prEN 54-20

Fire detection and fire alarm systems - Part 20: Aspirating smoke detectors

This European standard specifies the requirements, test methods and performance criteria for aspirating smoke detectors for use in fire detection and fire alarm systems installed in or around buildings or other civil engineering works.
This European standard provides for the assessment and verification of constancy of performance (AVCP) of aspirating smoke detectors to this EN. Aspirating smoke detectors developed for the protection of specific risks that incorporate special characteristics (including additional features or enhanced functionality for which this standard does not define a test or assessment method) are also covered by this standard. The performance requirements for any special characteristics are beyond the scope of this standard.
NOTE   Certain types of detector contain radioactive materials. The national requirements for radiation protection differ from country to country and they are not therefore specified in this standard.

Brandmeldeanlagen - Teil 20: Ansaugrauchmelder

Systèmes de détection et d'alarme incendie - Partie 20 : Détecteurs de fumée par aspiration

Sistemi za odkrivanje in javljanje požara ter alarmiranje - 20. del: Aspiracijski dimni javljalniki

General Information

• Status: Not Published
• Publication Date: 13-Dec-2015
• Withdrawal Date: 13-Jun-2016
• ICS: 13.220.20 - Fire protection
• Technical Committee: CEN/TC 72 - Fire detection and fire alarm systems
• Drafting Committee: CEN/TC 72/WG 16 - Aspirating smoke detectors
• Current Stage: 4098 - Decision to abandon - Enquiry
• Start Date: 06-Mar-2015
• Completion Date: 14-Apr-2025
• Directive: 305/2011 - Regulation (eu) No 305/2011 of the European Parliament and of the Council of 9 march 2011 laying down harmonised conditions for the marketing of construction products and repealing council directive 89/106/eec
• Mandate: M/109 - Mandate to CEN/CENELEC concerning the execution of standardization work for harmonized standards on fire alarm/detection, fixed firefighting, fire and smoke control and explosion suppression products
• Ref Project: oSIST prEN 54-20:2014 - Fire detection and fire alarm systems - Part 20: Aspirating smoke detectors

Relations

• Revises: EN 54-20:2006 - Fire detection and fire alarm systems - Part 20: Aspirating smoke detectors
• Effective Date: 18-Jan-2023

Overview

The European Standard prEN 54-20 specifies requirements and performance criteria for aspirating smoke detectors (ASDs) used in fire detection and fire alarm systems for buildings and civil engineering works. Developed by CEN/TC 72, this standard outlines essential test methods, design considerations, and verification procedures to ensure reliable early fire detection. It supersedes the earlier EN 54-20:2006 standard and updates testing protocols and performance verification aligned with EU Construction Products Regulation 305/2011.

This standard focuses on the assessment and verification of constancy of performance (AVCP) of ASDs, including units designed for specific risks with enhanced or special functionalities, although performance requirements for these extra features are beyond its scope.

Key Topics

• Scope and Application
  The standard applies to ASDs that draw air samples through a network of sampling pipes to detect smoke. These devices are integral to active fire detection systems installed indoors or in critical outdoor civil infrastructure.

• Terminology and Definitions
  Includes key terms like aspirating smoke detector, sampling device, response value, and design tools used for sensitivity classification.

• Performance Requirements

  • Nominal Activation Conditions & Sensitivity: Visual alarm indicators must be clearly visible and distinguishable for each smoke sensing element.
  • Repeatability and Reproducibility: ASDs must maintain stable sensitivity over multiple alarms and consistent sensitivity between samples.
  • Response to Slowly Developing Fires: Devices with drift compensation must still reliably detect slow fires without sensitivity loss.

• Sensitivity Classification
  Three classes define detection performance:

  • Class A: Very early detection of very dilute smoke (e.g., clean rooms, HVAC ducts).
  • Class B: Early detection in critical spaces (e.g., electronic equipment rooms).
  • Class C: Standard detection for general areas equivalent to conventional point detectors.

• Test Procedures
  Comprehensive test fires including smouldering wood and cotton, flaming plastics, and n-heptane fires validate detector performance. Annexes provide detailed protocols for testing and fire sensitivity assessment.

• Design Tools & System Components
  Design tools, often software or tables, assist in determining detector sensitivity for specific sampling device configurations. Components of the sampling network, including pipes and sampling points, require verification as part of the system.

• Ancillary Device Integration
  ASDs may connect to remote indicators and control relays, with operational reliability requirements for such interfaces.

Applications

• Critical Infrastructure Protection
  Ideal for early fire detection in sensitive environments such as clean rooms, data centers, telecom facilities, and museums where very low levels of smoke need to be identified promptly.

• Commercial and Residential Buildings
  Provides reliable fire alarm integration for offices, hotels, apartments, and public buildings, enhancing occupant safety through prompt detection.

• Industrial Facilities
  Used in factories and warehouses to detect fires in processes generating smokes or dust, preventing catastrophic damage.

