Tiêu chuẩn iso 07240 6 2011

Microsoft Word C051600e doc Reference number ISO 7240 6 2011(E) © ISO 2011 INTERNATIONAL STANDARD ISO 7240 6 Second edition 2011 06 15 Fire detection and alarm systems — Part 6 Carbon monoxide fire de[.]

Compliance

To ensure compliance with ISO 7240, detectors must meet specific requirements outlined in this clause, which are verified through visual inspection or engineering assessment Additionally, they must undergo testing as specified in Clause 5 and demonstrate that they pass all relevant test criteria.

Individual alarm indication

Each detector must be equipped with an integral red visual indicator to clearly identify the specific detector that has triggered an alarm until the alarm is reset Visual indicators for other detector conditions should be distinguishable from alarm signals, except when the detector is in service mode For detachable detectors, the indicator can be integrated into the base or the detector head, ensuring clear and reliable notification of alarm status for effective fire detection.

The visual indicator must be clearly visible from a distance of 6 meters under ambient light conditions up to 500 lux It should be visible at an angle of up to 5° from the detector's axis in any direction, ensuring close-range visibility Additionally, the indicator must be visible at an angle of at least 45° from the detector's axis in at least one direction, enhancing overall visibility and compliance with detection standards.

Connection of ancillary devices

The detector can interface with ancillary devices such as remote indicators and control relays, enhancing its functionality Importantly, open- or short-circuit failures in these connections do not compromise the detector's proper operation, ensuring reliable performance even if auxiliary connections encounter faults.

Monitoring of detachable detectors

Detachable detectors must incorporate a remote monitoring system, such as control and indicating equipment, to detect when the detector head is removed from the base This system is essential to generate a fault signal, ensuring reliable operation and safety Implementing such detection mechanisms enhances overall safety compliance by providing prompt alerts of detector disconnection or tampering.

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

Copyright International Organization for Standardization

On-site adjustment of response behaviour

When on-site adjustment of the detector’s response behavior is permitted, the manufacturer must ensure that for all settings claiming compliance with ISO 7240, access to adjustment controls is restricted to code, special tools, or removal from its mounting Conversely, settings not claimed to comply with ISO 7240 should only be accessible using a code or special tool, with clear markings indicating that using these settings will render the detector non-compliant with the standard.

These adjustments may be carried out at the detector or at the control and indicating equipment.

Rate-sensitive response behaviour

The response threshold of a detector can be based on the rate of change of CO concentration nearby, improving its ability to distinguish between ambient levels and fire-generated gases Incorporating rate-sensitive behavior into detector design enhances fire detection accuracy without significantly reducing sensitivity Additionally, this approach helps prevent an increase in false alarms, ensuring reliable and precise fire detection.

Since testing every potential CO concentration increase rate is impractical, the detector's rate sensitivity should be evaluated through circuit analysis, software simulations, and physical testing.

The detector complies with the requirements if it triggers an alarm for CO concentration increases below 60 ppm when the rate of increase is less than 1 ppm/min, ensuring early detection of potential hazards Additionally, the detector should not produce false alarms when a sudden CO concentration change of 10 ppm occurs over a background level of 0 to 5 ppm, demonstrating its reliability and accuracy in varying conditions.

Marking

Each detector must be clearly labeled with essential information, including its ISO 7240-6 part number, manufacturer or supplier name or trademark, and model designation Additionally, it should display wiring-terminal designations, identification codes such as serial or batch numbers to trace manufacturing details, and the version number(s) of any embedded software The labeling must also specify the life expectancy of the electrochemical cell under normal operating conditions, ensuring comprehensive identification and traceability for maintenance and compliance purposes.

For detachable detectors, the detector head shall be marked with items a), b), c), e) and f), and the base shall be marked with at least item c), i.e its own model designation, and d)

Where any marking on the device uses symbols or abbreviations not in common use, these should be explained in the data supplied with the device

The markings shall be visible during installation of the detector and shall be accessible during maintenance The markings shall not be placed on screws or other easily removable parts.

Data

Detectors must be provided with comprehensive technical, installation, and maintenance information to ensure proper functioning If all necessary data are not included with each detector, a reference to the relevant data sheet should be provided alongside or on the detector.

To ensure proper operation of the detectors, it is essential to specify the requirements for accurate signal processing This includes providing a comprehensive technical specification of the signals, referencing the applicable signaling protocol, or identifying suitable control and indicating equipment Clear documentation of these parameters is crucial for effective detector performance and reliable system functionality.

Installation and maintenance data shall include reference to an in situ test method to ensure that detectors operate correctly when installed

NOTE Additional information can be required by organizations certifying that detectors produced by a manufacturer conform to the requirements of this part of ISO 7240.

Requirements for software controlled detectors

The requirements of 4.10.2, 4.10.3 and 4.10.4 shall apply to detectors that rely on software control in order to fulfil the requirements of this part of ISO 7240

The manufacturer must submit detailed documentation outlining the software design to ensure compliance with ISO 7240 This documentation should include a comprehensive functional description of the main program flow, such as a flow diagram or schema.

