME - Dieselmotorenemissionen) are defined as elemental carbon (EC) and are limited in size to about 5 µm (EN 481). This definition is different, and more precise, than the dilution tunnel particulate matter determination, which is used for the tailpipe engine emission measurement. Contrary to the CVS dilution tunnel sampling, the German occupational health definition excludes such artifacts as water, sulfuric acid, or hydrocarbons. These substances produce condensates under the artificial conditions in the dilution tunnel. German authorities concluded that the condensates should not be included in the measured particulate mass, due to the different health impact of condensates and insoluble carbon particles. The gaseous pollutants are regulated separately and measured in the gas phase.
Diesel particulates are classified as “probably carcinogenic for humans”. This classification requires that the “best available technology” (BAT) is used for emission reduction.
Diesel Engine Regulations
Specific rules pertaining to the use of diesel engines in occupational health environments were first introduced on 30 April 1993 (TRGS 554). These regulations introduced a general TRK exposure limit for diesel particulates of 0.2 mg/m3 and a limit of 0.6 mg/m3 for underground non-coal mines and tunneling. The particulates were defined as total carbon (EC + OC) and determined by a coulometric analysis.
The regulation was modified several times. In 1996, the TRK limits for diesel particulates in the workplace and in mining/tunneling were lowered to 0.1 and 0.3 mg/m3, respectively. In 2017, the TRK limit for diesel particulates was further lowered to 0.05 mg/m3. The definition of diesel particulates was changed to elemental carbon (EC). The measurement involves a two stage thermal analysis with coulometric identification [Method 2 according to ZH 1/120.44 /Oct. 1990 (BIA) and VDI standard 2465].
Coal mines are exempted from the above limits due to the difficulties in differentiating between diesel particulates and coal dust.
The TRGS 554 sets several additional requirements that have to be observed whenever diesel engines are operated in buildings, underground, or other enclosed areas. These additional provisions have to be also observed in coal mines. The following are some of the requirements:
- Diesel engines that are entirely or partially operated in enclosed spaces or underground must be equipped with particulate filters, provided such filters are technically feasible.
- The particulate filters must achieve at least 70% total gravimetric filtration rate, as measured on the UBA (Umwelt Bundesamt) engine test cycle.
- Diesel engines must undergo periodic measurements of smoke number and CO level.
It should be emphasized that diesel particulate filters are required in addition to the TRK exposure limit. The filtration efficiency of most filters that are used is better than the required 70%. As a result, according to the measurements of TBG, the average particulate exposure in tunnel sites has been reduced to well below 0.1 mg/m3, a much lower value than the TRK of 0.3 mg/m3.