• Air Conditioning and Ventilation Systems
  Sampling pipes installed inside ducts enable rapid detection of smoke spreading through ventilation, mitigating systemic fire hazards.

Related Standards

• EN 54 Series for Fire Detection and Alarm Systems

  • Part 1: Introduction
  • Part 2: Control and Indicating Equipment
  • Part 4: Power Supply Equipment
  • Part 7: Point Smoke Detectors Using Scattered Light
  • Part 13: Compatibility Assessment
  • Part 14: Planning, Design, Installation, and Maintenance Guidelines
  • Part 27: Duct Smoke Detectors

• Electromagnetic and Environmental Testing Standards

  • EN 50130-4: Electromagnetic Compatibility for Fire Alarm Components
  • EN 60068 Series: Environmental Testing for Vibration, Shock, and Temperature Resilience

• Construction Products Regulation 305/2011
  Annex ZA of prEN 54-20 details the standard’s alignment with EU product construction regulatory requirements, ensuring safety and market compliance.

---

Compliance with prEN 54-20 supports the deployment of highly sensitive, reliable aspirating smoke detectors that enhance fire safety infrastructure, especially where early detection can save lives and reduce property damage. For professionals and stakeholders in fire protection, understanding this standard is key to designing, manufacturing, and installing optimum fire alarm solutions.

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2014
Sistemi za odkrivanje in javljanje požara ter alarmiranje - 20. del: Aspiracijski dimni
javljalniki
Fire detection and fire alarm systems - Part 20: Aspirating smoke detectors
Brandmeldeanlagen - Teil 20: Ansaugrauchmelder
Systèmes de détection et d'alarme incendie - Partie 20 : Détecteurs de fumée par
aspiration
Ta slovenski standard je istoveten z: prEN 54-20
ICS:
13.220.20 3RåDUQD]DãþLWD Fire protection
13.320 Alarmni in opozorilni sistemi Alarm and warning systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
DRAFT
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2014
ICS 13.220.20 Will supersede EN 54-20:2006
English Version
Fire detection and fire alarm systems - Part 20: Aspirating smoke
detectors
Systèmes de détection et d'alarme incendie - Partie 20 : Brandmeldeanlagen - Teil 20: Ansaugrauchmelder
Détecteurs de fumée par aspiration
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 72.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations which
stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other language
made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
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.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2014 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 54-20:2014 E
worldwide for CEN national Members.

Contents
Foreword . 3
1 Scope. 5
2 Normative references . 5
3 Terms, definitions and abbreviations . 6
4 Requirements . 7
5 Test and evaluation methods . 14
6 Assessment and verification of constancy of performance (AVCP) . 38
7 Classification . 46
8 Marking, labelling and packaging . 46
Annex A (informative) Apparatus for Response Value (RV) measurements . 47
Annex B (normative) Smouldering (pyrolysis) wood fire (TF2). 54
Annex C (normative) Reduced smouldering pyrolysis wood fires (TF2A and TF2B) . 57
Annex D (normative) Glowing smouldering cotton fire (TF3) . 60
Annex E (normative) Reduced glowing smouldering cotton fire (TF3A and TF3B) . 62
Annex F (normative) Flaming plastics (polyurethane) fire (TF4) . 65
Annex G (normative) Flaming liquid (n-heptane) fire (TF5) . 67
Annex H (normative) Reduced flaming liquid (n-heptane) fire (TF5A and TF5B) . 69
Annex I (normative) Fire test room and ventilation system . 72
Annex J (informative) Information concerning the requirements for the response to
slowly developing fires. 76
Annex K (informative) Apparatus for air flow monitoring test . 80
Annex L (informative) Method for fire sensitivity testing using an intermediate sampling
hole . 83
Annex M (normative) Data supplied with aspirating smoke detectors . 84
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive Construction Products Regulation 305/2011 . 85