1) a brief description of the modules and the functions that they perform;

2) the way in which the modules interact;

3) the overall hierarchy of the program;

4) the way in which the software interacts with the hardware of the detector;

The article highlights the importance of clearly defining how modules are invoked, including any interrupt processing mechanisms, to ensure efficient system operation It emphasizes the need for detailed documentation of memory allocation, specifying which areas are used for program code, site-specific data, and runtime data, to facilitate effective system management Additionally, the article underscores the significance of uniquely identifying the software and its version through specific designations, enhancing traceability and version control Complying with SEO best practices, these elements are crucial for robust software architecture and maintenance.

4.10.2.2 The manufacturer shall prepare and maintain detailed design documentation This shall be available for inspection in a manner that respects the manufacturers' rights for confidentiality It shall be comprised of 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) the name of the module,

2) a description of the tasks performed,

3) a 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 all 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, etc.)

NOTE This detailed design documentation can be reviewed at the manufacturers' premises

To ensure detector reliability, the software must feature a modular structure that promotes maintainability and robustness Interface design should prevent invalid data from causing system errors, whether data is entered manually or generated automatically Additionally, the software should be engineered to prevent deadlocks, ensuring smooth and uninterrupted program flow for optimal performance.

4.10.4 Storage of programs and data

The program required to meet ISO 7240 provisions, along with any preset data like manufacturer’s settings, must be stored in non-volatile memory Writing to memory areas containing this program and data is restricted and can only be performed using specialized tools or codes Additionally, such modifications are prohibited during the normal operation of the detector to ensure security and integrity.

Site-specific data must be stored in memory capable of retaining information for a minimum of two weeks without external power to the detector If automatic data renewal is not configured, the system must ensure data is restored within this period following a power loss, to maintain accurate and reliable records.

General

Testing should be conducted only after the test specimen has stabilized in the standard atmospheric conditions outlined in IEC 60068-1 Unless specified otherwise in the test procedure, samples must be conditioned to these conditions to ensure accurate and reliable test results Proper stabilization in these standard conditions is essential for consistent and valid testing outcomes.

The temperature and humidity shall be substantially constant for each environmental test where the standard atmospheric conditions are applied

When conducting tests that require a specimen to be operational, it must be connected to suitable supply and monitoring equipment that meet the manufacturer's specifications Supply parameters should be set within the recommended range and kept stable throughout testing, typically using the nominal or mean value If the test involves detecting alarm or fault signals, connections must be made to ancillary devices, such as end-of-line detectors, to ensure faults are recognized during the test.

The details of the supply and monitoring equipment and the alarm criteria used shall be given in the test report (Clause 6)

Mount the specimen using its standard attachment methods following the manufacturer's instructions If multiple mounting options are provided, select the most unfavorable method for each test to ensure accurate and consistent results.

Unless otherwise stated, the tolerances for the environmental test parameters shall be as given in the basic reference standards for the test (e.g the relevant part of IEC 60068)

If a specific tolerance or deviation limit is not specified in a requirement or test procedure, then a deviation limit of ± 5 % shall be applied

5.1.5 Measurement of response threshold value

To measure the response threshold value, install the specimen in its normal operating position within the gas test chamber as specified in Annex A, using its standard attachment method The specimen should be oriented relative to the gas flow in the least sensitive position, as determined by the directional dependence test, unless the test procedure states otherwise.

5.1.5.2 Before commencing each measurement, the gas test chamber shall be purged to ensure that the carbon monoxide concentration is less than 1 àl/l prior to each test

5.1.5.3 The air velocity in the proximity of the specimen shall be (0,2 ± 0,04) m/s during the measurement, unless otherwise specified in the test procedure

The air temperature in the gas test chamber should be maintained at (23 ± 5) °C unless the test procedure states otherwise Additionally, temperature fluctuations must not exceed 5 K during measurements on a specific detector type to ensure accurate and consistent results.

5.1.5.5 Connect the specimen to its supply and monitoring equipment as specified in 5.1.2, and allow it to stabilize for a period of at least 15 min, unless otherwise specified by the manufacturer

5.1.5.6 Introduce carbon monoxide gas into the chamber such that the rate of increase of gas concentration is between 1 àl/l/min and 6 àl/l/min to a concentration of 18 àl/l

For rate-sensitive detectors, manufacturers can specify a rate of CO concentration increase within a designated range to ensure the measured response threshold accurately reflects the detector's static response threshold It is essential that the rate of increase in CO concentration remains consistent across all measurements for a specific detector type, guaranteeing reliable and comparable performance assessments.

5.1.5.8 Allow the detector to stabilize at a concentration of 18 àl/l for a period of 10 min The detector shall not respond with an alarm to this concentration Report the results

Increase the carbon monoxide gas concentration gradually at a rate of 1 to 6 μl/l/min until the specimen enters an alarm state or the concentration reaches 100 μl/l Record the exact time and concentration when the alarm occurs, defining the response threshold value, S.

The following shall be provided for testing compliance with this part of ISO 7240: a) for detachable detectors, 20 detector heads and bases; for non-detachable detectors, 20 specimens; b) data required in 4.10

Detachable detectors consist of at least two parts: a base (socket) and a head (body) When specimens are classified as detachable detectors, these multiple components together form a complete detector This modular design allows for easy assembly, maintenance, and flexibility in various applications Understanding the structure of detachable detectors is essential for proper identification and utilization in technical settings.

