SIST EN 14624:2012
(Main)Performance of portable leak detectors and of room monitors for halogenated refrigerants
Performance of portable leak detectors and of room monitors for halogenated refrigerants
The purpose of this European Standard is to qualify the performance of portable sniffing leak detectors and room monitors for halogenated refrigerants. These leak detectors are designed for the detection of CFC, HCFC, HFC and PFC halogenated gases, and their detection limit is checked with a calibration leak or calibration gas.
Leistung von mobilen Leckdetektoren und Raumüberwachungsgeräten für halogenierte Kältemittel
Diese Europäische Norm hat den Zweck, die Leistung von mobilen Schnüffel-Leckdetek¬toren und Raumüberwachungsgeräten für halogenierte Kältemittel zu bestimmen. Diese Leckdetektoren sind für den Nachweis von FCKW-, HFCKW-, HFKW- und FKW-Gasen bestimmt, ihre Nachweisgrenze wird mit einem Kalibrierleck oder Kalibriergas geprüft.
Performances des détecteurs de fuite portables et des contrôleurs d'ambiance de fluides frigorigènes halogènés
La présente Norme européenne a pour objet la définition des performances des détecteurs de fuite portables de type « renifleurs » et des contrôleurs d'ambiance des fluides halogénés. Ils sont conçus pour détecter des gaz halogénés de type CFC, HCFC, HFC et PFC, et leur limite de détection est vérifiée à l'aide d'une fuite d’étalonnage ou d'un gaz d’étalonnage.
Lastnosti premičnih javljalnikov puščanja in sobnih nadzornih naprav za halogenska hladila
Namen tega evropskega standarda je opredeliti lastnosti premičnih javljalnikov puščanja in sobnih nadzornih naprav za halogenska hladila. Ti javljalniki puščanja so izdelani za zaznavanje halogenskih plinov CFC, HCFC, HFC in PFC, pri čemer se meja zaznavanja preveri s kalibracijskim puščanjem ali kalibracijskim plinom.
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Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Leistung von mobilen Leckdetektoren und Raumüberwachungsgeräten für halogenierte KältemittelPerformances des détecteurs de fuite portables et des contrôleurs d'ambiance de fluides frigorigènes halogènésPerformance of portable leak detectors and of room monitors for halogenated refrigerants71.100.45Hladiva in antifriziRefrigerants and antifreezes27.200Hladilna tehnologijaRefrigerating technologyICS:Ta slovenski standard je istoveten z:EN 14624:2012SIST EN 14624:2012en,fr,de01-marec-2012SIST EN 14624:2012SLOVENSKI
STANDARDSIST EN 14624:20051DGRPHãþD
SIST EN 14624:2012
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 14624
January 2012 ICS 23.040.99; 71.100.45 Supersedes EN 14624:2005English Version
Performance of portable leak detectors and of room monitors for halogenated refrigerants
Performances des détecteurs de fuite portables et des contrôleurs d'ambiance de fluides frigorigènes halogénés
Leistung von mobilen Leckdetektoren und Raumüberwachungsgeräten für halogenierte Kältemittel This European Standard was approved by CEN on 19 November 2011.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre:
Avenue Marnix 17,
B-1000 Brussels © 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 14624:2012: ESIST EN 14624:2012
EN 14624:2012 (E) 2 Contents Page Foreword .41 Scope .52 Normative references .53 Terms and definitions .54 Symbols and abbreviations .75 Types of portable leak detectors and room monitors .76 General requirements for all portable leak detectors and room monitors .76.1 Gas type .76.2 Capabilities .76.3 Output signal .86.4 Response time .86.5 Recovery time (clean up time) .86.6 Repeatability .86.7 Calibration .87 Specific requirements for locating portable leak detectors .87.1 General .87.2 Lowest detectable leakage rate threshold when the leak detector is stationary .97.3 Lowest detectable leakage rate threshold value when the detector probe is moving .97.4 Leak detection in a contaminated environment .98 Specific requirements for room monitors . 108.1 General . 108.2 Lowest detectable concentration (lower detection limit) . 108.3 Highest tolerable concentration (upper detection limit) . 108.4 Upper and lower alarm thresholds . 108.5 Response time for alarm trigger . 109 Calibration leaks . 109.1 General . 109.2 Calibration gases . 1010 Test apparatus . 1110.1 General . 1110.2 Apparatus no. 1: detector probe stationary at the orifice of a calibration leak . 1110.3 Apparatus no. 2: detector probe moved with defined speed and distance in front of a calibration leak . 