Fans - Vocabulary and definitions of categories (ISO/DIS 13349:2021)

Ventilatoren - Terminologie und Klassifizierung (ISO/DIS 13349:2021)

Ventilateurs - Vocabulaire et définitions des catégories (ISO/DIS 13349:2021)

Ventilatorji - Slovar in definicije kategorij (ISO/DIS 13349:2021)

General Information

Status
Not Published
Public Enquiry End Date
01-Oct-2021
Technical Committee
Current Stage
4020 - Public enquire (PE) (Adopted Project)
Start Date
22-Jul-2021
Due Date
09-Dec-2021

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SLOVENSKI STANDARD
oSIST prEN ISO 13349:2021
01-september-2021
Ventilatorji - Slovar in definicije kategorij (ISO/DIS 13349:2021)
Fans - Vocabulary and definitions of categories (ISO/DIS 13349:2021)
Ventilatoren - Terminologie und Klassifizierung (ISO/DIS 13349:2021)
Ventilateurs - Vocabulaire et définitions des catégories (ISO/DIS 13349:2021)
Ta slovenski standard je istoveten z: prEN ISO 13349
ICS:
01.040.23 Tekočinski sistemi in sestavni Fluid systems and
deli za splošno rabo (Slovarji) components for general use
(Vocabularies)
23.120 Zračniki. Vetrniki. Klimatske Ventilators. Fans. Air-
naprave conditioners
oSIST prEN ISO 13349:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 13349:2021
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oSIST prEN ISO 13349:2021
DRAFT INTERNATIONAL STANDARD
ISO/DIS 13349
ISO/TC 117 Secretariat: BSI
Voting begins on: Voting terminates on:
2021-07-16 2021-10-08
Fans — Vocabulary and definitions of categories
Ventilateurs — Vocabulaire et définitions des catégories
ICS: 23.120; 01.040.23
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 13349:2021(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. ISO 2021
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oSIST prEN ISO 13349:2021
ISO/DIS 13349:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved
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ISO/DIS 13349:2021(E)
Contents  Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2  Normative references ...................................................................................................................................................................................... 1

3  Terms and definitions ..................................................................................................................................................................................... 1

4  Symbols and units ............................................................................................................................................................................................10

4.1 Symbols ......................................................................................................................................................................................................10

4.2 Multiples of primary units .........................................................................................................................................................11

4.3 Units of time ...........................................................................................................................................................................................11

4.4 Temperature of air or gas ...........................................................................................................................................................11

5  Fan categories .......................................................................................................................................................................................................11

5.1 General ........................................................................................................................................................................................................11

5.2 Suitability for the fan pressure ...............................................................................................................................................11

5.2.1 Work per unit mass ....................................................................................................................................................12

5.2.2 Fan categories..................................................................................................................................................................12

5.2.3 Changes in air density ..............................................................................................................................................12

5.3 Suitability of construction ..........................................................................................................................................................12

5.3.1 Categorization according to casing construction .............................................................................12

5.3.2 Designation for hot-gas fan ..................................................................................................................................13

5.3.3 Designation and recommended categorization for smoke-ventilating fans .............13

5.3.4 Categorization for gas-tight fans .....................................................................................................................13

5.4 Transmission arrangements ....................................................................................................................................................14

5.5 Inlet and outlet conditions .........................................................................................................................................................18

5.6 Method of fan control .....................................................................................................................................................................18

5.7 Designation of direction of rotation and position of parts of the fan assembly ..........................19

5.7.1 General...................................................................................................................................................................................19

5.7.2 Direction of rotation ..................................................................................................................................................19

5.7.3 Outlet position of a centrifugal fan ................................................................................................................19

5.7.4 Position of component parts of a centrifugal fan with volute casing ..............................19

5.7.5 Position of component parts of an axial-flow, mixed-flow or other fan with

coaxial inlet and outlet ............................................................................................................................................20

5.7.6 Position of motor or other prime mover ..................................................................................................20

5.8 Characteristic dimensions and component parts ..................................................................................................20

5.8.1 Characteristic dimensions ....................................................................................................................................20

5.8.2 Terms for fan component parts ........................................................................................................................20

Annex A (informative) Examples ...........................................................................................................................................................................42

Bibliography .............................................................................................................................................................................................................................44

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ISO/DIS 13349:2021(E)
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 13349 was prepared by Technical Committee ISO/TC 117, Fans.

