ISO 29042-9:2011

INTERNATIONAL ISO
STANDARD 29042-9
First edition
2011-01-15
Safety of machinery — Evaluation of the
emission of airborne hazardous
substances —
Part 9:
Decontamination index
Sécurité des machines — Évaluation de l'émission de substances
dangereuses véhiculées par l'air —
Partie 9: Indice d'assainissement

Reference number
©
ISO 2011
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.

©  ISO 2011
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2011 – All rights reserved

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 29042-9 was prepared by Technical Committee ISO/TC 199, Safety of machinery.
ISO 29042 consists of the following parts, under the general title Safety of machinery — Evaluation of the
emission of airborne hazardous substances:
⎯ Part 1: Selection of test methods
⎯ Part 2: Tracer gas method for the measurement of the emission rate of a given pollutant
⎯ Part 3: Test bench method for the measurement of the emission rate of a given pollutant
⎯ Part 4: Tracer method for the measurement of the capture efficiency of an exhaust system
⎯ Part 5: Test bench method for the measurement of the separation efficiency by mass of air cleaning
systems with unducted outlet
⎯ Part 6: Test bench method for the measurement of the separation efficiency by mass of air cleaning
systems with ducted outlet
⎯ Part 7: Test bench method for the measurement of the pollutant concentration parameter
⎯ Part 8: Room method for the measurement of the pollutant concentration parameter
⎯ Part 9: Decontamination index
Introduction
The structure of safety standards in the field of machinery is as follows:
a) Type-A standards (basic safety standards) giving basic concepts, principles for design, and general
aspects that can be applied to all machinery;
b) Type-B standards (generic safety standards) dealing with one safety aspect or one type of safeguard that
can be used across a wide range of machinery:
⎯ type-B1 standards on particular safety aspects (e.g. safety distances, surface temperature, noise);
⎯ type-B2 standards on safeguards (e.g. two-hand controls, interlocking devices, pressure-sensitive
devices, guards);
c) Type-C standards (machine safety standards) dealing with detailed safety requirements for a particular
machine or group of machines.
This document is a type-B standard as stated in ISO 12100.
The requirements of this document can be supplemented or modified by a type-C standard.
For machines which are covered by the scope of a type-C standard and which have been designed and built
according to the requirements of that standard, the requirements of that type-C standard take precedence.
ISO/TC 199 has a mandate in this area to produce type-A and type-B standards, which will allow verification
of conformity with the essential safety requirements.
ISO 29042-9 is based on EN 1093-11:2001, amended by Amendment 1:2008, published by the European
Committee for Standardization (CEN).

iv © ISO 2011 – All rights reserved

INTERNATIONAL STANDARD ISO 29042-9:2011(E)

Safety of machinery — Evaluation of the emission of airborne
hazardous substances —
Part 9:
Decontamination index
WARNING — It should be observed that during the test, especially during the shutdown or the
removal of the pollutant control system, the concentration of hazardous substances, if present, can
reach levels which are liable to incur a risk to the health of the operators or other occupants present
in the room.
This part of ISO 29042 does not deal with the protective measures required to control these risks.
1 Scope
This part of ISO 29042 specifies a method for the measurement of the decontamination index of pollutant
control systems, e.g. capture devices including local exhaust ventilation, water spray systems and, when
appropriate, separation equipment installed on a machine. This method uses the real pollutant (see
ISO 29042-1:2008, 4.2) and can be operated in room or field environments.
Measurement of the decontamination index of a pollutant control system can serve for the:
a) evaluation of the performance of a pollutant control system of a machine;
b) evaluation of the improvement of a pollutant control system;
c) comparison of pollutant control systems for machines of similar design;
d) ranking of pollutant control systems according to their decontamination efficiency;
e) determination of the air flow rate in the case of an exhaust system to achieve a given level;
f) determination of the state of the art of pollutant control systems for machines with respect to the
decontamination efficiency.
2 Normative references
The following referenced documents are indispensable for the application 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 12100, Safety of machinery — General principles for design — Risk assessment and risk reduction
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12100 and the following apply.
3.1
decontamination index
I
A
average of the ratio, obtained at a number of specified locations in the surroundings, of the ambient air quality
improvement to the real pollutant mean concentration with the pollutant control system not in operation
NOTE 1 Corrections can be necessary to take into account air pollution caused by other operations (“the background
level”).
NOTE 2 The ambient air quality improvement is given by the difference between the real pollutant concentrations
measured in these surroundings with and without the pollutant control system in operation.
NOTE 3 When particle size distribution is determined at the same time as pollutant concentration, a decontamination
index for each size fraction can be determined. See, for example, ISO 7708.
4 Principle
The principle of this measurement method consists in determining the decontamination index as defined in 3.1,
the concentrations being measured at predetermined points around the machinery under inspection and in
interpreting the value of this index, taking into account its range of variation and the influencing factors.
5 Determination of concentration measurement points
The measurement points shall be determined by pre-testing to ensure that they are in zones of measurable
emission. The number and precise positions shall be specified in type-C standards.
6 Test method
6.1 General
The measurement is more accurate and the interpretation more reliable if the background level concentration
is low. Whenever possible, the concentration measurements should be taken with the surrounding machinery
and other processes shut down.
Once the locations of the measurement points have been selected, the measurement procedure takes place
in three phases (see 6.2 to 6.4
...