1110.4 Apparatus no. 3: Chamber with monitored concentration . 1211 Performance tests. 1211.1 Performance test of locating leak detector . 1211.1.1 Test no. 1: Static detection . 1211.1.2 Test no. 2: dynamic detection limit . 1311.1.3 Test no. 3: detection limit in contaminated environment . 1311.1.4 Test no. 4: recovery time . 1311.2 Performance tests of room monitor . 1311.2.1 General . 1311.2.2 Test a) to determine the upper and lower detection limits . 1311.2.3 Test b) to determine response time . 1411.2.4 Test c) to determine recovery time from exposure to a large concentration . 1412 Instrument characteristics and reporting of test results . 15SIST EN 14624:2012
EN 14624:2012 (E) 3 12.1 Characteristics of locating leak detector . 1512.2 Characteristics of room monitors . 1513 Technical data . 1613.1 Locating leak detectors . 1613.2 Measuring leak detectors . 1613.3 All portable leak detectors. 1613.4 Room monitor . 16Annex A (informative)
Conversion factors of leakage rate units . 18Annex B (informative)
Correlation between test gas concentration and leakage rate . 19Annex C (informative)
Guidelines for monitoring a machinery room or space for gas leaks . 23 SIST EN 14624:2012
EN 14624:2012 (E) 4 Foreword This document (EN 14624:2012) has been prepared by Technical Committee CEN/TC "Refrigerating systems, safety and environmental requirements ", the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by July 2012, and conflicting national standards shall be withdrawn at the latest by July 2012. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 14624:2005. The following changes have been made during revision: a) Clause 3 "Terms and definitions" has been revised; b) Clause 11 "Performance tests" has been completely revised; c) Annex B "Correlation between test gas concentration and leakage rate" has been modified; d) Annex C "Guideline for monitoring a machinery room or space for gas leaks" has been included. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. SIST EN 14624:2012
EN 14624:2012 (E) 5 1 Scope The purpose of this European Standard is to qualify the performance of portable sniffing leak detectors and room monitors for halogenated refrigerants. These leak detectors are designed for the detection of CFC, HCFC, HFC and PFC halogenated gases, and their detection limit is checked with a calibration leak or calibration gas. 2 Normative references Not applicable. 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 chloro-fluoro-carbon (CFC) fully halogenated halocarbon composed only of chlorine, fluorine and carbon NOTE The hydrogen is completely substituted. 3.2 hydro-chloro-fluoro-carbon (HCFC) partly halogenated halocarbon composed only of hydrogen, chlorine, fluorine and carbon 3.3 hydro-fluoro-carbon (HFC) partly fluorinated halocarbon composed only of hydrogen, fluorine and carbon 3.4 perfluoro-carbon (PFC) fully fluorinated halocarbon composed only of fluorine and carbon NOTE
The hydrogen is completely substituted. 3.5 gas concentration ratio in weight or in volume of a given gas to the total weight or volume of the gas mixture NOTE 1 The concentration is dimensionless and is designated either with ppm (m/m) = parts per million (mass) or
ppm (V/V) = parts per million (volume). NOTE 2 ppm: statement of concentration for gases; parts per million expressed in volume per volume ratio. 3.6 leakage rate gas flow through a fissure, an orifice or aperture of specified size NOTE 1 The usual leakage rate unit is gram per year (g/a), see Annex A (informative). NOTE 2 The gas flow channels are some micrometers of diameter and have a large length/diameter ratio. SIST EN 14624:2012
EN 14624:2012 (E) 6 3.7 room monitor fixed device, with one or several sensors, permitting the indication or the measurement of concentrations of halogen gases in the atmosphere at one or several points in one room or in several rooms 3.8 locating leak detector either indicating or measuring portable leak detector with a detector probe capable of localizing a leak by measuring a local gas concentration with short response time 3.9 indicating leak detector leak detector indicating one or several levels of concentration or leakage rate thresholds, but with no indication of the measured value 3.10 measuring leak detector leak detector that measures leakage rates or concentrations and displays the respective value 3.11 calibration leak device with a defined flow rate of a given gas under defined pressure and temperature conditions used to calibrate a leak detector NOTE Calibration leaks are themselves calibrated according to operation conditions (upstream and downstream pressure) against a primary or secondary standard that is traceable to national standards (standard leak). 