This second edition cancels and replaces the first edition (ISO 13349:2010), which has been technically

revised.
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Introduction

This International Standard reflects the importance of a standardized approach to the terminology of

fans.

The need for an International Standard has been evident for some considerable time. To take just one

example, the coding of driving arrangements differs from manufacturer to manufacturer. What one

currently calls arrangement no. 1 can be known by another as arrangement no. 3. The confusion for the

customer is only too apparent. For similar reasons, it is essential to use standardized nomenclature to

identify particular parts of a fan.

Wherever possible, in the interests of international comprehension, this International Standard is in

agreement with similar documents produced by Eurovent, AMCA, VDMA (Germany), AFNOR (France)

and UNI (Italy). They have, however, been built on where the need for amplification was apparent.

Use of this International Standard will lead to greater understanding among all parts of the air-

moving industry. This International Standard is intended for use by manufacturers, consultants and

contractors.
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oSIST prEN ISO 13349:2021
DRAFT INTERNATIONAL STANDARD ISO/DIS 13349:2021(E)
Fans — Vocabulary and definitions of categories
1 Scope

This International Standard defines terms and categories in the field of fans used for all purposes.

It is not applicable to electrical safety.
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 5167-1, Measurement of fluid flow by means of pressure differential devices inserted in circular cross-

section conduits running full — Part 1: General principles and requirements
ISO 5801:2017, Fans — Performance testing using standardized airways
ISO 5802:2001, Industrial fans — Performance testing in situ

ISO/CD 12759-1, Fans — Efficiency classification for fans — Part 1:General information for fans

ISO 13351, Fans — Dimensions
3  Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 5167-1 and ISO 5801 and the

following apply
3.1
Fan

rotary-bladed machine that receives mechanical energy and utilizes it by means of one or more

impellers fitted with blades to maintain a continuous flow of air or other gas passing through it and

whose work per unit mass does not normally exceed 25 kJ/kg

Note 1 to entry: The term “fan” is taken to mean the fan as supplied, without any addition to the inlet or outlet,

except where such addition is specified.

Note 2 to entry: Fans are defined according to their installation category, function, fluid path and operating

conditions.

Note 3 to entry: If the work per unit mass exceeds a value of 25 kJ/kg, the machine is termed a turbocompressor.

This means that, for a mean stagnation density through the fan of 1,2 kg/m , the fan pressure does not

exceed 1,2 × 25 kJ/kg, i.e. 30 kPa, and the pressure ratio does not exceed 1,30 since atmospheric pressure is

approximately 100 kPa.
3.1.1
non-driven Fan
a fan without motors, drives, attachments or accessories
Note 1 to entry: Also known as Bare Shaft Fan.
See ISO 12759-1.
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3.1.2
driven fan

a fan driven by an electrical motor. One or more impellers fitted to or connected to a motor with a

stationary element, with or without transmission or variable speed drive.
[SOURCE: See ISO 12759-1.]
3.1.3
fan integrated (embedded) in other energy related products
fan which is an integral part of another product
3.1.4
term for Stand Alone Fan

a fan what is used as a unique entity and integrated into any other product, it may or may not have

ducting connected to its inlet and outlet
3.2
Air
abbreviated term for the expression “air or other gas”
3.3
Standard air
by convention, air with a density of 1,2 kg/m
3.4  Fan installation categories according to the arrangement of ducting
[SOURCE: See Figure 1.]
3.4.1
installation category A
installation with free inlet and free outlet with a partition
[SOURCE: See ISO 5801 and ISO 5802.]
3.4.2
installation category B
installation with free inlet and ducted outlet
[SOURCE: See ISO 5801 and ISO 5802.]
3.4.3
installation category C
installation with ducted inlet and free outlet
[SOURCE: See ISO 5801 and ISO 5802.]
3.4.4
installation category D
installation with ducted inlet and ducted outlet
[SOURCE: See ISO 5801 and ISO 5802.]
3.4.5
installation category E
installation with free inlet and free outlet without a partition
3.5  Types of fan according to their development and application
3.5.1
custom designed fan
fan developed and produced for one single application
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3.5.2
standardised fan

fan whose detailed performance is widely available in a catalogue (electronic and/or printed),and

which is frequently manufactured in quantity
3.6  Types of fan according to their function
3.6.1
ducted fan
fan used for moving air within a duct