Foreword
This document (prEN 54-20:2014) has been prepared by Technical Committee CEN/TC 72 “Fire
detection and fire alarm systems”, the secretariat of which is held by BSI.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 54–20:2006.
This document has been prepared under a mandate given to CEN by the European Commission and
the European Free Trade Association, and supports basic requirements of EU Regulation(s).
For relationship with EU Regulation(s), see informative Annex ZA, which is an integral part of this
document.
This edition incorporates the following main changes made with respect to the previous edition of
EN 54–20:2006 as follows:
1. correction of a typographical error in the Scope,
2. a major revision of Annex ZA and new clause on AVCP in line with other standards in the
EN 54 series,
3. modification of the structure of the standard to match the CEN template,
4. introduction of the concept of design tools including requirements and a process for assessing
them,
5. clarification of the assessment of components in the sampling device,
6. addition of an informative annex to describe a method for fire sensitivity testing using an
intermediate sampling hole,
7. clarification of air flow testing of ASDs which do not operate below 0 °C and for multi-port
ASD systems.
8. example tests for assessing the response to slowly developing fires are provided as opposed
on only allowing assessment by inspection of documentation.
9. a note has been added to 5.5.1.3.4 highlighting the importance of clean air.
EN 54 “Fire detection and fire alarm systems” consists of the following parts:
- Part 1: Introduction
- Part 2: Control and indicating equipment
- Part 3: Fire alarm devices – Sounders
- Part 4: Power supply equipment
- Part 5: Heat detectors - Point detectors
- Part 7: Smoke detectors - Point detectors using scattered light, transmitted light or ionization
- Part 10: Flame detectors - Point detectors
- Part 11: Manual call points
- Part 12: Smoke detectors - Line detectors using an optical light beam
- Part 13: Compatibility assessment of system components
- Part 14: Guidelines for planning, design, installation, commissioning, use and maintenance
- Part 15: Point detectors using a combination of detected fire phenomena
- Part 16: Voice alarm control and indicating equipment
- Part 17: Short-circuit isolators
- Part 18: Input/output devices
- Part 20: Aspirating smoke detectors
- Part 21: Alarm transmission and fault warning routing equipment
- Part 22: Line-type heat detectors
- Part 23: Fire alarm devices - Visual alarms
- Part 24: Components of voice alarm systems – Loudspeakers
- Part 25: Components using radio links and system requirements
- Part 26: Point fire detectors using carbon monoxide sensors
- Part 27: Duct smoke detectors
- Part 28: Non-resettable (digital) line type heat detectors
- Part 29: Multi-sensor fire detectors - Point detectors using a combination of smoke and heat
sensors
- Part 30: Multi-sensor fire detectors - Point detectors using a combination of carbon monoxide
and heat sensors
- Part 31: Multi-sensor detector – Point detector using
- Part 32: Guidelines for the planning, design, installation, commissioning, use and maintenance
of voice alarm systems
NOTE This list includes standards that are in preparation and other standards may be added. For current
status of published standards refer to www.cen.eu.
1 Scope
This European standard specifies the requirements, test methods and performance criteria for
aspirating smoke detectors for use in fire detection and fire alarm systems installed in or around
buildings or other civil engineering works.
This European standard provides for the assessment and verification of constancy of performance
(AVCP) of aspirating smoke detectors to this EN. Aspirating smoke detectors developed for the
protection of specific risks that incorporate special characteristics (including additional features or
enhanced functionality for which this standard does not define a test or assessment method) are also
covered by this standard. The performance requirements for any special characteristics are beyond
the scope of this standard.
NOTE Certain types of detector contain radioactive materials. The national requirements for radiation
protection differ from country to country and they are not therefore specified in this standard.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 54-1:2011, Fire detection and fire alarm systems – Part 1: Introduction
EN 54-2:1997, Fire detection and fire alarm systems – Part 2: Control and indicating equipment
including EN 54-2:1997/A1:2006
EN 54-4:1997, Fire detection and fire alarm systems – Part 4: Power supply equipment including
EN 54-4:1997/A1:2002 and EN 54-4:1997/A2:2006
EN 54-7:2000, Fire detection and fire alarm systems – Part 7: Smoke detectors – Point detectors
using scattered light, transmitted light or ionization including EN 54-7:2000/A1:2002, and
EN 54-7:2000/A2:2006
EN 50130-4:2011, Alarm systems – Part 4: Electromagnetic compatibility – Product family standard:
Immunity requirements for components of fire, intruder and social alarm systems
EN 60068-1:1994, Environmental testing – Part 1: General and guidance (IEC 60068 1:1988 +
Corrigendum 1988 + A1:1992)
EN 60068-2-1:2007, Environmental testing – Part 2: tests; tests A: cold (IEC 60068-2-1:2007)
EN 60068-2-2:2007, Environmental testing – Part 2-2: tests; tests B: dry heat (IEC 60068-2-2:2007)
EN 60068-2-6:2008, Environmental testing – Part 2 6: Tests – Tests Fc: Vibration (sinusoidal)
(IEC 60068-2-6:2007)
EN 60068-2-27:2009, Environmental testing – Part 2-27: Tests – Test Ea and guidance: Shock
(IEC 60068-2-27:2008)
EN 60068-2-42:2003, Environmental testing – Part 2-42: Tests; Test Kc: Sulfur dioxide test for
contacts and connections (IEC 60068-2-42:2003)
EN 60068-2-75:1997, Environmental testing – Part 2-75: Tests – Test Eh: Hammer tests
(IEC 60068-2-75:1997)
EN 60068-2-78:2001, Environmental testing – Part 2-78: Tests; Test Cab: Damp heat, steady state
(IEC 60068-2-78:2001)