3.12 response time time elapsing from the moment the probe is placed into a concentration or exposed to a calibration gas or in front of a leak until an alarm is triggered 3.13 recovery time time required for a leak detection system or room monitor to indicate the lower detection limit again after exposure to a specified large leakage rate or concentration without any manual zeroing operation 3.14 zeroing time (for leak detectors) time from immersion of the probe into a fixed concentration of halogen gas until indicated zero is stable (automatically or after a zeroing action specified by the manufacturer) 3.15 detection limit (lower, upper) minimum or maximum detectable concentration or leakage rate which can be indicated with specified uncertainty and/or for which an alarm level can be set and is repeatedly triggered 3.16 alarm set points one or more preset alarm set points/thresholds at which an alarm level(s) can be set and which can be repeatedly triggered by the appropriate concentration
SIST EN 14624:2012
EN 14624:2012 (E) 7 4 Symbols and abbreviations Table 1 — Symbols and abbreviations Symbol Description Unit Vacc accumulation volume m3 Vmol molar volume m3 M molar mass g/mol m& mass flow kg/s or g/a ν& molar mass flow rate mol/s pVq& Leakage rate (pV-throughput) mbar - l/s or Pa - m3/s C Concentration V/V or m/m
5 Types of portable leak detectors and room monitors The types of detectors shown in Table 2 are concerned in this European Standard: Table 2 — Types of detectors
IndicatingMeasuring Room monitor A B Locating leak detector
C D
Both the indicating leak detector and room monitor can be designed with thresholds: either one fixed threshold which is not adjustable or several fixed or adjustable thresholds. Both the measuring leak detector and the room monitor comprise a scale and permit assigning of a measurement value to a gas concentration in the atmosphere. 6 General requirements for all portable leak detectors and room monitors 6.1 Gas type The manufacturer shall specify the gas or the gas(es) that the leak detector is able to detect or measure. 6.2 Capabilities Locating leak detectors or room monitors are single-gas or multi-gas measuring devices. They are selective or non-selective and shall be able to measure or indicate a concentration or leakage rate threshold of halogen gas. Selective locating detectors or room monitors shall be able to identify a specific halogen gas among other gases. Non-selective locating detectors or room monitors cannot identify a specific halogen gas among other gases but they shall detect all halogen gases present in a gas mixture as a sum value. SIST EN 14624:2012
EN 14624:2012 (E) 8 6.3 Output signal The indication or the measurement mode of the leak detector can be instantaneous or continuous and shall generate a signal (audible and/or visual) to indicate that a pre-set alarm level is exceeded (the signal alerts operators in charge of the leak tightness inspection or responsible for the supervision of the system charged with halogen gas). 6.4 Response time The manufacturer shall specify the response time for the output signal. 6.5 Recovery time (clean up time) The manufacturer shall specify the recovery time after the portable leak detector probe has been indicating the leakage rate of the largest refrigerant leak (upper detection limit). 6.6 Repeatability For identical concentration values of a defined halogen gas, the leak detector or the room monitor shall give identical readings at repeated measurements within an uncertainty range specified by the manufacturer. 6.7 Calibration Checks/calibration, at least annually, shall be carried out in accordance with the manufacturer recommendations. For portable leak detectors a calibration leak shall be used. In the case of room monitors, a calibration gas shall be used. Local regulations or standards may specify the frequency or nature of this check. 7 Specific requirements for locating portable leak detectors 7.1 General Locating leak detectors shall be able to indicate a halogen leak in two different situations: first, when the detector probe is stationary in front of a leak, second, when the detector probe is moving in front of a leak.
