EN 54-20 Fire detection and fire alarm systems – Part 20: Aspirating smoke detectors
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 buildings.
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 not 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 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.
EN 54-1:1996, Fire detection and fire alarm systems – Part 1: Introduction
EN 54-2, Fire detection and fire alarm systems – Part 2: Control and indicating equipment
EN 54-4, Fire detection and fire alarm systems – Part 4: Power supply equipment
EN 54-7:2000, Fire detection and fire alarm systems – Part 7: Smoke detectors – Point detectors using scattered light, transmitted light or ionization
EN 50130-4:1995, Alarm systems – Part 4: Electromagnetic compatibility – Product family standard: Immunity requirements for components of fire, intruder and social alarm systems
EN 60068-1, Environmental testing – Part 1: General and guidance (IEC 60068-1:1988 + Corrigendum 1988 + A1:1992)
EN 60068-2-1, Environmental testing; part 2: tests; tests A: cold (IEC 60068-2-1:1990)
EN 60068-2-2, Basic environmental testing procedures; part 2: tests; tests B: dry heat (IEC 60068-2¬2:1974 + IEC 60068-2-2A:1976)
EN 60068-2-6, Environmental testing – Part 2: Tests – Tests Fc: Vibration (sinusoidal) (IEC 60068-2¬6:1995 + Corrigendum 1995)
EN 60068-2-27, Basic environmental testing procedures – Part 2: Tests – Test Ea and guidance: Shock (IEC 60068-2-27:1987)
EN 60068-2-42, Environmental testing – Part 2-42: Tests; Test Kc: Sulphur dioxide test for contacts and connections (IEC 60068-2-42:2003)
EN 60068-2-75, Environmental testing – Part 2: Tests – Test Eh: Hammer tests (IEC 60068-2-75:1997)
EN 60068-2-78, Environmental testing – Part 2-78: Tests; Test Cab: Damp heat, steady state (IEC 60068-2-78:2001)
EN 61386-1:2004, Conduit systems for electrical installations – Part 1: General requirements (IEC 61386-1:1996 + A1:2000)
3 Terms and definitions
For the purposes of this document the terms and definitions given in EN 54-1:1996 and the following apply.
3.1
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 (e.g. fan or pump)
NOTE Each smoke sensing element may contain more than one sensor exposed to the same smoke sample.
3.2
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 The sampling device may be supplied separately.
3.3
sampling point
any point at which an air sample is drawn into the sampling device
3.4
response threshold value (RTV)
measure of the aerosol concentration in the proximity of the smoke sensing element at the moment that the specimen generates an alarm signal, when it is tested as described in 6.1.5
3.5
transport time
time for aerosols to transfer from a sampling point to the smoke sensing element
3.6
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
4 Symbols and abbreviations
For the purposes of this standard, the following abbreviations apply:
5 Requirements
5.1 Compliance
To comply with 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 6, shall meet the requirements of the tests.
5.2 Individual visual alarm indication
Each aspirating smoke detector shall be provided with integral red visual indicator(s), visible from outside the aspirating smoke detector, by which the individual smoke sensing element(s) (see 3.1), 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.
5.3 Connection of ancillary devices
The detector may provide for connections to ancillary devices (e.g. remote indicators, control relays), but open- or short-circuit failures of these connections shall not prevent the correct operation of the detector.
5.4 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.
5.5 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 classification 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 comply with 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 comply with this standard.
5.6 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 a detector to its environment, shall not lead to a significant reduction in the detector’s sensitivity to slowly developing fires.
Because it is not practical to make tests with very slow increases in smoke density, an assessment of the detector’s response to slow increases in smoke density shall be made by analysis of the circuit/software, and/or physical tests and simulations.