EN 61386-1:2008, Conduit systems for electrical installations – Part 1: General requirements
(IEC 61386-1:2008)
3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 54-1:2011 and the following
apply.
3.1.1
aspirating smoke detector
smoke detector, in which air and aerosols are drawn through a sampling device and carried to one or
more smoke sensing elements by an integral aspirator
Note 1 to entry: Fan or pumps are examples of integral aspirators.
Note 2 to entry: Each smoke sensing element may contain more than one sensor exposed to the same
smoke sample.
3.1.2
design tool
means for determining the sensitivity class of any sampling device and detector configuration
Note 1 to entry: The design tool may be provided in a variety of forms e.g. as a software tool or a set of tables.
3.1.3
recovery
treatment of a specimen, after conditioning, so that the properties of the specimen may be stabilized
before measurement of the said property as required by this standard
3.1.4
response value
measure of the aerosol concentration in the proximity of the smoke sensing element at the moment
that the specimen generates an alarm signal
Note 1 to entry: In this document, there is a test method for response value in 5.1.5.
3.1.5
sampling device
component or series of components or dedicated device (e.g. a pipe network, dedicated duct, probe
or hood) which forms part of the ASD and transfers samples of air to the smoke sensing element(s)
Note 1 to entry: The sampling device may be supplied separately.
3.1.6
sampling point
any point at which an air sample is drawn into the sampling device
3.1.7
transport time
time for aerosols to transfer from a sampling point to the smoke sensing element
3.2 Abbreviations
For the purposes of this standard, the following abbreviations apply:
ASD Aspirating smoke detector
CIE Control and indicating equipment
CPC Condensation particle counter
DUT Detector under test
EEA European Economic Area
EMC Electromagnetic compatibility
EOT End of test
FPC Factory production control
MIC Measuring ionization chamber
RV Response value
4 Requirements
4.1 General
To conform to this standard the detector shall meet the requirements of this clause, which shall be
verified by inspection and engineering assessment, and when tested in accordance with the tests
described in Clause 5, shall meet the requirements of the tests.
4.2 Nominal activation conditions/sensitivity
4.2.1 Individual visual alarm indication
Each aspirating smoke detector shall be provided with (an) integral red visual indicator(s), visible from
outside the aspirating smoke detector, by which the individual smoke sensing element(s) (see 3.1.1),
which released an alarm, can be identified, until the alarm condition is reset. Where other conditions
of the detector may be visually indicated, they shall be clearly distinguishable from the alarm
indication.
4.2.2 Repeatability
The detector shall have stable behaviour with respect to its sensitivity after a number of alarm
conditions. When tested according to 5.2.2.2, test results shall meet the compliance criteria specified
in 5.2.2.3.
4.2.3 Reproducibility
The sensitivity of the detector shall not vary unduly from specimen to specimen. When tested
according to 5.2.3.2, test results shall meet the compliance criteria specified in 5.2.3.3.
4.2.4 Repeatability - Response to slowly developing fires
The provision of 'drift compensation' (e.g. to compensate for sensor drift due to the build up of dirt in
the detector), and/or the provision of algorithms to match the sensitivity of a detector to its
environment, shall not lead to a significant reduction in the detector's sensitivity to slowly developing
fires.
If such drift compensation is included, then it shall not lead to a significant change in the detector's
sensitivity to slowly developing fires when assessed as described in 5.2.4 and shall meet the
compliance criteria specified therein.
4.3 Operational reliability
4.3.1 Classification of sensitivity
The manufacturer shall clearly state, in the data presented in Clause 9 to which sensitivity class or
classes the aspirating smoke detector is designed. To demonstrate compliance with a specific
sensitivity class the aspirating smoke detector shall be subjected to appropriate fire sensitivity tests as
required in Table 1 and defined in 5.5.1. Various pipe and hole configurations shall be tested in order
to assess the design tool as specified in 5.3.1.
NOTE Due to the inherent flexibility in the design of sampling devices, aspirating smoke detectors are
generally intended for use in many varied and often rather specialized applications. Therefore it is not possible to
conduct type tests that define acceptance criteria for all of these applications. However, in recognition of the
diversity of application three sensitivity classes are defined to enable system designers and installers to select
the most appropriate sensitivity.
Table 1 provides a summary of the three sensitivity classes of detector and the corresponding fire
tests used for this classification of sensitivity.
Table 1 — Sensitivity classes for aspirating smoke detectors
Class Description Example application(s) Requirement
A Aspirating smoke detector Very early detection: the detection of Passes test fires
providing very high sensitivity very dilute smoke for example entering TF2A, TF3A, TF4
air conditioning ducts to detect the and TF5A
extremely dilute concentrations of
smoke that might emanate from
equipment in the environmentally
controlled area such as a clean room.
B Aspirating smoke detector Early detection: for example special Passes test fires
providing enhanced fire detection within or close to TF2B, TF3B, TF4
sensitivity particularly valuable, vulnerable or and TF5B
critical items such as computer or
electronic equipment cabinets.
C Aspirating smoke detector Standard detection: general fire Passes test fires
providing normal sensitivity detection in normal rooms or spaces, TF2, TF3, TF4
giving, for example, at least an and TF5
equivalent level of detection as a point
or beam type smoke detection system.