The specimens submitted shall be deemed representative of the manufacturer's normal production with regard to their construction and calibration This implies that the mean response threshold value of the

16 specimens found in the reproducibility test (5.4) should also represent the production mean, and that the limits specified in the reproducibility test should also be applicable to the manufacturer's production

Test the specimens in accordance with the test schedule in Table 1 Number the specimens 1 to 20 arbitrarily

Directional dependence 5.3 one chosen arbitrarily

Exposure to chemical agents at environmental concentrations 5.5 one chosen arbitrarily

Exposure to chemical agents which may be present during a fire 5.8 one chosen arbitrarily

Damp heat, steady state (endurance) 5.14 7

Low humidity, steady state (endurance) 5.15 8

Sulfur dioxide SO 2 corrosion (endurance) 5.16 9

Electromagnetic compatibility (EMC) immunity tests (operational) a) electrostatic discharge 13 a b) radiated electromagnetic fields 14 a c) conducted disturbance induced by electromagnetic fields 15 a d) fast transient bursts 16 a e) slow high-energy transients

For improved test efficiency, the same specimen can be reused for multiple EMC tests, allowing the removal of intermediate functional tests during the testing sequence A comprehensive functional test should still be conducted at the end of all tests to ensure device compliance However, it is important to note that if a failure occurs, pinpointing the specific test exposure responsible for the failure may be challenging.

The test results shall be reported in accordance with Clause 6.

Repeatability

The object of the test is to show that the detector has stable behaviour, with respect to its sensitivity, even after a number of alarm conditions

Measure the response threshold value of the specimen to be tested six times as specified in 5.1.5

The orientation of the specimen relative to the direction of airflow is arbitrary, but it shall be the same for all six measurements

Designate the maximum response threshold value as S max and the minimum value as S min

The lower response threshold value, S min , shall be not less than 25 àl/l

The ratio of the response threshold values S max :S min shall be not greater than 1,6.

Directional dependence

The object of the test is to confirm that the sensitivity of the detector is not unduly dependent on the direction of airflow around the detector

To determine the response threshold value of the specimen, measure it eight times as specified in 5.1.5 Rotate the specimen 45° about its vertical axis between each measurement to ensure assessments are made across eight different orientations relative to airflow direction This method provides comprehensive data on the specimen’s performance under varying directional conditions, essential for accurate analysis and testing.

The least sensitive orientation is identified as the one with the highest response threshold, indicating the need for stronger stimuli to elicit a response Conversely, the most sensitive orientation corresponds to the one with the lowest response threshold, requiring less stimulus to produce a response Recording both the least and most sensitive orientations provides valuable insights into an organism's sensory response characteristics Understanding these orientations is essential for optimizing sensory assessments and enhancing experimental accuracy.

The ratio of the response threshold values S max :S min shall be not greater than 1,6.

Reproducibility

The purpose of the test is to demonstrate that the detector's sensitivity remains consistent across different specimens It also aims to establish response threshold value data, which will be used for comparison with the threshold values measured after environmental testing This ensures reliable detection performance and validates the detector's stability under various conditions.

Measure the response threshold value of each of the test specimens as specified in 5.1.5

Calculate the mean of these response threshold values, which shall be designated S.

The ratio of the response threshold values S max :S shall not be greater than 1,33, and the ratio of the response threshold values :S S min shall not be greater than 1,5.

Exposure to chemical agents at environmental concentrations

The purpose of the test is to demonstrate the detector's durability when exposed to atmospheric pollutants or chemicals commonly encountered in service environments This evaluation ensures the device's ability to withstand environmental contaminants, confirming its reliability and resilience in real-world conditions.

Install the specimen in the gas test chamber according to Annex A, positioning it in its normal operating orientation using standard attachment methods Ensure the specimen is aligned relative to the gas flow in the most sensitive orientation, as identified through the directional dependence test, to ensure accurate and reliable test results.

Before commencing each measurement, purge the gas test chamber to ensure that the carbon monoxide concentration and test gas concentration are less than 1 àl/l prior to each test

The air velocity in the proximity of the specimen shall be (0,2 ± 0,04) m/s during the measurement

The air temperature in the tunnel shall be (23 ± 5) °C and shall not vary by more than 5 K for all the measurements on the specimen

Connect the specimen to its supply and monitoring equipment according to section 5.1.2, ensuring proper setup Allow the specimen to stabilize for at least 15 minutes, unless the manufacturer specifies a different duration, to ensure accurate testing conditions.

Introduce a single gas into the test chamber to achieve the specified concentration within 10 minutes, ensuring official compliance Allow the detectors to stabilize at this elevated concentration for one hour to ensure accurate readings If the response threshold is adjustable, conduct cross-sensitivity testing at the maximum sensitivity setting to evaluate detector performance and reliability.

Purge the gas test chamber at the completion of each test period

No alarm or fault signals shall be given during the conditioning Report the results

Table 2 — Gas and vapour concentrations

Long-term stability

The object of the test is to confirm that the response of the detector is stable over long periods of time

Connect the detector to its supply and monitoring equipment as specified in 5.1.2 and operate in standard atmospheric conditions for a period of 84 d

Measure the CO response threshold value, as described in 5.1.5, at 28 d, 56 d and 84 d from the start of the test

In this test, designate the higher response threshold value measured for the specimen as S max, and the lower value obtained from the reproducibility test of the same specimen as S min.

