🌿 Testing of cleanrooms and clean zones — test methods supplementary to air cleanliness classification according to ISO 14644-1: differential pressure (4.2.1/B.1), airflow and air change rate (4.2.2/B.2), airflow direction and visualization (4.2.3/B.3), recovery time after brief exposure to an aerosol (4.2.4/B.4), temperature (4.2.5/B.5), humidity (4.2.6/B.6), installed filter leakage by scanning with a particle counter or aerosol photometer (4.2.7/B.7), containment leakage (4.2.8/B.8), electrostatic and ion generator tests (4.2.9/B.9), particle deposition (4.2.10/B.10) and segregation (4.2.11/B.11); the selection of tests is agreed between customer and supplier, PN-EN ISO 14644-3

Environment PN-EN ISO 14644-3

Overview

WHAT THE STANDARD COVERS. We read the text of the standard in two iTeh samples. The SIST EN ISO 14644-3:2020 sample (English text) covers the European foreword, the endorsement notice, the ISO foreword, introduction, Clauses 1–2 and Clause 3 up to definition 3.3.2. The ISO 14644-3:2019 sample (French text, corrected version 2020-06) additionally covers all definitions (3.1–3.7) and Clause 4 up to and including 4.2.11, up to page 9. We do not read Clause 5 (test report) or Annexes A (selection of tests and checklist), B (supplementary test methods) and C (test apparatus) — we know the titles from the contents. The actual measurement procedures are in Annex B.

ACCORDING TO THE TEXT OF ISO 14644-3:2019 AND EN ISO 14644-3:2019. The standard was prepared by ISO/TC 209 “Cleanrooms and associated controlled environments” in collaboration with CEN/TC 243 “Cleanroom technology” (secretariat BSI); national standards had to adopt it by April 2020 at the latest; EN ISO 14644-3:2019 supersedes EN ISO 14644-3:2005. The second edition replaces ISO 14644-3:2005 after technical revision: Annex B.7 (filter leakage) was simplified and corrected because of its complexity and reported errors, guidance on classification of airborne particle cleanliness was moved to ISO 14644-1, and the text as a whole was revised. The corrected version 2020-06 corrects references in Table A.1, B.4.4, C.1, C.4.2 and C.4.3, the wording in B.2.1 a) and Table B.2, and deletes the former Figure B.2. Introduction: cleanrooms serve, among others, aerospace, microelectronics, pharmaceuticals, medical devices, healthcare and the food industry; the standard describes methods for measuring the performance of a cleanroom, clean zone or controlled environment, including separative devices, structures, air-handling systems and services; note: it does not cover all tests — classification of airborne particle cleanliness and macroparticles are in ISO 14644-1, monitoring of nanoscale particles in ISO 14644-12, biocontamination in the ISO 14698 series, commissioning in ISO 14644-4, separative devices in ISO 14644-7, air chemical cleanliness in ISO 14644-8, surface particle cleanliness in ISO 14644-9, surface chemical cleanliness in ISO 14644-10. Scope (1): test methods for the performance of cleanrooms and clean zones in order to meet air cleanliness classification, other cleanliness attributes and associated controlled conditions; tests for two types of airflow — unidirectional and non-unidirectional — and three occupancy states: as-built, at-rest and operational; for some tests several methods and instruments; alternative methods not in the standard by agreement between customer and supplier, although they do not necessarily give equivalent results; the standard does not apply to measurements on products or processes in cleanrooms; it does not deal with health and safety. There are no normative references (2). Definitions (3): e.g. clean zone, installation, separative device (e.g. clean air hoods, containment enclosures, glove boxes, isolators, “mini-environnements”), resolution and sensitivity, airborne particle (from 1 nm to 100 µm), test aerosol, designated leak (maximum penetration detectable when scanning a filter installation with an LSAPC particle counter or aerosol photometer, agreed between customer and supplier), terminal filter, filter leak, scanning (moving the probe in overlapping passes), air change rate (volume of supply air per unit time divided by the volume of the room), unidirectional and non-unidirectional airflow, velocity uniformity, discharge time and induced voltage, aerosol generator (particles e.g. 0,05–2 µm), aerosol photometer (mass concentration by light scattering), capture hood with an instrument for direct measurement of supply airflow, LSAPC (requirements in ISO 21501-4), witness plate, three occupancy states. Clause 4.1: ISO 14644-1 is used for classification by airborne particle concentration; other cleanliness attributes are selected according to Table 1 (ISO 14644-8, -9, -10, -12); Table 2 lists the supplementary tests with references to the principle (4.2), procedure (Annex B) and apparatus (Annex C); the tests can be applied in each of the three states, not all are required for a given project, the selection is agreed between customer and supplier, and they may be repeated in routine monitoring; guidance on selection and a checklist are given in Annex A; the methods in Annex B are described only in outline. Principles (4.2): 4.2.1 differential pressure — checks the ability of the system to maintain the specified differential pressure between the cleanroom and its surroundings; performed after the criteria for supply air velocity or volume flow and uniformity have been met; 4.2.2 airflow — for unidirectional flow point velocity measurements (giving uniformity, volume flow and air change rate), for non-unidirectional flow usually direct measurement of supply volume flow; 4.2.3 airflow direction and visualization — at rest, possibly repeated in operation; 4.2.4 recovery test — whether the cleanroom returns to the specified cleanliness class within a finite time after brief exposure to a test aerosol; not recommended for unidirectional flow; with an artificial aerosol the risk of residues must be considered; 4.2.5 and 4.2.6 temperature and humidity (relative or dew point) — within control limits for the period specified by the customer; 4.2.7 installed filter leakage — confirms correct installation of terminal high-efficiency filters: absence of bypass and filter defects (pinholes, damage to the medium, frame, gasket, leaks in the bank frame); not intended to determine the efficiency of the filter medium; aerosol introduced upstream and scanning downstream of the filter or sampling in a duct downstream; 4.2.8 containment leakage — ingress of unfiltered air from outside through joints, connections, doors and ceilings; 4.2.9 electrostatic and ion generator tests; 4.2.10 particle deposition — amount and size of airborne particles deposited on a surface over an agreed period (may be regarded as a test in the operational state); 4.2.11 segregation — effectiveness of segregation by a given airflow: particles are generated in the zone of lower class and the concentration measured in the protected zone.