4.3.2 Connection of ancillary devices
The detector may provide for connections to ancillary devices (e.g. remote indicators, control relays).
Where such connections are present, the detector shall be assessed in accordance with 5.3.2 to
ensure that open or short circuit failure of such connections do not prevent correct operation of the
detector.
4.3.3 Manufacturer's adjustments
It shall not be possible to change the manufacturer's settings except by special means (e.g. the use of
a special code or tool) or by breaking or removing a seal. See 5.3.3 for evaluation method.
4.3.4 On site adjustment of response behaviour
NOTE 1 The effective response behaviour of an aspirating smoke detector is dependent upon both the
sensitivity settings of the smoke sensing element and the design of the sampling device. Many types of aspirating
smoke detectors therefore have facilities to adjust the smoke sensing element sensitivity to suit the application
and sampling device etc.
If there is provision for field-adjustment of the sensitivity of the smoke sensing element then:
a) access to the means of adjustment shall be limited by the need for the use of tools or a special
code;
b) it shall be possible to determine what sensitivity settings have been selected and to relate these
to documentation which describes the sensitivity settings required for different sampling
devices and applications;
NOTE 2 These adjustments may be made at the detector or at the control and indicating equipment.
NOTE 3 Changing sensitivity settings may affect the sensitivity class of the installed ASD – see Clause 7.
c) if it is possible to configure the detector (including the sampling device and the sensitivity
settings) in such a way that the detector does not conform to this standard, it shall be clearly
marked on the detector or in the associated data that, if such configurations are used, the
detector does not conform to this standard.
d) See 5.3.4 for evaluation method.
4.3.5 Mechanical strength of the pipework
Sampling pipes and fittings shall have adequate mechanical strength and temperature resistance.
Pipes shall either be classified in accordance with EN 61386-1:2008 to at least class 1131 (for the
significance of the digits, see Table 2) or shall be tested in accordance with 5.3.5.
Table 2 — Mechanical requirements of sampling pipe
Property Class Severity
Resistance to compression 1 125 N
Resistance to impact 1 0,5 kg, 100 mm height to fall
Temperature range 31 −15 °C to +60 °C