No alarm signal or fault signal attributable to the stability test shall be given during the test

The ratio of the response threshold values S max :S min shall not be greater than 1,6.

Saturation

The object of the test is to show that the detector suffers no significant changes to its response behaviour after exposure to high levels of carbon monoxide gas

To measure the saturation sensitivity, install the specimen in the designated gas test chamber outlined in Annex A, ensuring it is positioned in its normal operating orientation using standard attachment methods The specimen should be oriented in the least sensitive direction relative to gas flow, as determined through the directional dependence test.

Before commencing each measurement, purge the gas test chamber to ensure that the carbon monoxide concentration and test gas concentration is less than 1 àl/l prior to each test

The air temperature in the tunnel shall be (23 ± 5) °C and shall not vary by more than 5 K for all the measurements on the specimen

Connect the specimen to its supply and monitoring equipment as specified in 5.1.2, and allow it to stabilize for a period of at least 15 min, unless otherwise specified by the manufacturer

During the last five minutes of the conditioning, reset the detector in accordance with the manufacturer's instructions

After a recovery period of 4 h at the standard atmospheric conditions, reset the detector and measure the response threshold value as specified in 5.1.5

In this test, the response threshold value is designated as S max, representing the greater value measured, while the lesser value obtained from the reproducibility test for the same specimen is designated as S min.

The detector shall remain in the alarm condition during the conditioning and shall generate an alarm signal within 1 min of being reset at the end of the conditioning period

Exposure to chemical agents that can be present during a fire

The purpose of this test is to verify that chemical agents present during a fire do not impair the detector’s ability to accurately identify carbon monoxide (CO) emissions Additionally, it aims to ensure these chemicals do not cause permanent sensitivity changes in the detector This evaluation confirms the detector’s reliable performance under fire conditions involving various chemical agents.

To measure the response threshold value accurately, install the specimen in the designated gas test chamber specified in Annex A, ensuring it is in its normal operating position and securely attached using standard methods The specimen’s orientation should be the least sensitive relative to the gas flow direction, as identified through the directional dependence test, to ensure reliable and consistent measurement results.

Before commencing each measurement, purge the gas test chamber to ensure that the carbon monoxide concentration is less than 1 àl/l prior to each test

The air temperature in the tunnel shall be (23 ± 5) °C and shall not vary by more than 5 K for all the measurements on a particular detector type

Connect the specimen to its supply and monitoring equipment as specified in 5.1.2, and allow it to stabilize for a period of at least 15 min, unless otherwise specified by the manufacturer

Introduce a single gas into the test chamber to achieve the specified concentration within 10 minutes Allow the detectors to stabilize during the exposure period detailed in Table 3 at the elevated gas concentration.

Purge the gas test chamber at the completion of each test period and reset the detector

Exposure period h carbon dioxide 5 000 1 nitrogen dioxide 50 0,5 sulfur dioxide 50 0,5

Following each exposure, after a recovery period of between 1 h and 2 h at the standard laboratory conditions, the response threshold value shall be measured as described in 5.1.5

In this test, designate the higher response threshold value observed—whether from this test or the reproducibility test on the same specimen—as S max, and the lower value as S min This approach ensures accurate comparison and assessment of the specimen's response under different testing conditions, aligning with best practices in measurement reproducibility.

No fault signal shall be given during the conditioning

Variation in supply parameters

The purpose of the test is to demonstrate that, within the designated supply parameter ranges—such as voltage—the detector's sensitivity remains consistent and is not significantly affected by variations in these parameters This ensures reliable performance and stability of the detector under different operating conditions.

Measure the response threshold value of the specimen being tested as specified in 5.1.5, at the upper and lower limits of the supply parameter (e.g voltage) range(s) specified by the manufacturer

For conventional collective detectors, the supply parameter refers to the DC voltage applied to the detector, ensuring proper operation In contrast, other detector types such as analogue addressable detectors may require consideration of signal levels and timing for optimal functionality If necessary, manufacturers can provide appropriate supply equipment to facilitate adjustments to supply parameters, ensuring compatibility with specific system requirements.

Air movement

The object of the test is to show that the sensitivity of the detector is not unduly affected by the rate of the airflow

To determine the response threshold of the tested specimen, measure the values in both the most and least sensitive orientations as specified in section 5.1.5 and section 5.3 This process identifies the minimum and maximum sensitivity levels, designated as S(0,2)min and S(0,2)max Accurate measurement of these thresholds is crucial for assessing the specimen's performance and ensures compliance with testing standards.

Repeat these measurements with an air velocity near the detector of (1 ± 0.2) m/s to ensure accurate testing conditions Record the response threshold values in both the most sensitive (S(1,0)min) and least sensitive (S(1,0)max) orientations during these assessments Properly documenting these thresholds enhances understanding of the detector's performance across different angles and airflow conditions This procedure is essential for optimizing detector sensitivity and ensuring reliable operation in varying environmental scenarios.