Where such algorithms are used, the detector shall be deemed to meet the requirements of this sub- clause if the documentation and assessment shows:
a) how and why a sensor drifts,
b) how the compensation technique modifies the detector response to compensate for the drift,
c) that suitable limits to the compensation are in place to prevent the algorithms/means being applied outside the known limitations of the sensor and to ensure ongoing compliance with the clauses of this standard,
d) for any rate of increase in smoke density R, which is greater than A/4 per hour (where A is the detector’s initial uncompensated response threshold value), the time for the detector to give an alarm does not exceed 1,6 x A/R by more than 100 s,
e) the range of compensation is limited such that, throughout this range, the compensation does not cause the response threshold value of the detector to exceed its initial value by a factor greater than 1,6.
NOTE Further information about the assessment of requirements d) and e) is given in Annex J.
5.7 Mechanical strength of the pipework
The sampling pipes and fittings shall have adequate mechanical strength and temperature resistance. The minimum requirement shall be:
To use pipes classified in accordance with EN 61386-1 to at least Class 1131 (for the first four digits, see Table 1).
5.8 Hardware components and additional sensing elements in the sampling device
Components, including optional components (box, filter, sensor, valve etc.) in the sampling device shall be described in the documentation. The ASD, including the hardware components listed (i.e. the worst case combination in accordance with the manufacturer’s documentation), shall meet the requirements of this standard.
If the component 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.
5.9 Airflow monitoring
5.9.1 A fault signal shall be given when the airflow is outside the operational limits as specified by the manufacturer in his data.
5.9.2 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.
5.9.3 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 shall be a voluntary action under level 3 access (as defined in EN 54-2).
5.9.4 Power cycling the aspirating smoke detector (turning it off and on) shall not result in a change to the memorized normal flow.
5.10 Power supply
5.11 Data
Aspirating smoke detectors shall either be supplied with sufficient technical, installation and maintenance data to enable their correct installation, sensitivity setting and operation or, if all of these data are not supplied with each ASD then reference to the appropriate data sheet(s) shall be given on, or with, each aspirating smoke detector.
The manufacturer shall declare in these data the classification of each sampling device configuration and associated sensitivity settings. If the number of configurations is undetermined, the manufacturer shall provide the necessary means to determine the classification of any used configuration.
These data shall be referred to in the test report to describe and determine the ‘worst case’ configuration(s) to be used in the fire tests (see 6.15) and the transport time for the sampling point(s) in the fire test room.
5.12 Additional requirements for software controlled detectors
5.12.1 General
For detectors that rely on software control to fulfil the requirements of this standard, the requirements of 5.12.2, 5.12.3 and 5.12.4 shall be met.
5.12.2 Software documentation
5.12.2.1 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:
5.12.2.2 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:
5.12.3 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. 5.12.4 The storage of programs and data
The program necessary to comply with 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.
6 Tests 6.1 General
6.1.1 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 as follows:
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.
6.1.2 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 6.15) shall be set at the highest sensitivity setting used during the fire sensitivity test(s).
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.
6.1.3 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.
6.1.4 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.
6.1.5 Measurement of response threshold value
6.1.5.1 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 threshold 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 threshold 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.
6.1.5.2 Typical RTV measurement procedure
The specimen for which the response threshold 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 6.1.2 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 threshold 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.
6.1.6 Test of the airflow monitoring facility
In accordance with the requirement in 5.9.2, 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:
1) the normal volumetric airflow (e.g. litres/min) (Fn) shall be determined from the sampling configuration used for the fire tests using suitable instrumentation;
2) the DUT shall be set up at a Test flow rate (Ft = Fn+/-10%) for testing the airflow monitoring. For a DUT that has a memorised 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;
3) for decreased flow the volumetric airflow is decreased from Ft by 20 % (Ft-20%);
4) for increased flow the volumetric airflow is increased from Ft by 20 % (Ft+20%); An example of a possible practical arrangement to achieve this test is given in Annex K.
b) 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:
1) total blockage of 50 % of the sampling points furthest from the sensing element; and
2) breakage of the sampling device such that the same points are lost by breakage.