STATUS (as of 03.10.2026). In the PKN search (term “14644-3”, 03.10.2026) PN-EN ISO 14644-3:2020-03 (English version, “Introduces: EN ISO 14644-3:2019 [IDT], ISO 14644-3:2019 [IDT]”) has no withdrawal note; PN-EN ISO 14644-3:2006 (English version) has the note “Withdrawn and replaced by PN-EN ISO 14644-3:2020-03”. Card: publication date 13.03.2020, 66 pages, KT 161 Indoor Air Quality, ICS 13.040.35, “Replaces PN-EN ISO 14644-3:2006 – English version”. In the iTeh catalogue (read 03.10.2026) ISO 14644-3:2019 has the status “Published”, stage 90.60 (close of review), published 30.08.2019; SIST EN ISO 14644-3:2020 — “Published”, replaces SIST EN ISO 14644-3:2006. There is no Polish language version of the standard.

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database, load up to 17.09.2026, read 03.10.2026). The number 14644-3 appears in 15 records at 2 laboratories: AB 243 (8), AB 752 (7). In the current PCA documents (read 03.10.2026; AB 243 issue No. 27 of 09.12.2025, AB 752 issue No. 26 of 08.07.2026) the number appears in 15 lines at the same 2 laboratories (8 and 7); in each document the number of page markers equals the number of PDF pages, without repetitions; a search of all PCA documents downloaded from the BIP on 03.10.2026 found no laboratories outside the database copy. Form “PN-EN ISO 14644-3:2020-03 pkt. … i załącznik B.…” (AB 243) and “PN-EN ISO 14644-3:2020 pkt. … i załącznik B.…” (AB 752) — always with the clause number of the principle and the annex; for filter leakage alongside PN-EN 1822-1:2019-05 clauses 5 and 6, at AB 243 for cleanliness and recovery time alongside PN-EN ISO 14644-1:2016-03. None of these items is suspended. The “Laboratories” tab (term “PN-EN ISO 14644-3”) shows both laboratories — checked by a tab query on the labcoda.pl production server on 03.10.2026.

WHAT THE LABORATORIES TEST (items in PCA). Objects: “Workplace environment – air”, “Air filter”, “Ventilation”, “Cleanrooms and laminar flow cabinets”. AB 243: cleanliness — number of particles of 0,1; 0,2; 0,3; 0,5; 1,0; 5,0 µm, from 1 to 349 999 965 particles/m³, with a particle counter (4.2.10/B.10 with PN-EN ISO 14644-1); time to reach initial air cleanliness (4.2.4/B.4); temperature (+5…+42) °C; relative humidity (10–85) % RH; differential pressure (−2500…+2500) Pa; uniformity of the filter medium (leak test) and tightness of filter mounting — with a linear photometer (4.2.7/B.7); air velocity (0,2–40) m/s and volume flow (50–2000) m³/h for the air change rate, by indirect and direct methods (4.2.2/B.2); penetration — particle mass concentration with a linear photometer (4.2.8/B.8). AB 752: time to reach initial cleanliness (particles of 0,1; 0,3; 0,5; 1,0; 3,0; 5,0 µm, (1–9 999 999) particles/ft³ or (35–349 999 965) particles/m³, time measurement in min and with a counter); differential pressure (−2500…+2500) Pa; temperature (−40…+70) °C; relative humidity (0–90) %; penetration and integrity and tightness of filter mounting — with a particle counter (with a 1:100 diluter) and a linear photometer; air velocity (0,2–40) m/s and volume flow (50–2000) m³/h. AB 752 performs air cleanliness classification in a separate item according to PN-EN ISO 14644-1:2016-03 alone.