Note 1 to entry: This fan can be arranged in installation category B, C or D (see Figures 3, 4, 5 and 6).

3.6.2
partition fan

fan used for moving air from one free space to another, separated from the first by a partition having an

aperture in which or on which the fan is installed

Note 1 to entry: This fan can be arranged in installation category A (see Figure 7).

3.6.3
jet fan
fan used for producing a jet of air in a space and unconnected to any ducting
[SOURCE: See Figure 8.]

Note 1 to entry: The air jet can be used, for example, for adding momentum to the air within a duct, a tunnel or

other space, or for intensifying the heat transfer in a determined zone.
3.6.4
circulating fan
fan used for moving air within a space which is unconnected to any ducting
[SOURCE: See Figure 9.]
3.6.5
air curtain unit
air moving device which produces an air curtain
[SOURCE: See Figure 31.]
3.6.5.1
air curtain
airstream

directionally controlled airstream, moving across the entire height and width of an opening, which can

reduce the infiltration or transfer of air from one side of the opening to the other, and inhibits insects,

dust or debris from passing through
3.7  Fan types according to the fluid path within the impeller

fan of specific and typical design primarily distinguished by the geometry of its impeller and the

resulting gas path through the fan
3.7.1
axial, mixed flow and centrifugal fan

fan types are identified by the angles α, average value of the angles α1 and α2 (see Figure 2)

α = (α1 + α2)/2
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The angle α1 is the angle of the tangent at the hub at the intersection of the blade trailing edge with the

hub. The angle α2 is the angle of the tangent at the shroud or at the outer diameter of the blade at the

intersection of the blade trailing edge with the shroud or with the outer diameter of the blade. If the

hub and/or shroud are not axisymmetric, angles α1 and α2 are the average values in circumferential

direction. The fan types are defined as in Table 1.
Table 1 — Fan type defined by the relationship of the blade and the shroud/hub
Fan type Angle α
Axial fan α < 20°
Mixed flow fan 20° ≤ α < 70°
Centrifugal fan 70° ≤ α

Note 1 to entry: Centrifugal fans contain the types ‘centrifugal radial bladed fan’ (including radial tip), ‘centrifugal

forward curved fan’ and ‘centrifugal backward curved fan’ (including also backward inclined and backward

curved aerofoil bladed fans).
3.7.2
axial fan

axial-flow fan in which the air enters and leaves the impeller along essentially cylindrical surfaces

coaxial with the fan
[SOURCE: See Figure 4.]

Note 1 to entry: An axial-flow fan can be of the low-, medium- or high-pressure type, according to the aspect ratio

of hub diameter to outside impeller diameter. These terms indicate that the pressure generated at a given flow

rate is low, medium or high.

Note 2 to entry: Figure 11 shows a cross-section through a family of impellers having the same outside diameter.

Fans with ratios of hub/outside impeller diameter of less than approximately 0,4 mm are considered “low aspect

ratio”, and greater than approximately 0,71 mm are considered “high aspect ratio”. Medium aspect ratio axial

fans are intermediate between these two figures.

Note 3 to entry: These categories are also affected by the ability to run at the necessary peripheral speed.