SIST EN 14624:2012
EN 14624:2012 (E) 9
Key
1 sniffer probe
2 test object with leak
d sniffing distance
a) Sniffing distance d during leak search on a test object
Key
1 sniffer probe
3 calibration leak outlet
d sniffing distance
b) Sniffing distance d during calibration with a calibration leak Figure 1 — Sniffing distance
7.2 Lowest detectable leakage rate threshold when the leak detector is stationary The leak detector with the probe held stationary in front of a leak at a distance of 3 mm shall give a visual or acoustical alarm indicating that the threshold value set equal to the leakage rate value has been exceeded. Testing conditions are detailed in 11.1. 7.3 Lowest detectable leakage rate threshold value when the detector probe is moving The detector probe, when moved across a leak passing at a speed of 2 cm/s and a distance of 3 mm in front of the leak exit, shall be able to repeatedly detect this leakage rate. Testing conditions are detailed in 11.1. 7.4 Leak detection in a contaminated environment The leak detector shall be able to compensate for a slowly varying contaminating concentration of the halogen refrigerant and retain its detection ability for leak location. SIST EN 14624:2012
EN 14624:2012 (E) 10 8 Specific requirements for room monitors 8.1 General Room monitors can be single-sensor or multi-sensor instruments. Requirements shall be verified for each sensor. 8.2 Lowest detectable concentration (lower detection limit) The manufacturer shall specify the lowest detectable concentration in parts per million (ppm). 8.3 Highest tolerable concentration (upper detection limit) The manufacturer shall specify the highest detectable concentration in parts per million (ppm) (this is the critical concentration which prevents the cell from recovering to its initial detection limit). 8.4 Upper and lower alarm thresholds The manufacturer shall specify the method to set upper and lower alarm thresholds, and the way the user can check them. 8.5 Response time for alarm trigger The manufacturer shall specify the response time. 9 Calibration leaks 9.1 General Two types of calibration leaks exist and are commercially available: capillary calibration leaks and membrane calibration leaks (permeation membrane). Industrial calibration leaks permit to verify the correct operation of on-site leak detectors. Industrial membrane or capillary calibration leaks shall be re-calibrated after a time recommended by the manufacturer. The accuracy of calibration leaks shall be specified by the manufacturer by a statement of uncertainty of the nominal leakage rate. Industrial calibration leaks shall be calibrated with reference to secondary standards, which can also be calibration leaks. These secondary standards are calibrated with reference to a primary standard made available by the respective national metrological institute. Secondary standards: leaks calibrated with reference to the primary standard are used for the calibration of industrial calibration leaks and for the qualification of leak detectors in the test apparatus described in Clause 10. 9.2 Calibration gases A calibration gas consists of the target gas at a specified concentration e.g. R404A at 1000 ppm, in a carrier gas such as air or nitrogen and at a specified concentration uncertainty. Calibration gases are readily available in cylinders or may be produced in test chambers by injection of the target gas by syringe or by the use of calibrated mass flow controllers or equivalent. SIST EN 14624:2012
EN 14624:2012 (E) 11 10 Test apparatus 10.1 General R-134a is the reference refrigerant for measurements described in the following procedures. R-25 and R-32 are used for selectivity tests. 10.2 Apparatus no. 1: detector probe stationary at the orifice of a calibration leak The apparatus comprises a calibration leak that is a secondary standard with ± 15 % uncertainty of its value. The apparatus is located in a room where ambient temperature is (20 to 25) °C and relative humidity