Where the supplier of the ASD does not supply pipes for the sampling device, the product
documentation shall specify that the requirements of this subclause shall be met.
4.3.6 Components in the sampling device
The use of components (box, filter, sensor, valve etc.) in the sampling device shall be described in the
documentation which shall be assessed in accordance with 5.3.6. The ASD, including any allowed
combination of components (in particular the worst case combination in accordance with the
manufacturer's documentation and/or design tool), shall meet the requirements of this standard.
If the component in the sampling device incorporates a sensing element which participates in the
signal output of the ASD (e.g. for localisation information) then the performance of the ASD, including
these sensing elements, shall meet the requirements of this standard.
It shall be possible to identify any optional component which is permitted for use on the ASD as
described in the manufacturer’s documentation (or design tool) which shall include information on the
effects of the components in terms of flow restriction and smoke attenuation and how these are
compensated to ensure compliance with EN 54-20 (e.g. shortening pipes, reducing the number of
holes or increasing detector sensitivity).
4.3.7 Airflow monitoring
4.3.7.1 Airflows outside operational limits
A fault signal shall be given when the airflow is outside the operational limits as specified by the
manufacturer in his data
This requirement shall be assessed as described in 5.3.7.
4.3.7.2 Monitoring of Airflow
The airflow through the aspirating smoke detector shall be monitored to detect leakage or obstruction
of the sampling device or sampling point(s).
Either a fault signal shall be given when any leakage or obstruction results in an increase or decrease
in the volumetric airflow of 20 % and greater through the aspirating smoke detector, or where the
aspirating smoke detector incorporates technology which provides for constant (or near constant)
volumetric flow rate, which is largely independent of the sampling device (e.g. incorporates speed
control of the fan or uses a positive displacement pump), then a fault signal shall be given when there
is a loss of 50 % and greater of sampling points.
In both cases a period of 300 s is allowed between the fault being applied and the fault signal being
given.
See 5.1.6 for evaluation method.
NOTE 1 This time is independent of any delay times between signalling the fault and its indication at the CIE
and is to allow for spurious short term flow variations which would otherwise result in unwanted fault signals.
NOTE 2 The 20% deviation in flow is applied to the volumetric flow through the whole detector. Where there
are multiple inlets to the detector (which may or may not have individual flow sensors) the flow should be reduced
evenly across all the ports. However, where there is a flow sensor in each inlet port, the manufacture and the
testing authority may agree to test using a 20 % deviation on one port only. For further details see Annex K.
4.3.7.3 Memorizing the 'normal' flow
Where an aspirating smoke detector has a facility to memorize the 'normal' flow (present when the
detector is installed or serviced) and thereafter monitor for deviations from this normal flow, the action
of setting the memorized 'normal' flow and the fault thresholds shall be a voluntary action under level
3 access (as defined in EN 54-2).
Power cycling the aspirating smoke detector (turning it off and on) shall not result in a change to the
memorized normal flow.
These requirements shall be assessed as described in 5.3.7.
NOTE The implication of this clause is that automatic adjustment of the memorized normal flow and
subsequent monitoring for deviations is not allowed.
4.3.8 Power supply
The power for the aspirating detector shall be supplied by a power supply conforming to EN 54–4.
NOTE This power supply may be common to the control and indicating equipment, be incorporated into the
ASD or be provided as a separate unit.
4.3.9 Software controlled detectors
4.3.9.1 General
For detectors that rely on software control to fulfil the requirements of this standard, the requirements
of 4.3.9.2, 4.3.9.3 and 4.3.9.4 when assessed as specified in 5.3.9 shall be met.
4.3.9.2 Software documentation
4.3.9.2.1 The manufacturer shall submit documentation to the testing authority which gives an
overview of the software design. This documentation shall be in sufficient detail for the design to be
inspected for compliance with this standard and shall include at least the following:
a) functional description of the main program flow (e.g. as a flow diagram or structogram) including:
1) brief description of the modules and the functions that they perform,
2) way in which the modules interact,
3) overall hierarchy of the program,
4) way in which the software interacts with the hardware of the detector,
5) way in which the modules are called, including any interrupt processing;
b) description of which areas of memory are used for the various purposes (e.g. the program, site
specific data and running data);
c) designation, by which the software and its version can be uniquely identified.
4.3.9.2.2 The manufacturer shall also have available detailed design documentation, which only
needs to be provided if required by the testing authority. It shall comprise at least the following:
a) overview of the whole system configuration, including all software and hardware components;
b) description of each module of the program, containing at least:
1) name of the module,
2) description of the tasks performed,
3) description of the interfaces, including the type of data transfer, the valid data range and the
checking for valid data;
c) full source code listings, as hard copy or in machine-readable form (e.g. ASCII-code), including
global and local variables, constants and labels used, and sufficient comment for the program
flow to be recognized;
d) details of any software tools used in the design and implementation phase (e.g. CASE-Tools,
Compilers).
4.3.9.3 Software design
To ensure the reliability of the detector, the following requirements for software design shall apply:
a) software shall have a modular structure,
b) design of the interfaces for manually and automatically generated data shall not permit invalid
data to cause error in the program operation,
c) software shall be designed to avoid the occurrence of deadlock of the program flow.
4.3.9.4 The storage of programs and data
The program necessary to conform to this European standard and any pre-set data, such as
manufacturer's settings, shall be held in non-volatile memory. Writing to areas of memory containing
this program and data shall only be possible by the use of some special tool or code and shall not be
possible during normal operation of the detector.
Site-specific data shall be held in memory which will retain data for at least two weeks without
external power to the detector, unless provision is made for the automatic renewal of such data,