6.1.7 Provision for tests
Eight specimen aspirating detectors (or at least sufficient specimens to allow the reproducibility test to include eight smoke sensitive parts (see Table 3 notes) are required to conduct the tests as indicated in the test schedule, see 6.1.8, along with sufficient sampling pipes and fittings to set up the various
6.2 Repeatability
6.2.1 Object
To show that the detector has stable behaviour with respect to its sensitivity even after a number of alarm conditions.
6.2.2 Test procedure
The response threshold value of the specimen to be tested shall be measured six times as described in 6.1.5.
The maximum and minimum of these six response threshold values shall be designated Nmax and Nmin respectively.
6.2.3 Requirements
The ratio of the response threshold values Nmax : Nmin shall not be greater than 1,6.
6.3 Reproducibility
6.3.1 Object
To show that the sensitivity of the detector does not vary unduly from specimen to specimen.
6.3.2 Test procedure
The function of the airflow monitoring facility shall be checked, on each specimen, as described in 6.1.6.
The response threshold value of each of the test specimens shall be measured as described in 6.1.5.
The mean of these eight response threshold values shall be calculated and shall be designated Nmean.
The maximum and minimum of these eight response threshold values shall be designated Nmax and Nmin respectively.
6.3.3 Requirements
The correct fault signals, in accordance with 5.9, shall be given during the checks of the airflow monitoring facility.
The ratio of the response threshold values Nmax : Nmean shall not be greater than 1,33. The ratio of the response threshold values Nmean : Nmin shall not be greater than 1,5.
6.4 Variation in supply parameters
6.4.1 Object
To show that within the specified range(s) of the supply parameters, (e.g. voltage), the sensitivity of the detector is not unduly dependent on these parameters.
This is either demonstrated by testing according to 6.4.2.1 or may be demonstrated by consideration of the electronic design of ASD and appropriate testing in accordance with 6.4.3.
6.4.2 Standard test procedure
6.4.2.1 Test procedure
The response threshold value of the specimen to be tested shall be measured as described in 6.1.5, and the function of the airflow monitoring facility shall be checked, as described in 6.1.6, under the nominal and extremes of the specified supply conditions (e.g. nominal, maximum and minimum supply voltage).
The maximum and minimum of the three response threshold values shall be designated Nmax and Nmin respectively.
6.4.2.2 Requirements
The correct fault signals, in accordance with 5.9, shall be given during the checks of the airflow monitoring facility.
The ratio of the response threshold values Nmax : Nmin shall not be greater than 1,6.
6.4.3 Alternative test procedure
:Where it can be shown by design examination that the sensitivity of the detector and speed of the airflow are independent of the supply voltage, then appropriate measurements (e.g. of internal voltages and flow rate) may be used to demonstrate that the detector meets this requirement.
-6.5 Dry heat (operational)
6.5.1 Object
To demonstrate the ability of the detector to function correctly at high ambient temperature, that may occur for short periods in the service environment.
6.5.2 Test procedure
6.5.2.1 Reference
The test apparatus and procedure shall be as described in EN 60068-2-2, Test Bb, and as described in 6.5.2.2 to 6.5.2.7.
6.5.2.2 Initial measurements
Before conditioning, the response threshold value shall be measured as described in 6.1.5, with the temperature stabilising pipes installed as required in 6.5.2.5.
6.5.2.3 State of the specimen during conditioning
The specimen shall be mounted as described in 6.1.3 and shall be connected to its supply and monitoring equipment as described in 6.1.2.
6.5.2.4 Conditioning
The following conditioning shall be applied:
6.5.2.5 Measurements during conditioning
The specimen shall be monitored during the transition to the conditioning temperature and during the conditioning period to detect any alarm or fault signals.
During the last hour of the conditioning period, the function of the airflow monitoring facility shall be checked as described in 6.1.6 and the response threshold value shall be measured as described in 6.1.5. For the RTV measurement, a sufficient length of pipe shall be installed in the chamber to allow the temperature of the test aerosol to stabilize at the test temperature before entering the detector.
