🌿 Cobalt and its compounds in workplace air — membrane filter, mineralisation in aqua regia and concentrated nitric(V) acid, solution in dilute nitric(V) acid, flame atomic absorption spectrometry (FAAS); lowest determinable concentration according to the standard 0.01 mg/m³ (as Co), MAC (NDS) 0.02 mg/m³; PN-Z-04291:2003 (withdrawn 11-08-2014)
In short
Polish standard of 2003 with a method for determining cobalt and its compounds in workplace air by flame atomic absorption spectrometry, with a lowest determinable concentration of 0. The test is performed according to PN-Z-04291:2003; Ranges in accreditation scopes (PN-Z-04291): from 0.0014 mg/m³ (AB 481, AB 1642) to 0.69 mg/m³ (AB 418); AB 719 — 0.00050–1.00 mg per sample (ICP-OES). The procedure comprises 4 steps; it is used for: Workplace air — cobalt and its inorganic compounds as Co — in the current scopes of 8 laboratories, despite the withdrawal of the standard, Assessment of occupational exposure against the NDS of 0.02 mg/m³ (Journal of Laws 2026 item 447, item 328 of the list), For comparison: the current PN-Z-04454:2014-08 (graphite furnace) — in the scopes of 2 laboratories.
At a glance
- Standard: PN-Z-04291:2003
- Category: Environment
- Procedure steps: 4
- STATUS (cards as of 04.10.2026): PN-Z-04291:2003 WITHDRAWN — withdrawal date 11-08-2014; current for cobalt: PN-Z-04454:2014-08 (published 01-08-2014; card without a "Replaces" field)
- Edition (from the PKN card): PN-Z-04291:2003, Polish version; published 28-10-2003, 4 pages, KT 159 Chemical and Dust Hazards in the Working Environment, ICS 13.040.30; replaced PN-Z-04161-01:1986 and PN-Z-04161-02:1986
- Lowest determinable concentration (cards): PN-Z-04291:2003 — 0.01 mg/m³ (as Co); PN-Z-04454:2014-08 — about 0.002 mg/m³ for 720 l of air
Overview
WHAT THE STANDARD COVERS. Scope from the PKN catalogue card, in full (our translation): "A method is described consisting in passing a known amount of air through a membrane filter in order to deposit cobalt and its compounds on it, mineralising the sample in aqua regia and in concentrated nitric(V) acid and preparing the solution for analysis in dilute nitric(V) acid. Cobalt and its compounds in the solution obtained are determined by flame atomic absorption spectrometry. The lowest concentration of cobalt and its compounds (as cobalt) that can be determined by this method is 0.01 mg/m3". We did not have the text of the standard (4 pages).
NDS VALUE (list in the annex to the regulation of 26 March 2026, Journal of Laws 2026 item 447). Item 328: "Cobalt [7440-48-4] and its inorganic compounds – as Co" — NDS 0.02 mg/m³, no NDSCh and no separate value for the respirable fraction. The lowest determinable concentration according to the card of this standard, 0.01 mg/m³, is 50 % of the NDS.
STATUS (cards as of 04.10.2026). The card of PN-Z-04291:2003 (Polish version) has the heading "Withdrawn": published 28-10-2003, withdrawal date 11-08-2014, 4 pages, price group B, Health, Environment and Medicine Sector, KT 159 Chemical and Dust Hazards in the Working Environment, ICS 13.040.30, "Replaces PN-Z-04161-01:1986, PN-Z-04161-02:1986"; the card does not indicate a replacing standard. The PKN search (queries "PN-Z-04454" and "kobaltu" (cobalt), 04.10.2026) shows for cobalt the CURRENT standard PN-Z-04454:2014-08 "Air purity protection — Determination of cobalt and its compounds at workplaces by graphite furnace atomic absorption spectrometry" — its card: published 01-08-2014, 8 pages, KT 159; scope: graphite furnace atomic absorption spectrometry, lowest determinable concentration "about 0.002 mg/m3 (for an air volume of 720 l)". The dates are consistent with succession (PN-Z-04454 published 01-08-2014, PN-Z-04291 withdrawn 11-08-2014), but the card of PN-Z-04454 has no "Replaces" field.
WHAT CIOP SAYS (P. Wasilewski, "Cobalt and its compounds. Method for determination in workplace air", Podstawy i Metody Oceny Środowiska Pracy 2022, no. 1(111), pp. 133–145 — introduction and experimental part read). "Currently the standard PN-Z-04454:2014 … (ET-AAS) is in force in Poland. In this standard the limit of quantification of cobalt is 0.002 mg/m3"; according to the article the standard needs amending, because the Interdepartmental Commission for MAC and MAI proposed lowering the NDS for the respirable fraction to 0.001 mg/m³. The article describes a new ET-AAS method for the respirable fraction (0.0001–0.002 mg/m³, sampler with an impactor 8 l/min, 37 mm MCE filter, mineralisation with nitric(V) and hydrochloric acid, 242.5 nm, LOQ 0.017 µg/m³, expanded uncertainty 23.56 %); according to the article the main hazard are soluble cobalt salts, classified as carcinogenic category 1A. In the list of 26.03.2026 the NDS for cobalt is 0.02 mg/m³, with no separate respirable value — the proposed value of 0.001 mg/m³ is not in it.
HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database, data load up to 17.09.2026, read on 04.10.2026). The number 04291 appears in 8 records at 8 laboratories; in the current PCA documents (read on 03.10.2026; issues from 08.01.2026 to 18.08.2026 — all issued after the withdrawal of the standard) — in 8 rows at the same laboratories; a search of all PCA documents downloaded from the BIP found no laboratories outside the database copy; no item is suspended and no document repeats pages. Form "PN-Z-04291:2003" — 7 laboratories; AB 719 — "PN-Z-04291:2003 pkt 7" (clause 7) next to procedure PA-29 edition 18 of 30.01.2026 "excluding clause 3.6". The "Laboratories" tab (query "PN-Z-04291") shows all 8 laboratories — checked with the tab's query on the production server labcoda.pl on 04.10.2026. The current PN-Z-04454 is cited in the database copy by 2 laboratories: AB 849 ("PN-Z-04454:2014", ETAAS, 0.0006–0.056 mg/m³) and AB 632 ("PN-Z-04454:2014-08" next to instruction IB-09 edition 1 of 01.08.2023, ETAAS, inhalable fraction, 0.00138–0.0417 mg/m³).
WHAT THE LABORATORIES WITH PN-Z-04291 TEST (database copy). Object: working environment — air, air samples collected on filters. Quantity: concentration (content) of cobalt and its inorganic compounds as Co. Ranges in mg/m³: 0.0014–0.069 (AB 1642), 0.0014–0.14 (AB 481), 0.00150–0.070 (AB 1144), 0.0018–0.69 (AB 418), 0.002–0.042 (AB 484), 0.002–0.4 (AB 647), 0.0069–0.069 (AB 340); AB 719 — 0.00050–1.00 mg per sample. Technique: flame atomic absorption spectrometry (FAAS) — 7 laboratories; AB 719 — inductively coupled plasma optical emission spectrometry (ICP-OES).
WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. First — sensitivity relative to the NDS: according to the card the lowest concentration determinable by this method is 0.01 mg/m³, i.e. half of the NDS (0.02 mg/m³); all seven laboratories with a range in mg/m³ state a lower bottom limit (from 0.0014 to 0.0069 mg/m³), which requires conditions different from those in the standard — the report should name them. Second — status: the standard has been withdrawn since 11-08-2014, and since 01-08-2014 the catalogue has contained PN-Z-04454 with a graphite furnace (about 0.002 mg/m³); 8 laboratories have the withdrawn standard in their scope, 2 — the current one. Third — technique: AB 719 determines cobalt by ICP-OES and cites only clause 7 of the standard. Fourth — fraction: the list does not distinguish fractions for cobalt; the 2022 CIOP article describes a method for the respirable fraction for the proposed, not introduced value of 0.001 mg/m³.
WHAT WE DO NOT GIVE. We did not have the text of PN-Z-04291:2003 or of PN-Z-04454:2014-08 — we do not give the volume or flow rate of air sampling, the type of filter, mineralisation conditions, wavelength, measurement conditions or calculations of either of them. We do not attribute the figures from the 2022 CIOP article to any standard.
Method principle
A known amount of workplace air is passed through a membrane filter on which cobalt and its compounds are deposited. The sample is mineralised in aqua regia and concentrated nitric(V) acid, the solution for analysis is prepared in dilute nitric(V) acid and cobalt is determined by flame atomic absorption spectrometry; the result as Co is compared with the NDS of 0.02 mg/m³. Lowest determinable concentration according to the card — 0.01 mg/m³. The standard is withdrawn (11-08-2014); WE DO NOT GIVE details — we did not have the text of the standard.
Applications
- Workplace air — cobalt and its inorganic compounds as Co — in the current scopes of 8 laboratories, despite the withdrawal of the standard
- Assessment of occupational exposure against the NDS of 0.02 mg/m³ (Journal of Laws 2026 item 447, item 328 of the list)
- For comparison: the current PN-Z-04454:2014-08 (graphite furnace) — in the scopes of 2 laboratories
Key parameters
| Parameter | Value |
|---|---|
| STATUS (cards as of 04.10.2026) | PN-Z-04291:2003 WITHDRAWN — withdrawal date 11-08-2014; current for cobalt: PN-Z-04454:2014-08 (published 01-08-2014; card without a "Replaces" field) |
| Edition (from the PKN card) | PN-Z-04291:2003, Polish version; published 28-10-2003, 4 pages, KT 159 Chemical and Dust Hazards in the Working Environment, ICS 13.040.30; replaced PN-Z-04161-01:1986 and PN-Z-04161-02:1986 |
| Lowest determinable concentration (cards) | PN-Z-04291:2003 — 0.01 mg/m³ (as Co); PN-Z-04454:2014-08 — about 0.002 mg/m³ for 720 l of air |
| NDS (Journal of Laws 2026 item 447, item 328) | cobalt and its inorganic compounds, as Co — 0.02 mg/m³; no NDSCh |
| Ranges in accreditation scopes (PN-Z-04291) | from 0.0014 mg/m³ (AB 481, AB 1642) to 0.69 mg/m³ (AB 418); AB 719 — 0.00050–1.00 mg per sample (ICP-OES) |
| Coverage in accreditation scopes (read 04.10.2026) | PN-Z-04291 — 8 laboratories, 8 records, 8 rows in PCA; "Laboratories" tab ("PN-Z-04291") — 8, the same on the production server; PN-Z-04454 — 2 laboratories (AB 632, AB 849) |
Standard
- Standard number
- PN-Z-04291:2003
- Title (PL)
- Ochrona czystości powietrza — Oznaczanie kobaltu i jego związków na stanowiskach pracy metodą płomieniową absorpcyjnej spektrometrii atomowej
- Title (EN)
- Air purity protection — Determination of cobalt and its compounds at workplaces by flame atomic absorption spectrometry
Step-by-step procedure
-
Status
PN-Z-04291:2003 withdrawn 11-08-2014; current for cobalt PN-Z-04454:2014-08 (cards as of 04.10.2026).