3.7.2.1
contra-rotating fan

axial-flow fan which has two impellers arranged in series and rotating in opposite directions

[SOURCE: See Figure 33.]
3.7.2.2
reversible axial-flow fan

axial-flow fan that is specially designed to rotate in either direction, regardless of whether or not the

performance is identical in both directions
3.7.2.3
propeller fan

axial-flow fan having an impeller with a small number of broad blades of uniform material thickness

and designed to operate in an orifice
3.7.2.4
plate-mounted axial-flow fan

axial-flow fan in which the impeller rotates in an orifice or spigot of relatively short axial length, the

impeller blades being of aerofoil section
3.7.2.5
vane-axial fan

axial-flow fan suitable for ducted applications, which has guide vanes before or after the impeller, or

both
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3.7.2.6
tube-axial fan
axial-flow fan without guide vanes, suitable for ducted applications
3.7.3
mixed-flow fan

fan in which the fluid path through the impeller is intermediate between the centrifugal and axial-flow

types
Note 1 to entry: also known as diagonal flow fan.
[SOURCE: See Figures 6 and 12.]
3.7.4
centrifugal fan

fan in which the air enters the impeller with an essentially axial direction and leaves it in a direction

perpendicular, or near perpendicular to this axis (see Table 1 and Figures 2,3)
Note 1 to entry: The centrifugal fan is also known as a radial-flow fan.

Note 2 to entry: The impeller can have one or two inlet(s) and might include a shroud and/or a backplate

(centreplate) (see Figure 17).

Note 3 to entry: The impeller is defined as “backward-curved or inclined”, “radial” or “forward-curved”,

depending on whether the outward direction of the blade at the periphery is backward, radial or forward relative

to the direction of the rotation (see Figures 10 and 17).

Note 4 to entry: A centrifugal fan can be of the low-, medium- or high-pressure type, according to the aspect ratio

of fan inlet diameter to outside diameter of the impeller. These terms indicate that the pressure generated at a

given flow rate is low, medium or high.

Note 5 to entry: Figure 10 shows a cross-section through a family of impellers having the same inlet diameter.

Fans with ratios of fan inlet/outside impeller diameter of greater than approximately 0,63 mm are considered

“low aspect ratio”, and lower than approximately 0,4 mm are considered “high aspect ratio”. Medium aspect ratio

centrifugal fans are intermediate between these two.

Note 6 to entry: The impeller diameter and the casing scroll radii increase with the pressure range for which the

fan is designed.

Note 7 to entry: These categories are also affected by the ability to run at the necessary peripheral speed (see 5.2

and Table 2).
3.7.5
cross flow fan (tangential fan)

fan in which the fluid path through the impeller is in a direction essentially at right angles to its axis

both entering and leaving the impeller at its periphery
[SOURCE: See Figure 13.]
3.7.6
induced flow fan

housed fan with a nozzle and windband whose outlet airflow is greater than its inlet airflow due to

induced airflow

Note 1 to entry: All of the flow entering the inlet will exit through the nozzle, the flow exiting the windband will

include the nozzle flow plus the induced flow.

Note 2 to entry: Windband can also referred to as an airflow accelerator or venturi.

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3.7.7
peripheral or side channel fan

air moving device for which the circulation of fluid in the toric casing is helicoidal

Note 1 to entry: The rotation of the impeller, which contains a number of blades, creates a helicoidal trajectory,

which is intercepted by one or more blades depending on the flow rate. The impeller transfers energy to the fluid

(see Figure 16).
3.7.8
multi-stage fan
fan having two or more impellers working in series
EXAMPLE A two-stage fan or a three-stage fan.

Note 1 to entry: Multi-stage fans can have guide vanes and interconnecting ducts between successive impellers.

Note 2 to entry: The blades of an impeller can be either of a profiled section (as an aerofoil) or of uniform

thickness (see Figure 17).
3.7.9
in-line centrifugal fan
fan having a centrifugal impeller used in an in-line ducted configuration
[SOURCE: See Figure 5.]
3.7.10
bifurcated fan

fan having an axial-flow, mixed-flow or centrifugal impeller in an in-line configuration where the direct-

drive motor is separated from the flowing air stream by means of a compartment or tunnel

[SOURCE: See Figure 28 c).]
3.7.11
plug fan

fan having an unhoused impeller arranged such that the system into which it is inserted acts as a

housing, allowing air to be drawn into the impeller inlet
[SOURCE: See Figure 14.]
3.7.12
plenum fan

fan having an unhoused centrifugal impeller which draws air into the impeller through an inlet located

in a barrier wall, and having a driver located on the same side of the barrier as the impeller