It may also be necessary to have a length of pipe external to the chamber to transport the test aerosol from its source (e.g. a standard smoke tunnel). In this case the reference detector referred to in Figure A.4 is likely to be needed.
6.5.2.6 Final measurements
After a recovery period of at least 1 h at laboratory conditions, the function of the airflow monitoring facility shall be checked as described in 6.1.6 and the response threshold value shall be measured as described in 6.1.5.
6.5.2.7 Designation of measurements
The maximum and minimum of the three response threshold values measured in this test (i.e. before, during and after) shall be designated Nmax and Nmin respectively.
6.5.3 Requirements
No alarm or fault signals shall be given during the period that the temperature is increasing to the conditioning temperature or during the conditioning period, except as required by the tests in the last hour.
The correct fault signals, in accordance with 5.9, shall be given during the checks of the airflow monitoring facility.
The ratio of the response threshold values Nmax: Nmin shall not be greater than 1,6. 6.6 Cold (operational)
6.6.1 Object
To demonstrate the ability of the detector to function correctly at low ambient temperatures appropriate to the anticipated service environment.
6.6.2 Test procedure
6.6.2.1 Reference
The test apparatus and procedure shall be as described in EN 60068-2-1, Test Ab and as described in 6.6.2.2 to 6.6.2.6.
6.6.2.2 Initial measurements
Before conditioning, the response threshold value shall be measured as described in 6.1.5, with the temperature stabilising pipes installed as required in 6.5.2.5.
6.6.2.3 State of the specimen during conditioning
The specimen shall be mounted as described in 6.1.3 and shall be connected to its supply and monitoring equipment as described in 6.1.2.
6.6.2.4 Conditioning
The following conditioning shall be applied:
Temperature: (-10 ± 3) °C, Duration: 16 h.
If the detector cannot operate at less than 0 °C, then:
6.6.2.5 Measurements during conditioning
The specimen shall be monitored during transition to the conditioning temperature and during the conditioning period to detect any alarm or fault signals.
During the last hour of the conditioning period, the function of the airflow monitoring facility shall be checked as described in 6.1.6 and the response threshold value shall be measured as described in 6.1.5. For the RTV measurement, a sufficient length of pipe shall be installed in the chamber to allow the temperature of the test aerosol to stabilize at the test temperature before entering the detector.
6.6.2.6 Final measurements
After a recovery period of at least 1 h at laboratory conditions, the function of the airflow monitoring facility shall be checked as described in 6.1.6 and the response threshold value shall be measured as described in 6.1.5.
The maximum and minimum of the response threshold values measured in this test shall be designated Nmax and Nmin respectively.
6.6.3 Requirements
No alarm or fault signals shall be given during the period in which the temperature is decreasing to the conditioning temperature or during the conditioning period, except as required by the tests in the last hour.
The correct fault signals, in accordance with 5.9, shall be given during the checks of the airflow monitoring facility.
The ratio of the response threshold values Nmax : Nmin shall not be greater than 1,6. 6.7 Damp heat, steady state (operational)
6.7.1 Object
To demonstrate the ability of the detector to function correctly at high relative humidity (without condensation), which may occur for short periods in the anticipated service environment.
6.7.2 Test procedure
6.7.2.1 Reference
The test apparatus and procedure shall be as described in EN 60068-2-78, Test Cab and as described in 6.7.2.2 to 6.7.2.6.
6.7.2.2 Initial measurements
Before conditioning, the response threshold value shall be measured as described in 6.1.5, with the temperature stabilising pipes installed as required in 6.7.2.5.
6.7.2.3 State of the specimen during conditioning
The specimen shall be mounted as described in 6.1.3 and shall be connected to its supply and monitoring equipment as described in 6.1.2.
6.7.2.5 Measurements during conditioning
The specimen shall be monitored during the transition to the conditioning temperature and during the conditioning period to detect any alarm or fault signals.
