ISO 5622:2026

International
Standard
ISO 5622
First edition
Tobacco and tobacco products —
2026-06
Electrically heated tobacco products
(eHTPs) — Determination of carbon
monoxide in the vapour phase of
tobacco heating system aerosol by
NDIR method with a puffing regime
according to ISO 5501-1
Reference number
© ISO 2026
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus . 2
6 Reagents . 3
7 Procedure . 3
7.1 Conditioning.3
7.2 NDIR analyser calibration .3
7.3 Aerosolization and collection of the vapour phase .3
8 Expression of results . 4
8.1 Calculation of the average volume of carbon monoxide per consumable of tobacco
heating system .4
8.2 Calculation of the average mass of carbon monoxide per HTP .4
9 Repeatability and reproducibility . 5
10 Test report . 5
10.1 General .5
10.2 Product information about the samples and samples identification .5
10.3 Sampling .6
10.4 Description of test .6
10.5 Test results .6
Bibliography . 7

iii
Foreword
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The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
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This document was prepared by Technical Committee ISO/TC 126, Tobacco and tobacco products.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
Introduction
Tobacco heating systems (THS) are designed to heat a tobacco substrate, to produce a nicotine-containing
aerosol. A THS is a combination of a heated tobacco product (HTP) and a tobacco heating device (THD).
The HTP part of the THS is a product containing a tobacco substrate that is designed to be heated. This
combination significantly reduces toxicants, such as carbon monoxide.
With the emerging development and commercialisation of HTPs, there are a number of different approaches
to heating the HTP, categorised as electrically, aerosol and carbon, HTPs (eHTP, aHTP and cHTP), respectively
as described in ISO 6080.
Specific parameters and standard conditions for aerosol generation and collection from electrically heated
tobacco products have been described in ISO 5501-1.
Additionally, the expected level of carbon monoxide emissions from eHTPs is significantly lower than those
[1]
from cigarettes, necessitating a lower calibration range than that described in ISO 22947 .
[2]
The method in this document is based upon CORESTA recommended method CRM 108 which was written
on the basis of the results obtained in an interlaboratory study conducted in 2021 involving seventeen
laboratories and four THS samples. The results of this interlaboratory study were published by CORESTA in
[3]
a technical report HTP-280-CTR . The results showed repeatability and reproducibility values for aerosol
heated tobacco products (aHTPs) were not statistically relevant. Carbon heated tobacco products (cHTPs)
has not been commercially available.
This document defines and specifies the requirements for an electrically heated tobacco product (eHTP) for
the quantification of carbon monoxide in the vapour phase of the aerosol.
No machine puffing regime can represent all human puffing behaviour.
— It is recommended that eHTP also be tested under conditions of a different intensity of machine puffing
than those specified in this document.
— Machine puffing testing is useful to characterize eHTP emissions for design and regulatory purposes, but
communication of machine measurements to users can result in misunderstandings about differences in
exposure and risk across brands.
— Aerosol emission data from machine measurements may be used as inputs for product hazard
assessment, but they are not intended to be nor are they valid as measures of human exposure or risks.
Communicating differences between products in machine measurements as differences in exposure or
risk is a misuse of testing using ISO standards
IMPORTANT — This document is a reference document for ISO standards and measurement on tobacco
heating systems (e.g. ISO 6080). Regulation and standardisation are independent from each other, and
standardisation does not pre-empt regulation.

v
International Standard ISO 5622:2026(en)
Tobacco and tobacco products — Electrically heated tobacco
products (eHTPs) — Determination of carbon monoxide in
the vapour phase of tobacco heating system aerosol by NDIR
method with a puffing regime according to ISO 5501-1
WARNING — The use of this document can involve hazardous materials, operations and equipment.
This document does not purport to address all the safety problems associated with its use. It is the
responsibility of the user of this document to establish appropriate safety and health practices and
determine the applicability of any other restrictions prior to use.
1 Scope
This document specifies a method for the determination of carbon monoxide (CO) in the vapour phase of
tobacco heating system according to ISO 5501-1, by a non-dispersive infrared analyser (NDIR).
NOTE If tested products provide CO levels outside of the upper limit of the calibration range described in this
[1]
document, then the calibration range described in ISO 22947 applies.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 5501-1, Tobacco heating systems — Definitions and standard conditions for aerosol generation and
collection — Part 1: Electrically heated tobacco products (eHTPs)
ISO 6080, Toba
...