WHERE AN APPARENTLY CORRECT RESULT IS EASY TO GET. With classification: the airborne particle cleanliness class is determined according to ISO 14644-1 (4.1.1), and the classification guidance was moved from this standard to ISO 14644-1 (foreword); clause 4.2.10 and Annex B.10 concern particle deposition on a surface over an agreed period, not counting particles in air — AB 243 assigns to 4.2.10/B.10 an item “Cleanliness” with the number of particles in air and a particle counter, alongside PN-EN ISO 14644-1. With recovery time: the test is not recommended for unidirectional flow, and an artificial aerosol may leave residues (4.2.4). With filters: the installed filter leakage test does not determine the efficiency of the filter medium (4.2.7); the designated leak is agreed between customer and supplier (3.3.2); procedure B.7 was simplified and corrected in the 2019 edition (foreword) — anyone working to old instructions is working to a different text. With order: differential pressure is measured only after the criteria for supply air velocity or volume flow and uniformity have been met (4.2.1). With the occupancy state: a result is meaningful only with the stated state — as-built, at-rest or operational (1, 3.7). With the selection of tests: not all tests are required and their selection is agreed between customer and supplier; alternative methods do not necessarily give equivalent results (1, 4.1.2). With units in PCA: the text layer of both PCA documents loses the µ sign (and the degree sign of °C) and gives “(0,0003 - 100) g/l”, but on the page images (AB 243 p. 2, AB 752 p. 8) the mass concentration for the photometer has the unit µg/l; the database copy gives µg/l at AB 243 and “g/l” at AB 752 — an error of the copy.

WHAT WE DO NOT GIVE. We do not quote the measurement procedures of Annex B (number and location of points, measurement times, aerosol concentrations, leak criteria), the apparatus requirements of Annex C, the checklist of Annex A or the content of the test report (5) — they lie outside the samples. We have not read ISO 14644-1, ISO 14644-4, ISO 14644-7 or PN-EN 1822-1. We do not give GMP requirements for room classes.

Method principle

A cleanroom is classified by the concentration of airborne particles (ISO 14644-1), and its performance is checked by supplementary tests selected by customer and supplier: measurement of differential pressure, airflow and air change rate, airflow direction, recovery time after brief aerosol exposure, temperature and humidity, installed filter leakage (aerosol upstream, scanning downstream with a particle counter or aerosol photometer), containment leakage, electrostatics, particle deposition and segregation. Tests are performed in a stated occupancy state: as-built, at-rest or operational.

Applications

• Acceptance and periodic testing of cleanrooms and clean zones with unidirectional and non-unidirectional airflow (1)
• Installations in pharmaceuticals, medical devices, microelectronics, healthcare and the food industry (introduction)
• Workplace environment, air filters, ventilation, cleanrooms and laminar flow cabinets — 15 items in the accreditation scopes of 2 laboratories in PCA

Key parameters

Standard

Standard number

PN-EN ISO 14644-3:2020-03

Title (PL)

Pomieszczenia czyste i związane z nimi środowiska kontrolowane — Część 3: Metody badań

Title (EN)

Cleanrooms and associated controlled environments — Part 3: Test methods

Step-by-step procedure

1. Agreeing the scope

   Selection of tests, methods, occupancy state and criteria (e.g. designated leak) between customer and supplier; guidance in Annex A (4.1.2). PN-EN ISO 14644-3:2020-03 without a withdrawal note in PKN (03.10.2026).

2. Cleanliness classification

   Airborne particle concentration according to ISO 14644-1 (4.1.1).

3. Airflow and pressures

   Supply air velocity or volume flow and uniformity, then differential pressure; airflow direction (4.2.2, 4.2.1, 4.2.3; procedures B.1–B.3 outside the sample).

4. Filters and enclosure

   Scanning of installed filters, containment leakage (4.2.7, 4.2.8; B.7, B.8 outside the sample).

5. Other tests and report

   Recovery time, temperature, humidity, electrostatics, particle deposition, segregation; report with occupancy state (4.2.4–4.2.11; Clause 5 outside the sample).

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• The standard does not deal with health and safety (1, note) — obligations are set by the user
• Test aerosol may contaminate the room with residues (4.2.4)

Frequently asked questions