To measure dusts, the GSA Messgerätebau GmbH offers you a selection of professional indoor air measuring devices for accurate testing at the workplace.
Our various sampling systems for particle measurements of dust fractions such as A-dust and E-dust of the GSA Messgerätebau can help you with this.
We can provide you with the best possible support, particularly in the field of particle measurements of dust fractions such as A-dust and E-dust, as our devices have a wide range of possible applications. We can even offer you various measuring devices such as the measuring device SG5100ex for potentially explosive atmospheres. Please contact us at any time for individual advice.
In order to determine whether certain potential hazards exist, it is important to deal with the topic of occupational limit values (OELs).
The occupational limit value (OEL) describes the highest possible concentration of a substance that is permitted at the workplace. This is based on regular contact over eight hours a day, five days a week. The concentration may only be so high that no effects on health can be detected within a 40-hour week.
As part of the revision of the Hazardous Substances Ordinances on 01.01.2005, the term “occupational limit value” (OEL) replaced the old term “maximum workplace concentration” (MAC).
Definition of occupational limit value (OEL)
TRGS 900 is used for the consideration of the occupational limit value. In addition to the general terminology, the comparative parameters are also defined there. The following formula is used to determine the concentration of the substance:
The following parameters apply to the molar volume:
- Ambient temperature of 20°Celsius
- Pressure of 101.3 kPa
- Volume of 24.1 L
The determined sample concentration is reproduced under real conditions, i.e. the ambient parameters during sampling are included in the calculation. The different potencies must be taken into account in the calculation and adjusted accordingly.
The dust limit value – important for measuring dusts at the workplace
Another specification of the OEL is the dust limit value, which applies to all insoluble dusts. A distinction is made between A-dust and E-dust. For A-dust, a limit value of 1.25 mg/m3 applies, based on an average density of 2.5 g/cm³. This value corresponds to the current regulations, whereby a gradual reduction is possible by 2018. The aim is to permanently reduce exposure at the workplace. You can find more details on this in TRGS 900.
A dust limit value of 10 mg/m³ applies to E-dust.
If the exposure at the workplace is subject to strong fluctuations, a dose-based monitoring concept can be implemented for one month. The average is determined from the shift averages, whereby this may not exceed the value of 3 mg/m³ for A-dust.
However, permanent strain should always be avoided.
Below is a brief overview of some substances to which the occupational limit value applies (list is not exhaustive):
The occupational limit value must not be applied to:
-
- ultrafine dusts
- Dusts with specific toxicity (e.g. mutagenic, carcinogenic, fibrogenic or sensitizing effects)
- soluble substances
- Lacquer aerosols
- Coarsely dispersed particle fractions
- Dusts with manufactured nanomaterials
- underground workplaces.
Sources:
[1] http://www.bfga.de/arbeitsschutz-lexikon-von-a-bis-z/fachbegriffe-j-r/mak-wert-fachbegriff/
[2] http://www.chemie.de/lexikon/Maximale_Arbeitsplatz-Konzentration.html
[3] /GeltendeFassung.wxe?Abfrage=Bundesnormen&Gesetzesnummer=20001418&ShowPrintPreview=True
[4] https://de.wikipedia.org/wiki/Maximale_Arbeitsplatz-Konzentration
[5] http://www.dguv.de/staub-info/rechtsgrundlagen/grenzwerte/asgw/index.jsp
[6] https://www.bgrci.de/fileadmin/BGRCI/Banner_und_Artikelbilder/Veranstaltungen/Der_neue_Allgemeine_Staubgrenzwert_-_Vortrag_von_Karlheinz_Guldner.pdf