🌿 Calcium oxide in workplace air — inhalable and respirable fractions, flame atomic absorption spectrometry (FAAS), PN-Z-04442

Environment PN-Z-04442

Overview

WHAT THE STANDARD COVERS. Scope from the PKN card of the 2023-05 edition, in full (our translation): "This standard gives a method for determining calcium oxide (CAS No. 1305-78-8) in workplace air using flame atomic absorption spectrometry. The method is used when checking sanitary and hygienic conditions. The method is not used in the presence of other calcium compounds in the air examined. The lowest concentration of calcium oxide that can be determined under the sampling and determination conditions described in the standard is 0.097 mg/m3 (for an air sample of 720 l)". We did not have the text of the standard; the card gives neither the sampling method, nor the digestion, wavelength or formulae.

WHAT CHANGED COMPARED WITH THE 2013 EDITION — ACCORDING TO THE TWO CARDS. The scope of the withdrawn 2013-10 edition said the same about the subject and the use, but (1) it ended the sentence on other calcium compounds with a reason: their presence "causes the result of the determination to be overestimated", and (2) it gave a lowest determinable concentration of 0.12 mg/m³ for an air volume of 720 l. In the 2023-05 edition this limit is 0.097 mg/m³ for the same volume. The cards show no other differences.

STATUS (state of the cards on 29 September 2026). The card of PN-Z-04442:2023-05 (Polish version) has no "Withdrawn" header — the standard is CURRENT: published 31-05-2023, 10 pages, price group E, Health, Environment and Medicine Sector, KT 159 for Chemical and Dust Hazards in the Working Environment, ICS 13.040.30, "Replaces: PN-Z-04442:2013-10 - Polish version"; a national standard without an "Introduces" field. The card of PN-Z-04442:2013-10: "Withdrawn and replaced by PN-Z-04442:2023-05 - Polish version", published 07-10-2013, "Withdrawal date: 31-05-2023", 8 pages, "Replaces: PN-Z-04157-03:1990 - Polish version". The title of the 2013 edition and of the 2023 edition differ only in the grammatical form of the Polish word for "flame".

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation-scope database, data loaded up to 17 September 2026, read on 29 September 2026). All notations of the number 04442: 12 entries at 12 laboratories. The 2023-05 edition written as "PN-Z-04442:2023-05" — AB 418, AB 481, AB 632, AB 647, AB 719, AB 849, AB 875, AB 882 and AB 1144; AB 940 writes "PN-Z-04442-10:2023-05" and AB 1642 writes "PN-Z-04442:2023-10" (both forms stand the same way in the current PCA documents; the card knows no 2023-10 edition). The withdrawn 2013-10 edition is cited by AB 1257. The "Laboratories" tab searches for notations BEGINNING WITH "PN-Z-04442" and shows all 12 laboratories — checked with the tab query on the labcoda.pl production server on 29 September 2026: 12. Current scopes on the PCA website (read on 29 September 2026, issues from 26.11.2025 to 17.09.2026): all entries stand in the valid issues, every pair of range limits from the copy appears in the current document, and no entry is suspended.

SUBJECT, TECHNIQUE AND RANGES. All 12 laboratories test workplace air samples (usually "collected on filters") and each gives both fractions — inhalable and respirable. Technique: flame atomic absorption spectrometry (FAAS) — 11 laboratories; AB 719 determines calcium oxide by ICP-OES according to procedure PA-29 (issue 18 of 30.01.2026, excluding its point 3.6) and cites only "point 7" of this standard. Ranges in mg/m³: lower limits from 0.01 (AB 481, AB 940) via 0.02 (AB 849; AB 882 — respirable fraction), 0.025 (AB 1257), 0.03 (AB 882 — inhalable fraction), 0.04 (AB 875), 0.0460 (AB 1144 — inhalable fraction; respirable 0.0490), 0.05 (AB 418) and 0.071 (AB 632) to 0.1 and 0.10 (AB 647, AB 1642 — inhalable fraction; respirable 0.091 and 0.09); upper limits from 8.74 (AB 940) to 119.7 mg/m³ (AB 647, inhalable fraction). AB 719 gives only the mass in the sample: (0.00010 – 10.0) mg for the inhalable and (0.00010 – 5.00) mg for the respirable fraction. The limit on the card (0.097 mg/m³) applies to a 720 l sample; the result in mg/m³ is the mass in the sample divided by the volume of air sampled, so the lower range limits in mg/m³ can only be compared together with the sample volume the laboratory uses.

LIMIT VALUES. The list of maximum admissible concentrations as amended by the regulation of 26 March 2026 (Journal of Laws 2026 item 447, annex, item 528 "Calcium oxide [1305-78-8]"): inhalable fraction — NDS (8-hour value) 2 mg/m³ and NDSCh (short-term value) 6 mg/m³; respirable fraction — NDS 1 mg/m³ and NDSCh 4 mg/m³. In the PDF the table row runs across the page footer, so we read the values from the position of the numbers in columns 3 (NDS) and 5 (NDSCh), checked against the neighbouring row. § 2 of the amending regulation, with the transitional dates, does not mention calcium oxide.