During the last hour of the conditioning period, the function of the airflow monitoring facility shall be checked as described in 6.1.6 and the response threshold value shall be measured as described in 6.1.5. For the RTV measurement, a sufficient length of pipe shall be installed in the chamber to allow the temperature of the test aerosol to stabilize at the test temperature before entering the detector.
NOTE For practical reasons, it is accepted that the test aerosol will not be at the same relative humidity as the conditioning environment.
6.7.2.6 Final measurements
After a recovery period of at least 1 h at laboratory conditions, the function of the airflow monitoring facility shall be checked as described in 6.1.6 and the response threshold value shall be measured as described in 6.1.5.
The maximum and minimum of the response threshold values measured in this test shall be designated Nmax and Nmin respectively.
6.7.3 Requirements
No alarm or fault signals shall be given during the period that the temperature is increasing to the conditioning temperature or during the conditioning period, except as required by the tests in the last hour.
The correct fault signals, in accordance with 5.9, shall be given during the checks of the airflow monitoring facility.
The ratio of the response threshold values Nmax : Nmin shall not be greater than 1,6. 6.8 Damp heat, steady state (endurance)
6.8.1 Object
To demonstrate the ability of the detector to withstand the long term effects of humidity in the service environment (e.g. changes in electrical properties of materials, chemical reactions involving moisture, galvanic corrosion).
6.8.2 Test procedure 6.8.2.1 Reference
6.7.2.4 Conditioning
The following conditioning shall be applied:
The test apparatus and procedure shall be as described in EN 60068-2-78, Test Cab , and as described in 6.8.2.2 to 6.8.2.5.
6.8.2.2 Initial measurements
Before conditioning, the response threshold value shall be measured as described in 6.1.5.
6.8.2.3 State of the specimen during conditioning
The specimen shall be mounted as described in 6.1.3 but shall not be supplied with power during the conditioning.
6.8.2.4 Conditioning
The following conditioning shall be applied:
Temperature: (40 ± 2) °C,
Relative humidity: (93 ± 3) %, Duration: 21 days.
6.8.2.5 Final measurements
After a recovery period of at least 1 h at laboratory conditions, the function of the airflow monitoring facility shall be checked as described in 6.1.6 and the response threshold value shall be measured as described in 6.1.5.
The maximum and minimum of the response threshold values measured in this test shall be designated Nmax and Nmin respectively.
6.8.3 Requirements
The correct fault signals, in accordance with 5.9, shall be given during the checks of the airflow monitoring facility.
The ratio of the response threshold values Nmax : Nmin shall not be greater than 1,6. 6.9 Sulfer dioxide (SO2) corrosion (endurance)
6.9.1 Object
To demonstrate the ability of the detector to withstand the corrosive effects of sulfer dioxide as an atmospheric pollutant.
6.9.2 Test procedure
6.9.2.1 Reference
The test apparatus and procedure shall be as described in EN 60068-2-42, Test Kc, except that the conditioning shall be as described in 6.9.2.4.
6.9.2.2 Initial measurements
Before conditioning, the response threshold value shall be measured as described in 6.1.5.
6.9.2.3 State of the specimen during conditioning
The specimen shall be mounted as described in 6.1.3. It shall not be supplied with power during the conditioning, but it may have untinned copper wires, of the appropriate diameter, connected to sufficient terminals, to allow the final measurement to be made, without making further connections to the specimen.
Immediately after the conditioning, the specimen shall be subjected to a drying period of 16 h at (40 ± 2) °C, < 50 % RH, followed by a recovery period of at least 1 h at laboratory conditions. After this recovery period the function of the airflow monitoring facility shall be checked as described in 6.1.6, and the response threshold value shall be measured as described in 6.1.5.
The maximum and minimum of the response threshold values measured in this test shall be designated Nmax and Nmin respectively.