[SOURCE: See Figure 15.]
3.7.13
in-line and box fan
fan that incorporates centrifugal/mixed-flow impellers
[SOURCE: See Figures 5 and 31.]
3.8  Types of fan according to operating conditions
3.8.1
general-purpose fan

fan suitable for handling air which is non-toxic, unsaturated, non-corrosive, non-flammable, free from

abrasive particles and within a temperature range from −20 °C to +80 °C

Note 1 to entry: For temperatures greater than 40 °C, the motor is especially taken into consideration.

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3.8.2
special-purpose fan
fan used for special operating conditions
[SOURCE: See 3.8.2.1 to 3.8.2.12.]
Note 1 to entry: A fan can have a combination of special features.

Note 2 to entry: The operating conditions stated below (3.8.2.1 to 3.8.2.12) represent a typical range, but the

list is not necessarily complete. It is intended that the manufacturer and purchaser agree on other types having

special features to suit specific applications.
3.8.2.1
hot-gas fan
fan used for handling hot gases continuously

Note 1 to entry: Special materials can be incorporated, as necessary, for the fan which can have a direct or

indirect drive.

Note 2 to entry: The motor on a direct-drive fan can be either in the air stream or separated from it.

Note 3 to entry: Indirect-drive fans can incorporate a means for cooling belts, bearings or other drive components,

where necessary (for designation, see 5.3.2).
3.8.2.2
smoke-ventilating fan
fan suitable for handling hot smoke for a specified time/temperature profile

Note 1 to entry: Special materials can be incorporated, as necessary, for the fan, which can have a direct or

indirect drive.

Note 2 to entry: The motor can be either in the air stream on a direct-drive fan or separated from it.

Note 3 to entry: Indirect-drive fans incorporate a means for cooling belts, bearings or other drive components,

where necessary (for designation, see 5.3.2).
3.8.2.3
wet-gas fan
fan suitable for handling air containing particles of water or any other liquid
3.8.2.4
gas-tight fan

fan with a suitably sealed casing to match a specified leakage rate at a specified pressure

Note 1 to entry: Depending upon the leakage specification, this can involve special attention being paid to all

services which penetrate the casing, such as inspection means, lubricator fittings and electrical supply, as well as

the details of the connecting flanges (for categorization, see 5.3.4).
3.8.2.5
dust fan

fan suitable for handling dust-laden air, designed to suit the dust being handled

3.8.2.6
conveying fan
transport fan

fan suitable for the conveying of solids and dust entrained in the air stream, designed to suit the

material being conveyed

Note 1 to entry: A conveying/transport fan can be of direct or indirect drive type, depending on whether or not

the handled material passes through the impeller.

Note 2 to entry: Examples of solids are wood chips, textile waste and pulverized materials.

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3.8.2.7
non-clogging fan

fan having an impeller designed to minimize clogging by virtue of its detailed shape or by the use of

special materials

Note 1 to entry: The fan can also incorporate other features to allow the use of cleaning sprays and facilitate the

removal of any material.
3.8.2.8
abrasion-resistant fan

fan designed to minimize abrasion, having parts that are especially subject to wear, constructed from

suitably abrasion-resistant materials and easily replaceable
3.8.2.9
corrosion-resistant fan

fan constructed from suitably corrosion-resistant materials or suitably treated to minimize corrosion

by specified agents
3.8.2.10
spark-resistant fan
ignition-protected fan

fan with features designed to minimize the risk of sparks or hot spots resulting from contact between

moving and stationary parts that may cause the ignition of dust or gases

Note 1 to entry: No bearings, drive components or electrical devices are placed in the air or gas stream, unless

they are constructed in such a manner that failure of that component cannot ignite the surrounding gas stream

(for categorization, see 5.3.4).
3.8.2.11
powered-roof ventilator
fan designed for mounting on a roof and having exterior weather protection
3.8.2.12
positive-pressure ventilator

portable fan that can be positioned relative to an opening of a confined space and cause it to be positively

...

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