-
Sampling
Known amount of air through a membrane filter; WE DO NOT GIVE details.
-
Mineralisation
Aqua regia and concentrated nitric(V) acid; solution in dilute nitric(V) acid.
-
Measurement, result and assessment
FAAS; concentration as Co compared with the NDS of 0.02 mg/m³ (Journal of Laws 2026 item 447); lowest determinable concentration 0.01 mg/m³ — half of the NDS.
Required equipment and apparatus
| Equipment | Example | Indicative price |
|---|---|---|
| Flame atomic absorption spectrometer | Determination of cobalt in the solution (PKN card); WE DO NOT GIVE measurement parameters | — |
| Air sampling set with a membrane filter | Deposition of cobalt and its compounds (PKN card); WE DO NOT GIVE the volume | — |
Reagents, media and consumables
| Reagent | CAS | Details |
|---|---|---|
| Aqua regia and concentrated nitric(V) acid | — | For mineralising the sample (PKN card) |
| Dilute nitric(V) acid | — | For preparing the solution for analysis (PKN card) |
Health and safety (OHS)
- Work with aqua regia and concentrated nitric(V) acid — in a fume hood, chemical laboratory safety rules
- TECHNICAL NOTE: standard withdrawn on 11-08-2014; the lowest determinable concentration according to the card is half of the NDS — a bottom limit below 0.01 mg/m³ requires conditions different from those in the standard
Frequently asked questions
Which standard describes this test?
The test is performed according to PN-Z-04291:2003 — “Air purity protection — Determination of cobalt and its compounds at workplaces by flame atomic absorption spectrometry”.
How does this method work?
A known amount of workplace air is passed through a membrane filter on which cobalt and its compounds are deposited. The sample is mineralised in aqua regia and concentrated nitric(V) acid, the solution for analysis is prepared in dilute nitric(V) acid and cobalt is determined by flame atomic absorption spectrometry; the result as Co is compared with the NDS of 0.
What is the measuring range and accuracy?
STATUS (cards as of 04.10.2026): PN-Z-04291:2003 WITHDRAWN — withdrawal date 11-08-2014; current for cobalt: PN-Z-04454:2014-08 (published 01-08-2014; card without a "Replaces" field); Edition (from the PKN card): PN-Z-04291:2003, Polish version; published 28-10-2003, 4 pages, KT 159 Chemical and Dust Hazards in the Working Environment, ICS 13.040.30; replaced PN-Z-04161-01:1986 and PN-Z-04161-02:1986; Lowest determinable concentration (cards): PN-Z-04291:2003 — 0.01 mg/m³ (as Co); PN-Z-04454:2014-08 — about 0.002 mg/m³ for 720 l of air; NDS (Journal of Laws 2026 item 447, item 328): cobalt and its inorganic compounds, as Co — 0.02 mg/m³; no NDSCh.
How long does the test take?
The procedure comprises 4 steps. The standard does not give a duration for every stage — the laboratory's own procedure decides.
What equipment is required?
Flame atomic absorption spectrometer, Air sampling set with a membrane filter.
Where is this test used?
Workplace air — cobalt and its inorganic compounds as Co — in the current scopes of 8 laboratories, despite the withdrawal of the standard; Assessment of occupational exposure against the NDS of 0.02 mg/m³ (Journal of Laws 2026 item 447, item 328 of the list); For comparison: the current PN-Z-04454:2014-08 (graphite furnace) — in the scopes of 2 laboratories.
What safety precautions apply?
Work with aqua regia and concentrated nitric(V) acid — in a fume hood, chemical laboratory safety rules; TECHNICAL NOTE: standard withdrawn on 11-08-2014; the lowest determinable concentration according to the card is half of the NDS — a bottom limit below 0.01 mg/m³ requires conditions different from those in the standard.
Which laboratory can perform this test?
The test is performed by laboratories accredited to ISO/IEC 17025. On LabCoda you can find them by the standard number PN-Z-04291.