ALONGSIDE THIS STANDARD. In the same entries: AB 632 — instruction IB-13 (issue 7 of 01.10.2023), AB 719 — procedure PA-29. Calcium oxide in workplace air without this standard (7 laboratories): ICP-OES — AB 1302 (PB-61 issue 1 of 03.03.2025), AB 213 (EFO/PB/45/E of 22.10.2025), AB 300 (ISO 15202-3:2004) and AB 869 (OSHA method ID-125G of September 2002, CaO alongside CaCO3 and Ca(OH)2); emission spectrometry with microwave plasma excitation — AB 802 (PB-06/08 issue 3 of 06.01.2025) and AB 934 ("test procedures"); ICP-MS — AB 313 (ISO 15202-2:2020-05, ISO 30011:2010 and PB-SP-01 version 03 of 03.02.2025). All these rows stand in the current PCA scopes without suspension (read on 29 September 2026). Other calcium compounds have their own standards, cited by the same laboratories: calcium hydroxide — PN-Z-04497:2018-09 (8 of the 12 laboratories of this standard: AB 418, AB 481, AB 632, AB 647, AB 719, AB 849, AB 882, AB 1257), calcium carbonate — PN-Z-04294:2001 (9 of 12: AB 418, AB 632, AB 647, AB 719, AB 849, AB 882, AB 1144, AB 1257, AB 1642).

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. The method determines calcium and converts the result to calcium oxide — the card of the 2013 edition says outright that other calcium compounds in the air overestimate the result, and both cards exclude the method when they are present. With dusts in which other calcium compounds occur alongside the oxide, the figure for "calcium oxide" from this standard may therefore contain calcium from those compounds and still look like a correct result. AB 940 gives in the same entry, next to the oxide, also calcium carbonate (0.02 – 15.60) mg/m³ and calcium hydroxide (0.013 – 11.55) mg/m³ "from calculation" — the scope does not say how they are separated.

WHAT WE DO NOT GIVE. We did not have the text of the standard — PKN sells it (10 pages). We do not give the sampling method (filter type, air flow), the digestion, the analytical line, the flame gases, the handling of interferences, formulae or precision; nor do we know what "point 7", cited separately by AB 719, covers.

Method principle

According to the PKN card, calcium oxide in workplace air is determined by flame atomic absorption spectrometry, and the lowest determinable concentration is 0.097 mg/m³ for a 720 l air sample (0.12 mg/m³ in the 2013 edition). The technique measures calcium, which is why the method is not used in the presence of other calcium compounds. We DO NOT GIVE the sampling, digestion and measurement conditions — we did not have the text of the standard.

Applications

• Measurements of exposure to calcium oxide at workplaces — inhalable and respirable fraction, in the scopes of 12 laboratories
• Comparison with NDS 2 mg/m³ (inhalable fraction) and 1 mg/m³ (respirable fraction) and NDSCh 6 and 4 mg/m³ (Journal of Laws 2026 item 447)
• According to the card — checking sanitary and hygienic conditions; not in air containing other calcium compounds

Key parameters

Standard

Standard number

PN-Z-04442:2023-05 (wersja polska)

Title (PL)

Ochrona czystości powietrza — Oznaczanie tlenku wapnia na stanowiskach pracy metodą płomieniowej absorpcyjnej spektrometrii atomowej

Title (EN)

Air purity protection — Determination of calcium oxide at workplaces by flame atomic absorption spectrometry

Step-by-step procedure

1. Status of the document

   PKN card: PN-Z-04442:2023-05 current, replaced the 2013-10 edition (state of the cards on 29 September 2026).

2. Checking that the method applies

   According to the card the method is not used when other calcium compounds (hydroxide, carbonate) are present in the air; they have their own standards, PN-Z-04497 and PN-Z-04294.

3. Air sampling

   Inhalable or respirable fraction onto a filter; we DO NOT GIVE the volume or flow — the card relates the limit of quantification to a 720 l sample.

4. Determination

   Flame atomic absorption spectrometry; we DO NOT GIVE the preparation of the solution or the measurement conditions.

5. Result

   Calcium oxide concentration in mg/m³ (mass in the sample divided by the air volume) and comparison with NDS 2 mg/m³ (inhalable) or 1 mg/m³ (respirable).

Required equipment and apparatus

Health and safety (OHS)

• Calcium oxide reacts with water releasing heat and is irritant — when sampling in dusty conditions, protect the eyes and the respiratory tract
• SUBSTANTIVE NOTE: the technique measures calcium; in the presence of calcium hydroxide or carbonate the "calcium oxide" result by this standard is overestimated — as the card of the 2013 edition says

Frequently asked questions