Proficiency testing for inorganic acids

(HCl, HNO3 and H2SO4, H3PO4)

Test gas stream

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IFA's test gas stream
Source: IFA

Proficiency testing (PT) is offered either with or without own sampling. The participants can choose between carrying out the sampling of volatile inorganic acids themselves or receiving samples ready for analysis. For HCI and HNO3, the IFA recommends that the analysis method for hazardous substances described in DFG [1], NIOSH [2] resp. IFA Folder No. 6172 [3] be employed as the procedure. For H2SO4 and H3PO4 preparation is suggested according to the IFA folder, identification number 6173 sheet 1 and 2 [4], DFG [5] resp. NIOSH [6]. The analysis should be conducted using ion chromatography.

1 Proficiency testing with sampling

1.1. Volatile inorganic acids

A large dynamic test gas stream was erected at the IFA. The test gas stream allows for parallel sampling for up to 11 participants.

  • When: 20/21 March 2018 (Minimum number of participants: 8)
  • Where:
    Institut für Arbeitsschutz der Deutschen Gesetzlichen Unfallversicherung (IFA)
    Alte Heerstr. 111
    53757 Sankt Augustin
  • Concentration range: 1/10 to two times the AGW1 value
  • Number of test series: 3
  • Duration: 2 test series of 2 hours each, 1 test series of 15 minutes, plus preparation time and run-in period.
  • Solvent selection: HCI, HNO3
  • Sampling: Active sampling
  • Accomodations: Hotels at Sankt Augustin

Please note that for each test series only 4 l/min test gas is available for each participant.

Participants will receive detailed information on the PT scheme, a description of the apparatus, and the connections for the sampling devices in particular, in good time.

1.2 Non-volatile inorganic acids (see below)

Each participant receives an additional sample set for H2SO4 and H3PO4.

2 Proficiency testing without sampling

2.1 Volatile inorganic acids

The loading of sample carriers is conducted at the dynamic test gas stream of the IFA. Alkaline impregnated quartz fibre filters are used as sampling carriers.

Each participant receives a sample set consisting of:

  • three loaded sample carriers and
  • two unloaded sample carriers for blank value adjustment.

2.2 Non-volatile inorganic acids

Quartz fibre filters doped with sulphuric and phosphoric acids will be offered as in the preceding years.

The samples will be prepared by means of piezoelectric microdispensing. This includes

  • three loaded filters which are stabilised directly after loading and
  • two unloaded stabilised filters.

1 The German acronym AGW stands for Arbeitsplatzgrenzwert (Occupational Exposure Limit value – OEL). For carcinogenic substances and substances without AGW the database GESTIS – International limit values for chemical agents ( is used.


[1] Deutsche Forschungsgemeinschaft (DFG). Volatile inorganic acids. In: Analyses of hazardous substances in air. Vol. 6. Ed.: A. Kettrup. Wiley-VCH, Weinheim 1998

[2] Volatile Acids by Ion Chromatography (HCl, HBr, HNO3), Method 7907. In: NIOSH, Manual of Analytical Methods, Fifth Edition, Issue 1, 20 May 2014

[3] Anorganische Säuren, flüchtig: Bromwasserstoff, Chlorwasserstoff, Salpetersäure (Kennzahl 6172). In: IFA-Arbeitsmappe Messung von Gefahrstoffen. 38. Lfg. IV/2007. Ed.: Institut für Arbeitsschutz der DGUV (IFA), Sankt Augustin. Erich Schmidt, Berlin 1989 - Loose-leaf edition

[4] Anorganische Säuren, partikulär: Phosphorsäure, Schwefelsäure (Kennzahl 6173). In: IFA-Arbeitsmappe Messung von Gefahrstoffen. 46. Lfg. XII/2010.

[5] Deutsche Forschungsgemeinschaft (DFG). Inorganic acid mists (H2SO4, H3PO4). In: Analyses of hazardous substances in air. Vol. 6. Ed.: A. Kettrup. Wiley-VCH, Weinheim 2002

[6] Non-Volatile Acids (H2SO4, H3PO4). Method 7908. In: NIOSH, Manual of Analytical Methods, Fifth Edition, Issue 1, 20 May 2014


Division 2: Chemical and biological hazards

Brigitte Maybaum
Krista Gusbeth
Franziska Nürnberger