6.9.3 Requirements
The correct fault signals, in accordance with 5.9, shall be given during the checks of the airflow monitoring facility.
The ratio of the response threshold values Nmax : Nmin shall not be greater than 1,6. 6.10 Shock (operational)
6.10.1 Object
To demonstrate the immunity of the detector to mechanical shocks, which are likely to occur, albeit infrequently, in the anticipated service environment.
6.10.2.4 Conditioning
The specimen shall be monitored during the conditioning period to detect any alarm or fault signals.
6.10.2.6 Final measurements
After the conditioning, the function of the airflow monitoring facility shall be checked as described in 6.1.6 and the response threshold value shall be measured as described in 6.1.5.
The maximum and minimum of the response threshold values measured in this test shall be designated Nmax and Nmin respectively.
6.10.3 Requirements
No alarm or fault signals shall be given during the conditioning.
The correct fault signals, in accordance with 5.9, shall be given during the checks of the airflow monitoring facility.
The ratio of the response threshold values Nmax : Nmin shall not be greater than 1,6. 6.11 Impact (operational)
6.11.1 Object
To demonstrate the immunity of the detector to mechanical impacts upon its surface, which it may sustain in the normal service environment, and which it can reasonably be expected to withstand.
6.11.2 Test procedure
6.11.2.1 Reference
The test apparatus and procedure shall be as described in EN 60068-2-75, Test Ehb.
6.11.2.2 Initial measurements
Before conditioning, the response threshold value shall be measured as described in 6.1.5.
6.11.2.3 State of the specimen during conditioning
The specimen shall be mounted as described in 6.1.3 to a rigid structure, as required by EN 60068-2¬75, and shall be connected to its supply and monitoring equipment as described in 6.1.2.
6.11.2.4 Conditioning
Impacts shall be applied to all accessible surfaces of the specimen. For all such surfaces three blows shall be applied to any point(s) considered likely to cause damage to or impair the operation of the specimen.
6.11.2.5 Measurements during conditioning
The specimen shall be monitored during the conditioning period to detect any alarm or fault signals.
6.11.2.6 Final measurements
After the conditioning, the function of the airflow monitoring facility shall be checked as described in 6.1.6, and the response threshold value shall be measured as described in 6.1.5.
The maximum and minimum of the response threshold values measured in this test shall be designated Nmax and Nmin respectively.
6.11.3 Requirements
No alarm or fault signals shall be given during the conditioning.
The correct fault signals, in accordance with 5.9, shall be given during the checks of the airflow monitoring facility.
The ratio of the response threshold values Nmax : Nmin shall not be greater than 1,6. 6.12 Vibration, sinusoidal (operational)
6.12.1 Object
To demonstrate the immunity of the detector to vibration at levels considered appropriate to the normal service environment.
6.12.2 Test procedure
6.12.2.1 Reference
The test apparatus and procedure shall be as described in EN 60068-2-6, Test Fc, and as described in 6.12.2.2 to 6.12.2.6.
6.12.2.2 Initial measurements
Before conditioning, the response threshold value shall be measured as described in 6.1.5.
6.12.2.3 State of the specimen during conditioning
The specimen shall be mounted on a rigid fixture as described in 6.1.3 and shall be connected to its supply and monitoring equipment as described in 6.1.2.
The vibration shall be applied in each of three mutually perpendicular axes, in turn, the specimen shall be mounted so that one of the three axes is perpendicular to its normal mounting plane.
NOTE The vibration operational and endurance tests may be combined such that the specimen is subjected to the operational test conditioning followed by the endurance test conditioning in one axis before changing to the next axis. Only one initial and one final measurement need then be made.
6.12.2.5 Measurements during conditioning
The specimen shall be monitored during the conditioning period to detect any alarm or fault signals.
6.12.2.6 Final measurements
After the conditioning, the function of the airflow monitoring facility shall be checked as described in 6.1.6, and the response threshold value shall be measured as described in 6.1.5.
