Alveolar fraction

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Conventional values for the inhalable fraction , thoracic fraction and respirable fraction as a function of the aerodynamic diameter according to DIN EN 481

As a respirable fraction ( respirable fraction ) is 14042 the mass fraction of, inter alia, in the standards EN 481, ISO 7708, EN ISO 10882-1 and EN suspended designated or airborne particles, the way up to the ciliierten penetrates airways. It is a variable for assessing possible health hazards in the workplace and depends, among other things, on the person being considered and their breathing style. By convention, the EN 481 standard specifies that the respirable fraction is determined by calculating the inhalable fraction : "The percentage [...] of the inhalable convention that is to be collected with an aerodynamic diameter D in micrometers results from a cumulative Log-normal distribution with a median value of 4.25 µm and a geometric standard deviation of 1.5. ”For the target group“ sick or weak people or children ”, the ISO 7708 standard defines a median value of 2.5 µm. This definition is also used to define the fine dust category PM 2.5 .

With reference to the DIN EN 481 standard, the various technical rules for hazardous substances ( TRGS ) refer to the respirable fraction as " A dust " or "respirable dust fraction". The term "A dust" is also used - together with the term "A dust fraction" - in the DIN 33897 Part 1 standard as a synonym for "respirable fraction".

However, the EN 481 standard for determining the respirable fraction still allows the use of measuring devices that follow the Johannesburg Convention , as these show approximately 20% higher results.

literature

  • DIN EN 481: 1993-09 workplace atmosphere ; Definition of the particle size distribution for the measurement of airborne particles (German version EN 481: 1993) . Beuth Verlag, Berlin.

Individual evidence

  1. ↑ DIN ISO 7708: 1996-01 Air quality - Determination of particle size distributions for health-related particulate matter sampling (ISO 7708: 1995) . Beuth Verlag, Berlin, p. 3.
  2. ↑ DIN EN ISO 10882 Part 1: 2001-04 Occupational health and safety during welding and allied processes - Sampling of particulate substances and gases in the breathing zone of the welder - Part 1: Sampling of particulate substances (ISO 10882-1: 2011) . Beuth Verlag, Berlin, p. 8.
  3. ↑ DIN EN 14042: 2003-07 Workplace atmosphere - Guidelines for the application and use of procedures and devices for the determination of chemical and biological agents; German version EN 14042: 2003 . Beuth Verlag, Berlin, p. 8.
  4. ↑ DIN EN 481: 1993-09 workplace atmosphere ; Definition of the particle size distribution for the measurement of airborne particles (German version EN 481: 1993) . Beuth Verlag, Berlin. P. 4.
  5. ↑ DIN ISO 7708: 1996-01 Air quality - Determination of particle size distributions for health-related particulate matter sampling (ISO 7708: 1995) . P. 8.
  6. ↑ DIN EN ISO 23210: 2009-12 Emissions from stationary sources - Determination of the mass concentration of PM10 / PM2.5 in exhaust gas - Measurement at low concentrations with impactors (ISO 23210: 2009); German version EN ISO 23210: 2009 . Beuth Verlag, Berlin. P. 6.
  7. ↑ TRGS 900 edition: January 2006, BArBl issue 1/2006 pp. 41–55, last changed and supplemented: GMBl 2015 pp. 139–140 v. March 2, 2015 [No. 7]
  8. ↑ a b TRGS 559 edition: February 2010, Mineralischer Staub (GMBl No. 22/23 of April 9, 2010, p. 459, last amended GMBl No. 29 of September 1, 2011, p. 578)
  9. ↑ DIN 33897-1: 2007-06 Workplace atmosphere - Routine method for determining the dustiness of bulk goods - Part 1: Basics . Beuth Verlag, Berlin, p. 6.
  10. ↑ DIN EN 481: 1993-09 workplace atmosphere ; Definition of the particle size distribution for the measurement of airborne particles (German version EN 481: 1993). Beuth Verlag, Berlin. P. 2.