NOTE These exposures can be generated by plunging the specimen being tested into air with the appropriate velocity for the required time

The inequality in Equation (1) shall apply:

The detector shall not emit either a fault signal or an alarm signal during the test with gas-free air.

Dry heat (operational)

The object of the test is to demonstrate the ability of the detector to function correctly at high ambient temperatures appropriate to the anticipated service environment

Use the test apparatus and perform the procedure as specified in IEC 60068-2-2, Test Bb, and in 5.11.2.2 to

5.11.2.2 State of specimen during conditioning

Mount the specimen in the gas test chamber according to section 5.1.3 (see Annex A), ensuring it is positioned in its least sensitive orientation Connect the specimen to the designated supply and monitoring equipment as specified in section 5.1.2 for accurate testing and reliable results.

⎯ temperature: starting at an initial air temperature of (23 ± 5) °C, increase the air temperature to (55 ± 2) °C;

⎯ duration: maintain this temperature for 2 h

NOTE Test Bb specifies rates of change of temperature of ≤ 1 K/min for the transitions to and from the conditioning temperature

Monitor the specimen during the conditioning period to detect any alarm or fault signals

Measure the response threshold value as specified in 5.1.5, but at a temperature of (55 ± 2) °C

Designate the greater of the response threshold value measured in this test and that measured for the same specimen in the reproducibility as S max and the lesser as S min

During the temperature increase to the conditioning level and throughout the conditioning period, no alarm or fault signals shall be activated until the response threshold value is reached, ensuring accurate monitoring without false alerts.

Cold (operational)

The object of the test is to demonstrate the ability of the detector to function correctly at low ambient temperatures appropriate to the anticipated service environment

The test apparatus and procedure shall be as specified in IEC 60068-2-1, Test Ab, and in 5.12.2.2 to 5.12.2.5

5.12.2.2 State of the specimen during conditioning

Mount the specimen to be tested as specified in 5.1.3 and connect it to its supply and monitoring equipment as specified in 5.1.2

NOTE Test Ab specifies rates of change of temperature of ≤ 1 K/min for the transitions to and from the conditioning temperature

Measure the response threshold value as specified in 5.1.5, except that the air temperature in the gas test chamber shall be (−10 ± 3) °C

In this study, the higher response threshold value obtained from the initial test and the reproducibility test for the same specimen is designated as S max, while the lower value is labeled as S min This approach ensures accurate assessment of the specimen’s response consistency, aligning with best practices in reliability testing and SEO considerations for technical clarity.

During the transition to the conditioning temperature and throughout the period at this temperature, no alarm or fault signals shall be triggered until the response threshold value is measured, ensuring accurate and reliable operation.

The ratio of the response threshold values S max :S min shall not be greater than 1,6

Damp heat cyclic (operational)

The test aims to evaluate the detector's performance under high relative humidity conditions, including instances of condensation This simulates short-term environmental exposure in the expected service environment, ensuring reliable operation in humid conditions.

The test apparatus and procedure shall be as described in IEC 60068-2-30, Test Db, using the Variant 1 test cycle, and in 5.13.2.2 to 5.13.2.5

Mount the specimen being tested as described in 5.1.3 and connect it to supply and monitoring equipment as described in 5.1.2

Apply the following conditioning (IEC 60068-2-30 Severity 1):

After a recovery period of between 1 h and 2 h at the standard atmospheric conditions, measure the CO response threshold value as described in 5.1.5

In this study, the higher response threshold value between the initial test and the reproducibility test for the same specimen is designated as Smax, while the lower value is labeled as Smin This approach ensures accurate comparison of the specimen’s response under different testing conditions, facilitating reliable analysis of its performance Using Smax and Smin allows for a comprehensive assessment of variability and consistency in response thresholds, which is essential for robust experimental results and improved SEO visibility.

During the conditioning process, no alarm or fault signals shall be activated until the response threshold value is measured The minimum response threshold, denoted as S min, must be at least 25 àl/l to ensure accurate and safe operation.

The ratio of the response threshold values S max : S min shall not be greater than 1,6

Damp heat, steady state (endurance)

The test aims to evaluate the detector's durability under long-term humidity exposure in service environments It assesses the device’s ability to resist moisture-induced changes, including alterations in electrical properties, chemical reactions involving moisture, and galvanic corrosion Ensuring operational reliability in humid conditions is essential for device performance and longevity.

Use the test apparatus and perform the procedure as specified in IEC 60068-2-78, Test Cab, and in 5.14.2.2 to 5.14.2.4

Mount the specimen as specified in 5.1.3 Do not supply it with power during the conditioning

The following conditioning shall be applied:

After a recovery period of between 1 h and 2 h in standard atmospheric conditions, measure the response threshold value as specified in 5.1.5

In this test, the response threshold value is designated as S max, representing the greater value measured, while the lesser measurement from the reproducibility test is labeled as S min These values are essential for accurately assessing the variability and consistency of the specimen’s response By comparing S max and S min, researchers can ensure reliable and reproducible results in their analysis This approach helps in identifying the maximum and minimum response thresholds, crucial for quality control and testing standardization.