The maximum and minimum of the response threshold values measured in this test shall be designated Nmax and Nmin respectively.
6.12.3 Requirements
No alarm or fault signals shall be given during the conditioning.
The correct fault signals, in accordance with 5.9, shall be given during the checks of the airflow monitoring facility.
The ratio of the response threshold values Nmax : Nmin shall not be greater than 1,6. 6.13 Vibration, sinusoidal (endurance)
6.13.1 Object
To demonstrate the ability of the detector to withstand the long term effects of vibration at levels appropriate to the service environment.
6.13.2 Test procedure 6.13.2.1 Reference
The test apparatus and procedure shall be as described in EN 60068-2-6, Test Fc, and as described in 6.13.2.2 to 6.13.2.5.
6.13.2.2 Initial measurements
Before conditioning, the response threshold value shall be measured as described in 6.1.5.
NOTE The vibration operational and endurance tests may be combined such that the specimen is subjected to the operational test conditioning followed by the endurance test conditioning in one axis before changing to the next axis. Only one initial and one final measurement need then be made.
6.13.2.5 Final measurements
After the conditioning, the function of the airflow monitoring facility shall be checked as described in 6.1.6, and the response threshold value shall be measured as described in 6.1.5.
The maximum and minimum of the response threshold values measured in this test shall be designated Nmax and Nmin respectively.
6.13.3 Requirements
The correct fault signals, in accordance with 5.9, shall be given during the checks of the airflow monitoring facility.
The ratio of the response threshold values Nmax : Nmin shall not be greater than 1,6. 6.14 Electromagnetic compatibility (EMC) immunity tests
EMC immunity tests shall be carried out as described in EN 50130-4:1995. This will mean conducting the following tests:
6.15 Fire sensitivity
6.15.1 Object
To show that the detector has adequate sensitivity to a broad spectrum of smoke types as required for general application in fire detection systems for buildings and other applications as applicable to the class of detector.
6.15.2 Principle
The detector is exposed to a series of test fires with a sampling device suitable for room protection and incorporating the “worst case” arrangement with respect to dilution and transport times, all in accordance with the manufacturer’s recommendations. The test fires are those used for assessing point smoke detectors and the number of sampling points in the fire test room shall be that recommended by the manufacturer to cover the same area as a point smoke detector. Sample points not in the fire test room shall draw in clean air during the tests.
6.15.3 Test procedure 6.15.3.1 Fire test room
The fire sensitivity tests shall be conducted in a rectangular room with a flat horizontal ceiling, and the following dimensions:
Length: 9 m to 11 m, Width: 6 m to 8 m, Height: 3,8 m to 4,2 m.
The fire test room shall be equipped with the following measuring instruments as indicated in Annex I:
Measuring ionization chamber (MIC), Obscuration meter.
6.15.3.2 Test fires
The specimens shall be subjected to test fires (as defined in Annexes B to H) in accordance with Table 4.
Table 4 — Fire test requirements for multi-class detectors
“Config A” means the worst case configuration for the Class A testing; “Config B” means the worst case configuration for the Class B testing; “Config C” means the worst case configuration for the Class C testing;
“=” means that configurations are the same (e.g. Config A = Config B means that the same configuration is used for the Class A testing as for the Class B testing);
“*” means that configurations are different (e.g. Config B * Config C means that a different configuration is used for the Class B testing than for the Class C testing).
The type, quantity and arrangement of the fuel and the method of ignition are described in Annexes B to H for each test fire, along with the end of test conditions and the required profile curve limits. For convenience the EOT conditions are summarized in Table 5:
To be a valid test fire, the development of the fire shall be such that the profile curves. Specifically m against time and m against y (when specified), fall within the specified limits, up to the time when all of the specimens have generated an alarm signal or the end of test condition is reached, whichever is the earlier. If these conditions are not met then the test is invalid and shall be repeated. It is permissible, and may be necessary, to adjust the quantity, condition (e.g. moisture content) and arrangement of the fuel to obtain valid test fires.
