🌿 Hydrogen cyanide in air — a 1970 standard whose PKN card has no "Scope" field (the method cannot be determined from the card); in accreditation scopes a spectrophotometric or potentiometric method; MAC (NDS) for hydrogen cyanide and cyanides (as CN) 1 mg/m³, ceiling value (NDSP) 5 mg/m³, "skin" notation; PN-Z-04053:1970 (withdrawn 10-04-2006)

Environment PN-Z-04053

Overview

WHAT THE STANDARD COVERS. The PKN card of PN-Z-04053:1970 has no "Scope" field — the only information about its content is the title "Determination of hydrogen cyanide content in air" (our translation). We did not have the text of the standard (3 pages), so we do not know which method it describes: neither the sampling, nor the measurement technique, nor the determinability. The CIOP index of methods from 2000–2017 has no entry for hydrogen cyanide or cyanides.

NDS VALUES (list in the annex to the regulation of 26 March 2026, Journal of Laws 2026 item 447, item 126). "Hydrogen cyanide and cyanides – as CN", "skin" notation: hydrogen cyanide [74-90-8] — NDS 1 mg/m³ (0.9 ppm), NDSP 5 mg/m³ (4.5 ppm), no NDSCh; sodium cyanide [143-33-9] and potassium cyanide [151-50-8] — NDS 1 mg/m³, NDSP 5 mg/m³, inhalable fraction.

STATUS (card as of 04.10.2026). The card of PN-Z-04053:1970 (Polish version) has the heading "Withdrawn": published 22-04-1970, withdrawal date 10-04-2006, 3 pages, price group B, Health, Environment and Medicine Sector, KT 159 Chemical and Dust Hazards in the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-04053:1958"; the card does not name a replacing standard. The PKN search for "PN-Z-04053" shows two items, both "Withdrawn": the 1970 edition and "Rapid method for determining hydrogen cyanide content in air" of 1958. Under "cyjanowodoru" all 8 items are labelled "Withdrawn" — none of them is a current standard for hydrogen cyanide in air.

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 04053 appears in 6 records at 4 laboratories; in the current PCA documents (read on 03.10.2026; issues from 16.04.2026 to 23.07.2026 — all issued 20 years after the withdrawal of the standard) — in 6 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. All laboratories write "PN-70/Z-04053"; AB 719 in one item "z wyłączeniem pkt. 2.4", AB 1004 in one "z wyłączeniem pkt. 7". The "Laboratories" tab: "PN-70/Z-04053" shows 4 laboratories, the same in the copy and on the labcoda.pl production server (tab query of 04.10.2026).

WHAT THE LABORATORIES TEST (database copy and PCA documents). Spectrophotometric method: AB 647 — working environment, air samples collected into an absorbing solution, hydrogen cyanide 0.075–5 mg/m³ (0.066–4.5 ppm; 0.3–20.0 µg per sample); AB 719 — two items, content of hydrogen cyanide 0.00030–0.0240 mg per sample: working environment (samples on filters, prepared filters, sorption tubes prepared with silica gel or in scrubbers; "as CN") and general environment — waste gases ("excluding point 2.4"); AB 882 — working environment, hydrogen cyanide and cyanides as CN, 0.09–10.4 mg/m³ (0.080–9.24 ppm; 0.0006–0.063 mg per sample), together with procedure PB-09 edition 2 of 01.08.2023. Potentiometric method: AB 1004 — hydrogen cyanide and cyanides as CN⁻, together with instruction ILR 16 edition 1 of 01.03.2021: working environment, samples collected into an absorbing solution, 0.1–20 mg/m³ (0.09–17.8 ppm; 0.0005–0.1 mg per sample), and waste gases, 0.02–33.33 mg/m³ ("excluding point 7").

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. First — unknown method of the standard: the card has no scope, and the laboratories apply two different techniques (spectrophotometry and potentiometry) and different sampling methods under the same number; the record "PN-70/Z-04053" does not show which method was used for the determination. Second — what is measured: the NDS concerns "hydrogen cyanide and cyanides – as CN", while AB 647 gives hydrogen cyanide alone, AB 882 and AB 1004 hydrogen cyanide and cyanides; a result for hydrogen cyanide alone does not cover cyanides in the inhalable fraction. Third — units: AB 719 gives its range only in mg per sample (0.00030–0.0240 mg), without mg/m³ — comparison with the NDS of 1 mg/m³ depends on the volume of air sampled, which the accreditation scope does not give. Fourth — status: the standard has been withdrawn since 2006, with no current successor in the PKN catalogue, and 4 laboratories have it in scopes issued in 2026. Fifth — object: AB 719 and AB 1004 also apply the standard to waste gases, for which the NDS is not a reference value, excluding points of the standard whose content we do not know. Sixth — "skin" notation: a measurement in air does not cover absorption through the skin.

WHAT WE DO NOT GIVE. We did not have the text of the standard, and the card has no scope — we do not give the method of the standard, the reagents, the sampling, the determinability or calculations; we do not assess which of the techniques used by the laboratories corresponds to the standard. We do not claim that another standard has replaced PN-Z-04053:1970 — PKN names none.

Method principle

The PKN card of PN-Z-04053:1970 "Determination of hydrogen cyanide content in air" has no "Scope" field, so WE DO NOT GIVE the principle of the method — we did not have the text of the standard. In current accreditation scopes the laboratories citing this standard use a spectrophotometric method (AB 647, AB 719, AB 882) or a potentiometric one (AB 1004). The standard is withdrawn (10-04-2006) and has no named successor.

Applications

• Workplace air — hydrogen cyanide, and hydrogen cyanide and cyanides as CN (AB 647, AB 719, AB 882, AB 1004); waste gases (AB 719, AB 1004); despite the withdrawal of the standard
• Assessment of occupational exposure against the NDS of 1 mg/m³ and the NDSP of 5 mg/m³ for hydrogen cyanide and cyanides as CN, "skin" notation (Journal of Laws 2026 item 447, item 126)

Key parameters

Standard

Standard number

PN-Z-04053:1970

Title (PL)

Oznaczanie zawartości cyjanowodoru w powietrzu

Title (EN)

Determination of hydrogen cyanide content in air

Step-by-step procedure

1. Status

   PN-Z-04053:1970 withdrawn 10-04-2006, with no successor named (card as of 04.10.2026).

2. Sampling

   WE DO NOT GIVE the method of the standard; laboratories sample into an absorbing solution, into scrubbers, onto filters or tubes (accreditation scopes).

3. Measurement

   WE DO NOT GIVE the technique of the standard; in accreditation scopes spectrophotometry or potentiometry.

4. Result and assessment

   Result as CN against the NDS of 1 mg/m³ and the NDSP of 5 mg/m³; "skin" notation — a measurement in air does not cover the dermal route.

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• Hydrogen cyanide and cyanides — standards and samples in a fume hood, chemical laboratory safety rules
• TECHNICAL NOTE: the card of the standard has no scope, and laboratories apply spectrophotometry and potentiometry under one number; standard withdrawn since 2006 with no successor

Frequently asked questions