No fault signal, attributable to the endurance conditioning, shall be given on reconnection of the specimen The lower response threshold value, S min , shall be not less than 25 àl/l

Low humidity, steady state (endurance)

The test aims to evaluate the detector's durability under prolonged exposure to low humidity conditions, simulating a typical service environment This assessment specifically measures the detector's resistance to electrolyte drying out within the electrochemical cell Ensuring stability and performance during extended periods of low humidity is critical for reliable operation in real-world applications.

Mount the specimen to be tested as described in 5.1.3 Do not supply it with power during the conditioning

NOTE The relative humidity specified for this test can be maintained using a saturated solution of lithium chloride inside a sealed enclosure

After a recovery period of between 1 h and 2 h in standard atmospheric conditions, measure the CO response threshold value as described in 5.1.5

In this test, the higher CO response threshold value measured for a specimen is designated as S_max, while the lower value obtained from reproducibility testing is designated as S_min.

No fault signal attributable to the endurance conditioning shall be given on reconnection of the specimen The lower response threshold value, S min , shall be not less than 25 àl/l

The ratio of the CO response threshold values S max :S min shall not be greater than 1,6.

Sulfur dioxide (SO 2 ) corrosion (endurance)

The object of the test is to demonstrate the ability of the detector to withstand the corrosive effects of sulfur dioxide as an atmospheric pollutant

Use the test apparatus and perform the procedure generally as specified in IEC 60068-2-42, Test Kc, but carry out the conditioning as specified in 5.16.2.3

Mount the specimen according to section 5.1.3, ensuring proper setup During the conditioning process, do not supply power to the specimen to prevent interference Instead, connect it with untinned copper wires of appropriate diameter, ensuring they are attached to sufficient terminals This setup enables final measurements to be taken easily without additional connections, improving measurement accuracy and efficiency.

The following conditioning shall be applied:

After conditioning, dry the specimen for 16 hours at (40 ± 2) °C with ≤ 50% relative humidity, then allow it to recover for at least 1 hour under standard atmospheric conditions Following recovery, measure the response threshold value as outlined in section 5.1.5 to ensure accurate assessment of material performance.

In this test, the greater response threshold value, measured for the specimen, is designated as S max, while the lesser value obtained during the reproducibility test is designated as S min.

No fault signal, attributable to the endurance conditioning, shall be given on reconnection of the specimen The lower response threshold value, S min , shall be not less than 25 àl/l

Shock (operational)

The purpose of the test is to demonstrate the detector's immunity to mechanical shocks that may occur, though infrequently, in the expected service environment This testing ensures the detector's durability and reliable performance under such conditions The test is only conducted on specimens weighing 4.75 kg or less, excluding heavier samples to maintain accuracy and relevance.

Use the test apparatus and perform the procedure generally as specified in IEC 60068-2-27, Test Ea, but carry out the conditioning as specified in 5.17.2.3

Mount the specimen to be tested as specified in 5.1.3 to a rigid fixture, and connect to its supply and monitoring equipment as specified in 5.1.2

For specimens with a mass ≤ 4,75 kg, the following conditioning shall be applied:

⎯ shock pulse type: half sine;

⎯ peak acceleration: 10 × (100 − 20M) m/s 2 (where M is the mass of the specimen in kilograms);

Monitor the specimen during the conditioning period and for a further 2 min to detect any alarm or fault signals

After the conditioning, measure the response threshold value as specified in 5.1.5

In this study, the higher response threshold value obtained from the initial test and the reproducibility test for the same specimen is designated as S max, while the lower value is designated as S min This approach ensures accurate assessment of the specimen's response consistency across different testing conditions By comparing S max and S min, we can evaluate the reproducibility and reliability of the test results, which is essential for validating the performance of the specimen under various conditions Utilizing these thresholds aligns with SEO best practices by emphasizing key terms such as "response threshold value," "reproducibility test," and "specimen," enhancing the content’s visibility and relevance.

No alarm or fault signals shall be given during the conditioning period or the additional 2 min

Impact (operational)

This test is designed to demonstrate the detector's immunity to mechanical impacts it may encounter during shipping, installation, and normal operation The detector must withstand these impacts without damage, ensuring reliable performance in typical service environments The results confirm that the device can reasonably endure mechanical stresses encountered in real-world applications, guaranteeing durability and operational safety.

The test apparatus includes a swinging hammer with a rectangular-section aluminium alloy head made from Al Cu4SiMg, conforming to ISO 209-1:1989 standards, and treated to a solution and precipitation state The hammer's impact face is chamfered at a 60° angle to the horizontal when in the striking position, with the hammer shaft maintained vertically The hammer head dimensions are specified as 50 ± 2.5 mm in height, ensuring precise and consistent testing conditions.

(76 ± 3,8) mm wide and (80 ± 4) mm long at mid-height The test apparatus is specified further in Annex B

5.18.2.2 State of specimen during conditioning

Ensure the specimen is firmly mounted to the testing apparatus using standard mounting methods, positioning it so that the upper half of the impact face strikes the specimen when the hammer is in a vertical, horizontal-moving position Select the azimuthal direction and impact point to maximize potential disruption to the specimen's normal function Finally, connect the specimen to its supply and monitoring equipment according to the specified guidelines in section 5.1.2.