The design of the sampling device shall incorporate the “worst case” allowable with respect to the dilution (i.e. the maximum number of sampling points) and transport time (i.e. maximum pipe lengths). This sampling pipe network shall be installed with the worst case sampling point (s) exposed to the test fires. The number of sampling point(s) in the fire test room shall not exceed the minimum number of points that the manufacturer recommends to cover the same area as a point smoke detector. The sampling points in the fire test room shall be mounted in the designated area as defined in the respective annexes and shall be the “worst case” sampling points with respect to the system performance in the tests which may be those points with the longest transport time or those points with the lowest effective sensitivity. The rest of the sampling points shall be arranged outside the fire test room and shall draw in clean air during the tests.
6.15.3.4 Initial conditions
Before each test fire the room shall be ventilated with clean air until it is free from smoke, so that the conditions listed below can be obtained.
The ventilation system shall be switched off and all doors, windows and other openings shall be closed. The air in the room shall then be allowed to stabilize, and the following conditions shall be obtained before the test is started:
Air temperature T: (23 —j) oc,
Air movement: Negligible or stable where the re-circulation fan is operational,
Smoke density (ionization): y < 0,05, Smoke density (optical): m < 0,02 dB m-1.
NOTE The stability of the air and temperature affects the smoke flow within the room. This is particularly important for the test fires which produce low thermal lift for the smoke (e.g. TF2 and TF3). It is therefore recommended that the difference between the temperature near the floor and the ceiling is < 2 °CC, and that local heat sources that can cause convection currents (e.g. lights and heaters) should be avoided. If it is necessary for people to be in the room at the beginning of the test fire they should leave as soon as possible, taking care to produce the minimum disturbance to the air.
6.15.3.5 Recording of fire parameters and response values
During each fire test the fire parameters in Table 6 shall be recorded continuously or at least once per
The aspirating smoke detector shall generate an alarm signal, in each test fire, before a time Tt after the specified end of test condition is reached where the correction time Tt is the transport time for the sampling point(s) in the fire test room up to a maximum of 60 s.
7 Classification and designation
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 classes are defined to enable system designers and installers to select the most appropriate sensitivity.
The manufacturer shall clearly state, in the data presented in 5.11, to which class or classes the aspirating smoke detector is designed. To demonstrate compliance with a specific class the aspirating smoke detector shall be subjected to appropriate fire sensitivity test as defined in 6.15.
Table 7 provides a summary of the various classes of detector and the corresponding fire tests used for the classification.a) number of this standard and the class(es) to which it conforms identify, at least, the date or batch and place of manufacture, and the version number(s) of any software, contained within the detector.
Where any marking on the device uses symbols or abbreviations not in common use, these shall be explained in the data supplied with the device.
The marking shall be visible during installation and shall be accessible during maintenance. The markings shall not be placed on screws or other easily removable parts.
Apparatus for Response Threshold Value (RTV) measurements
To measure the response threshold value of an aspirating smoke detector, it is essential to be able to generate an aerosol in a precisely controlled manner so that the detector can be subjected to sampled air with a slowly and consistently increasing aerosol concentration, and to be able to obtain a measure of the concentration which is essentially proportional to the particle number concentration.
To test the wide range of types and classes of aspirating detectors, either it should be possible to adjust the test apparatus to give a wide range of airflow rates and aerosol concentrations, or different sets of test apparatus should be utilized to suit the various types and classes of ASD.
It is essential that the test apparatus used is capable of generating repeatable results.
The following three examples are provided for the guidance of the test houses. All three consist of four main functional blocks: aerosol generation, aerosol dilution, aerosol measurement and the DUT (see
The development of the fire shall be such that the curves of m against time for TF5A and TF5B fall within the limits shown in Figure H.2 and H.3 respectively, up to the time when m = EOT condition, or the specimen has generated an alarm signal, whichever is the earliest.