following loss of power, within 1 h of power being restored.
4.4 Tolerance to supply voltage
4.4.1 Variation in supply parameters
Within the specified range(s) of the supply parameters, the sensitivity of the detector shall not be
unduly dependent on these parameters (e.g. voltage). To confirm this, the detector shall be tested as
specified in 5.4.1.
4.5 Performance parameters under fire conditions
4.5.1 Fire sensitivity
The detector shall have adequate sensitivity to incipient type fires that may occur in buildings. To
confirm this, the detector shall be tested as specified in 5.5.1.
4.6 Durability of nominal activation conditions/sensitivity and operational reliability
4.6.1 Temperature resistance
4.6.1.1 Dry heat (operational)
The detector shall function correctly at high ambient temperatures when tested according to 5.6.1.1.
4.6.1.2 Cold (operational)
The detector shall function correctly at low ambient temperatures when tested according to 5.6.1.2.
Where the detector cannot operate below 0 °C:
a) the manufacturer's information shall clearly state that the detector will not operate below 0 °C and
that special precautions have to be taken against the temperature falling below 0 °C.
b) the detector shall generate an appropriate fault warning which shall be tested as specified in
5.6.1.2.4.
4.6.2 Humidity resistance
4.6.2.1 Damp heat, steady state (operational)
The detector shall function correctly at high relative humidity (without condensation) when tested
according to 5.6.2.1.
4.6.2.2 Damp heat, steady state (endurance)
The detector shall be capable of withstanding long-term exposure to a high level of continuous
humidity when tested according to 5.6.2.2.
4.6.3 Corrosion resistance
4.6.3.1 SO corrosion (endurance)
The detector shall function correctly when submitted to the corrosive effects of Sulfur Dioxide when
tested according to 5.6.3.1.
4.6.4 Shock and vibration resistance
4.6.4.1 Shock (operational)
The detector shall function correctly when submitted to mechanical shocks which are likely to occur in
the service environment when tested according to 5.6.4.1.
4.6.4.2 Impact (operational)
The detector shall function correctly when submitted to mechanical impacts which it may sustain in
the normal service environment when tested according to 5.6.4.2.
4.6.4.3 Vibration, sinusoidal (operational)
The detector shall function correctly when submitted to vibration at levels appropriate to its normal
service environment when tested according to 5.6.4.3.
4.6.4.4 Vibration, sinusoidal (endurance)
The detector shall be capable of withstanding long exposure to vibration at levels appropriate to the
service environment when tested according to 5.6.4.4.
4.6.5 Electrical stability
4.6.5.1 EMC, immunity (operational)
The detector shall operate shall operate correctly when submitted to electromagnetic interference
when tested according to 5.6.5.1.
5 Test and evaluation methods
5.1 General
5.1.1 Atmospheric conditions for tests
Unless otherwise stated in a test procedure, the testing shall be carried out after the test specimen
has been allowed to stabilize in the standard atmospheric conditions for testing as described in
EN 60068-1:1994 as follows:
a) temperature : (15 to 35) °C;
b) relative humidity : (25 to 75) %;
c) air pressure : (86 to 106) kPa.
If variations in these parameters have a significant effect on a measurement, then such variations
shall be kept to a minimum during a series of measurements carried out as part of one test on one
specimen.
5.1.2 Operating conditions for tests
If a test method requires a specimen to be operational, then the specimen shall be connected to
supply and monitoring equipment with characteristics as required by the manufacturer's data. Unless
otherwise specified in the test method, the supply parameters applied to the specimen shall be set
within the manufacturer's specified range(s) and shall remain substantially constant throughout the
tests. The value chosen for each parameter shall normally be the nominal value, or the mean of the
specified range.
Where an aspirating smoke detector has multiple sensitivity settings, the sensitivity of the DUT during
all tests in Table 3 (with the exception of the fire sensitivity test in 5.5.1) shall be set at the highest
sensitivity setting used during the fire sensitivity test(s).
NOTE It is not intended that the environmental tests are conducted at all possible sensitivity settings, only at
the highest used during the fire sensitivity test. This is particularly relevant where multiple sensitivity classes
and/or multiple configurations are submitted.
To allow the flow monitoring function to be checked as required before, during and/or after
environmental tests, the sampling device may be simulated by a simpler sampling device (e.g. stub
pipe with appropriate orifice(s)) to providing a typical airflow through the detector.
During the dry heat, damp heat and cold tests, a sufficient length of pipe shall be installed in the
chamber to allow the temperature of the test aerosol entering the DUT to stabilize at the test
temperature.
The details of the supply and monitoring equipment and the alarm criteria used shall be given in the
test report.
5.1.3 Mounting arrangements
When necessary, the specimen shall be mounted by its normal means of attachment in accordance
with the manufacturer's instructions. If these instructions describe more than one method of mounting
then the method considered to be most unfavourable shall be chosen for each test.
5.1.4 Tolerances
Unless otherwise stated, the tolerances for the environmental test parameters shall be as given in the
basic reference standards for the test (i.e. the relevant Parts of EN 60068-2 as listed in Clause 2).
If a specific tolerance or limit is not specified in a requirement or test procedure, then deviation limits
of ± 5 % shall be applied.
5.1.5 Measurement of response value
5.1.5.1 General
Because there are a number of different types of aspirating detectors available operating on quite
different principles, which have very different ranges of sensitivity, various methods can be used to
measure the response value. The object of any method chosen shall be to determine a measure of
the aerosol concentration, which when passing through the detector, just causes an alarm to be
raised. This can generally be achieved by introducing smoke or an aerosol into the sampled air
stream so that the detector is subjected to a slowly increasing concentration, and recording the
concentration at the moment when an alarm is generated. Because the response value is only used
as a relative measurement, various parameters to measure the aerosol concentration may be used,
providing that the chosen parameter is essentially proportional to the particle number concentration,
for the particular test aerosol. For further information it is recommended to refer to Annex A.
5.1.5.2 Typical RV measurement procedure
The specimen for which the response value is to be measured shall be connected to measuring
apparatus as recommended in Annex A. The airflow through the detector shall be controlled to a