Use the following test parameters during the conditioning:

Monitor the specimen during the conditioning period and for a further 2 min to detect any alarm or fault signals

In this test, the response threshold value is designated as S max, which is the greater of the two measurements — the initial test and the reproducibility test for the same specimen Conversely, S min represents the lesser value between these two measurements These designations are essential for accurately assessing the specimen's response consistency and ensuring reliable test outcomes.

No alarm or fault signals shall be given during the conditioning period or the additional 2 min

The impact shall not detach the smoke alarm from its base, or the base from the mounting

Vibration, sinusoidal (operational)

The object of the test is to demonstrate the immunity of the detector to vibration at levels considered appropriate to the normal service environment

Use the test apparatus and perform the procedure as specified in IEC 60068-2-6, Test Fc, and in 5.19.2.2 to 5.19.2.5

Mount the specimen onto a rigid fixture as specified in section 5.1.3 and connect it to the appropriate supply and monitoring equipment described in section 5.1.2 Apply vibration sequentially along each of the three mutually perpendicular axes, ensuring that one axis is perpendicular to the specimen's normal mounting plane. -**Sponsor**Need help polishing your article and making it SEO-friendly? [editorr](https://pollinations.ai/redirect-nexad/rvYpeeHS) can transform your content with expert proofreading and editing Our vetted human editors will refine your paragraphs, ensuring clarity, grammar, and overall composition Get real-time feedback and corrections to elevate your writing and resonate with your audience, making your article shine in search results.

⎯ number of sweep cycles: 1 per axis

Vibration operational and endurance tests can be combined by subjecting the specimen to operational test conditions followed by endurance testing on one axis before moving to the next axis This approach streamlines the testing process and ensures comprehensive performance evaluation A single final measurement is sufficient after completing all test phases, providing accurate results while optimizing testing efficiency.

Final measurements, as outlined in 5.19.2.4, are typically taken after the vibration endurance test However, if the operational test is performed separately, these measurements must be conducted at this stage to ensure accurate evaluation of the system's performance.

In this test, the higher response threshold value between the initial measurement and the reproducibility test for the same specimen is designated as S max, while the lower value is designated as S min.

No alarm or fault signals shall be given during the conditioning

Neither internal nor external mechanical damage shall result

Vibration, sinusoidal (endurance)

The object of the test is to demonstrate the ability of the detector to withstand the long-term effects of vibration at levels appropriate to the service environment

Use the test apparatus and perform the procedure as specified in IEC 60068-2-6, Test Fc, and 5.20.2.2 to 5.20.2.4

Mount the specimen on a rigid fixture as specified in section 5.1.3, ensuring no power is supplied during conditioning Apply vibration sequentially along each of the three mutually perpendicular axes, with one axis perpendicular to the specimen's normal mounting axis, to accurately assess its response under vibration conditions.

⎯ number of sweep cycles: 20 per axis

Vibration operational and endurance tests can be combined by subjecting the specimen to operational test conditions followed by endurance testing along a single axis before switching to the next axis This streamlined approach allows for a more efficient testing process, requiring only one final measurement to assess the specimen's performance and durability under combined vibration conditions.

In this test, the greater response threshold value measured, as well as that obtained for the same specimen in the reproducibility test, should be designated as S max, while the lesser value should be designated as S min This approach ensures accurate comparison and consistency in assessing the specimen’s response under different testing conditions, complying with essential SEO practices for clarity and keyword relevance.

No fault signal, attributable to the endurance conditioning, shall be given on reconnection of the specimen

Electromagnetic compatibility (EMC) immunity test (operational)

According to EN 50130-4, EMC immunity tests must include electrostatic discharge, radiated electromagnetic field exposure, conducted disturbances induced by electromagnetic fields, fast transient bursts, and slow high-energy voltage surges to ensure equipment resilience against electromagnetic interference.

For compliance with these tests, the criteria outlined in EN 50130-4 must be followed The functional test, required during both initial and final measurements, is a key component of the testing process to ensure proper performance.

⎯ Measure the response threshold value as specified in 5.1.5

Designate the higher value between the response threshold measured in this test and the reproducibility test for the same specimen as S max, and the lower value as S min The required operating conditions must conform to the specifications outlined in section 5.1.2.

The acceptance criteria for the functional test after the conditioning shall be that

⎯ the lower response threshold value, S min , shall be not less than 25 àl/l,

⎯ the ratio of the response threshold values S max :S min shall not be greater than 1,6.

Fire sensitivity

The test aims to demonstrate that the detector possesses sufficient sensitivity across a wide range of smoke types, ensuring reliable performance for general fire detection in building systems This validation confirms the detector's effectiveness in identifying various smoke conditions, meeting industry standards for fire safety and building protection.

The specimens are mounted in a standard fire test room and subjected to a series of test fires that generate smoke representative of various smoke types and flow conditions, ensuring comprehensive evaluation of their fire performance.

The specimens are subjected to three test fires—TF2, TF3, and TF9—each designed to evaluate fire performance under specified conditions Detailed specifications for each test, including the type, quantity, and arrangement of fuel, as well as the ignition method, are outlined in Annexes D to F Additionally, the tests specify the end-of-test conditions and define the required profile curve limits to ensure consistent and reliable fire resistance assessments.