typical rate within the manufacturer's specification.
The DUT shall be connected to its supply and monitoring equipment as described in 5.1.2 and shall
be allowed to stabilize for a period of at least 15 min unless otherwise specified by the manufacturer.
Before commencing each measurement the measuring apparatus and DUT shall be purged
sufficiently to ensure that the new results are not affected by the previous measurement.
The aerosol concentration shall then be increased at an appropriate rate, depending upon the
detector's sensitivity. The rate of increase in aerosol density shall be similar for all measurements on
a particular detector type. It is recommended that the alarm signal is generated between 2 min and
10 min after the start of the measurement. Preliminary testing may be necessary to determine the
appropriate rate for a particular detector type.
The response value N shall be taken as the aerosol concentration at the moment when the detector
gives the alarm signal. The particular measuring unit for the aerosol concentration depends on the
measuring apparatus employed.
5.1.6 Test of air flow monitoring facility
In accordance with the requirement in 4.3.7.2, when testing of the air flow monitoring facility is
required it shall be tested as follows:
a) where the volumetric flow is not maintained constant, the increase and decrease in flow shall be
verified as follows:
b) the normal volumetric airflow (e.g. litres/min) (Fn) shall be determined from the sampling
configuration used for the fire tests using suitable instrumentation;
NOTE Where multiple configurations are tested in the fire test room (for example where the detector is multi
class) then Fn shall be between the maximum and minimum flow rates of the configuration.
c) the DUT shall be set up at a Test flow rate (Ft = Fn+/-10 %) for testing the airflow monitoring.
Where the DUT has multiple (n) input ports the flow shall be equally split across the ports
d)
e) for a DUT that has a memorized normal flow the Ft shall be entered to the memory in accordance
with the normal operating instructions for the DUT. This shall only be done once at the start of
each environmental test and shall not be done during or after conditioning;
f) for decreased flow the volumetric airflow is decreased from Ft by 20 % (Ft-20 %);
g) for increased flow the volumetric airflow is increased from Ft by 20 % (Ft+20 %).
1) An example of a possible practical arrangement to achieve this test is given in Annex K.
2) Where the tests of a) cannot be applied (e.g. where the volumetric flow is maintained
constant), the flow monitoring facility is to be verified by the loss of maximum of the 50 % of
sampling points. The sampling points lost shall be those furthest from the sensing element
on the worst case sampling device used in the fire sensitivity test(s). Loss of the points shall
be separately tested for:
i) total blockage of 50 % of the sampling points furthest from the sensing element; and
ii) breakage of the sampling device such that the same points are lost by breakage.
5.1.7 Provision for tests
Eight specimen aspirating detectors (or at least a sufficient number of specimens to allow the
reproducibility test to include eight smoke and flow sensitive parts (see Table 3 notes) are required to
conduct the tests as indicated in the following test schedule, along with sufficient sampling pipes and
fittings to set up the various sampling device configuration required by the tests.
The specimens submitted shall be representative of the manufacturer's normal production with regard
to their construction and calibration.
NOTE This implies that the mean response value of the eight specimens, found in the reproducibility test,
should also represent the production mean, and that the limits specified in the reproducibility test should also be
applicable to the manufacturer's production.
5.1.8 Test schedule
The specimens shall be tested according to the test schedule in Table 3. The specimens shall be
numbered arbitrarily (with the exception of No. 8).
Table 3 — Test schedule
a
Test Clause Specimen No(s)
Repeatability 5.2.2 1
b, c
Reproducibility 5.2.3 1 to 8
Variation of supply voltage 5.4.1 1
Dry heat (operational) 5.6.1.1 1
Cold (operational) 5.6.1.2 1
Damp heat, Steady State (operational) 5.6.1.2 1
Damp heat, Steady State (endurance) 5.6.2.2 2
SO corrosion (endurance) 5.6.3.1 3
Shock (operational) 5.6.4.1 4
Impact (operational) 5.6.4.2 4
Vibration sinusoidal (operational) 5.6.4.3 5
Vibration sinusoidal (endurance) 5.6.4.4 5
EMC, immunity (operational) 5.6.5.1 6 and 7
Fire sensitivity 5.5.1 8
a
The schedule shows the specimen numbers recommended for each test. Other arrangements
may be used to improve the efficiency or cost of testing, or to reduce the number of specimens
damaged by the testing. However, the reproducibility of the sensitivity of at least eight smoke
sensitive parts shall be measured in the reproducibility test. If fewer specimens are to be used for
the rest of the tests then the possible damaging effects of subjecting a specimen to a number of
tests, especially endurance tests, have to be considered.
b
The least sensitive specimen shall be designated specimen No 8 and used in the fire sensitivity
tests.
c
In the interests of test economy, it is permitted to use the same specimen for more than one
environmental test. Furthermore, for EMC or the mechanical environmental tests, intermediate
functional test(s) on the specimen(s) used for more than one test may be omitted, and the RV and
full flow monitoring tests conducted at the end of the sequence of tests only. However it should be
noted that in the event of a failure, it may not be possible to identify which test exposure caused the
failure so a simple function test of smoke and flow between each test exposure is advisable.

5.2 Nominal activation conditions/sensitivity
5.2.1 Individual visual alarm indication
The visual alarm indication(s) shall each be inspected to be in accordance with the requirements of
4.2.1. Each indicator shall be activated independently, and confirmed to correctly indicate the smoke
sensing element which released the alarm.
5.2.2 Repeatability
5.2.2.1 Object
To show that the detector has stable behaviour with respect to its sensitivity even after a number of
alarm conditions.
5.2.2.2 Test procedure
The response value of the specimen to be tested shall be measured six times as described in 5.1.5.
The maximum and minimum of these six response values shall be designated N and N
max min
respectively.
5.2.2.3 Requirements
The ratio of the response values N : N shall not be greater than 1.6.
max min
5.2.3 Reproducibility
5.2.3.1 Object
To show that the sensitivity of the detector does not vary unduly from specimen to specimen.
5.2.3.2 Test procedure
The function of the airflow monitoring facility shall be checked, on each specimen, as described in
5.1.6.
The response value of each of the test specimens shall be measured as described in 5.1.5.
The mean of these eight response values shall be calculated and shall be designated N
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