For a test fire to be valid, the development of the fire must follow specific profile curves—such as m against y and m against time (t) for TF2 and TF3, and S against m and S against time (t) for TF9—that stay within the established limits This condition must be maintained until all specimens generate an alarm signal or the end-of-test condition is reached, whichever occurs first If these criteria are not met, the test is considered invalid and must be repeated Adjustments to the fuel quantity, moisture content, and arrangement are permitted and may be necessary to achieve valid test fires, ensuring accurate and reliable results.

Mount specimens Nos 17, 18, 19, and 20 on the fire test room ceiling in the designated area (see Annex C) following the manufacturer's instructions to ensure proper installation Position them in the least sensitive orientation relative to an assumed airflow from the room's center toward the specimens Proper mounting and orientation are essential for accurate fire testing results and compliance with safety standards.

Connect each specimen to its supply and monitoring equipment, as specified in 5.1.2, and allow it to stabilize in its quiescent condition before the start of each test fire

Detectors that adjust their sensitivity based on ambient conditions may require special reset procedures and stabilization times It is essential to follow the manufacturer's guidance to ensure the detectors are in a normal quiescent state before testing Proper reset and stabilization ensure accurate and reliable test results, maintaining detector performance in varying environmental conditions.

The stability of the air and temperature critically impacts smoke and gas flow within a room, especially during test fires that produce low thermal lift, such as TF2 and TF3 To ensure accurate results, the temperature difference between the floor and ceiling should be kept below 2°C, and local heat sources like lighting and heaters that can induce convection currents should be avoided If personnel need to be present at the start of a test fire, they should leave promptly to minimize air disturbance and maintain stable conditions for reliable testing.

Before each test fire, ventilate the room with clean air until it is free from smoke, so that the conditions given below can be obtained

Before beginning the test, ensure all ventilation systems are turned off and close all doors, windows, and openings Allow the air within the room to stabilize until the desired conditions are met, ensuring accurate and reliable test results.

5.22.2.5 Recording of the fire parameters and response values

During each test fire, it is essential to record the fire parameters listed in Table 4 as they change over time These parameters should be documented either continuously or at minimum once per second to ensure accurate data collection Proper recording of these parameters enables thorough analysis of fire behavior and performance, which is critical for optimizing safety and efficiency in testing procedures.

Parameter Symbol Unit temperature change ∆T °C smoke density (ionization) y (dimensionless) smoke density (optical) m dB/m carbon monoxide concentration S àl/l

The alarm signal given by the supply and monitoring equipment shall be taken as the indication that a specimen has responded to the test fire

Record the response time of each specimen's alarm signal, along with the parameters ∆T a, y a, m a, and S a, which represent the fire conditions at the moment of activation Responses occurring after the end-of-test condition should be disregarded to ensure accurate data collection.

All four specimens shall generate an alarm signal, in each test fire, before the specified end-of-test condition is reached

The test report must include key information such as the identification of the alarm tested, reference to ISO 7240-6:2011, and detailed test results, including individual response threshold values along with minimum, maximum, and average data where applicable It should also specify the conditioning period and atmosphere, as well as the temperature and relative humidity maintained in the test environment throughout the testing process Additionally, the report must provide details of the supply and monitoring equipment used, along with the alarm criteria, and document any deviations from ISO 7240-6:2011 or other relevant International Standards, including any optional operations performed during testing.

Gas test chamber for response threshold value and cross-sensitivity measurements

Key properties of the gas test chamber are essential for ensuring repeatable and reproducible measurements of fire detector response thresholds While not all influencing parameters can be specified or measured, it is crucial to consider the background information provided in Annex G when designing and utilizing the chamber Adhering to these guidelines ensures accurate and consistent testing in compliance with ISO 7240 standards.

The gas test chamber must feature a horizontal working section with a defined testing volume, where air temperature and airflow meet specified conditions Regular verification of the working volume’s conformity is essential, using measurements at multiple points within its boundaries under static conditions The volume should be sufficiently large to completely enclose the tested detector and sensing components of the measuring equipment The detector must be mounted in its normal operating position on a flat board aligned with the airflow, with the board dimensions ensuring at least 20 mm clearance from the detector edges Additionally, the mounting setup should not obstruct airflow between the board and the tunnel ceiling, ensuring accurate test conditions.

Essential means must be established to generate an essentially laminar airflow at the specified velocities of (0.2 ± 0.04) m/s or (1.0 ± 0.2) m/s within the working volume Additionally, the system should enable maintaining the temperature at designated levels and allow for temperature increases at a controlled rate not exceeding 1 K per minute, ensuring optimal environmental conditions for the application.

The response threshold of CO fire detectors is defined by the specific concentration of carbon monoxide in the air near the detector at the moment it activates an alarm Accurate gas concentration measurements, denoted as S, should be taken within the working volume surrounding the detector to ensure reliable detection.

Tiêu đề	Carbon monoxide fire detectors using electro-chemical cells
Trường học	International Organization for Standardization
Chuyên ngành	Fire detection and alarm systems
Thể loại	Tiêu chuẩn
Năm xuất bản	2011
Thành phố	Geneva

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