(30 to 70) % at atmospheric pressure. The alarm threshold of the leak detector is set to the nominal leakage rate value of the calibration leak in the test device. 10.3 Apparatus no. 2: detector probe moved with defined speed and distance in front of a calibration leak The apparatus comprises a calibration leak that is a secondary standard with uncertainty of ± 15 % of its value. The detector probe is located on a sliding carriage or pivoting arm which can be moved from left to right and vice-versa in front of the leak exit at a speed adjustable between 1 cm/s and 3 cm/s, the distance adjustable in the range of 1 mm to 5 mm with a minimum deflection of approximately 10 cm (the dwell time offside the leak shall at least be equal to the recovery time). The apparatus, see Figure 2, is located in a room where ambient temperature is (20 to 25) °C and relative humidity (30 to 70) % at atmospheric pressure. The alarm threshold of the leak detector is set to the nominal leakage rate value of the calibration leak in the test device. SIST EN 14624:2012
EN 14624:2012 (E) 12
Key
Key 1 calibration leak 1 calibration leak 2 leak detector probe 2 leak detector probe 3 base plate 3 base plate 4 leak detector 4 leak detector 5 sliding carriage with variable speed 5 pivoting arm with variable speed 6 driving system of the sliding carriage 6 driving system of the pivoting arm 7 minimum distance between the calibration leak
7 minimum distance between the
exit and the sensor probe tip
calibration leak exit and the sensor
a) — Apparatus no. 2: test stand with
b) — Apparatus no. 2: test stand sliding leak detector probe with pivoting leak detector probe
Figure 2 — Apparatus no. 2 10.4 Apparatus no. 3: Chamber with monitored concentration A definite concentration of R-134a vapour is generated by a gas mixing device or e.g. by injection of a definite volume of R-134a with a syringe into a tight chamber of known volume containing synthetic air. To obtain a uniform concentration in the chamber the gas is mixed with a fan, which is switched off before every measurement. 11 Performance tests 11.1 Performance test of locating leak detector 11.1.1 Test no. 1: Static detection 11.1.1.1 Detection limit The locating leak detector probe is placed at a distance of 3 mm ± 0,5 mm in front of the calibration leak of apparatus no. 1 during no longer than 10 s and the minimum leakage rate for triggering a respective alarm is determined. This test is repeated for various nominal values of leakage rates: 10 g/a, 5 g/a and 3 g/a until the detection limit is established. The leaks may have actual leakage rate values within ± 20 % of the above nominal values.
SIST EN 14624:2012
EN 14624:2012 (E) 13 11.1.1.2 Leak detector response time After each test, the leak detector is placed in clean ambient air and the response time (see 6.4) is measured. The test is repeated 10 times for each value of calibration leakage rate, and the readings given by the leak detector are recorded. The indication can be either an audible or visual alarm or a reading if the system is a measuring leak detector. 11.1.1.3 Cross-sensitivity The test for detection limit is repeated with the interfering gases R-125 and R-32 at the minimum leakage rate or concentration threshold measured previously. The leak detector’s reading for the interfering gases is recorded. 11.1.2 Test no. 2: dynamic detection limit The leak detector probe is placed on apparatus no. 2 at a distance of 3 mm ± 0,5 mm moving at a speed of 1scm0,2)(2−±. The leak detector signal is recorded during each passage in front of the leak orifice. The dynamic detection limit test is repeated 10 times in a sequence and the output signal is recorded each time. This test is repeated for various nominal values of leakage rates: 10 g/a, 5 g/a and 3 g/a until the detection limit is established. The leaks used may have values within ± 20 % of the above nominal values. 11.1.3 Test no. 3: detection limit in contaminated environment The apparatus no. 2 is placed in a chamber (apparatus no. 3) where the concentration of halogen refrigerant is the maximum concentration in ppm as specified by the manufacturer. In the absence of such a specification the maximum concentration shall be 1000 ppm. A tolerance of ± 10 % of the concentration is acceptable. The leak detector probe is located in the same chamber, the zeroing procedure of the leak detector as recommended by the manufacturer is applied and the dynamic detection limit is measured according to the same procedure as test no. 2. 11.1.4 Test no. 4: recovery time The leak detector probe is placed in front of the largest leak as specified by the manufacturer for 10 s. If not specified by the manufacturer this leak shall be 50 g/a. The probe is then removed from the large leak and placed again in front of the apparatus no. 1 with the alarm trigger set to the detection limit. The recovery time is measured. This test is repeated five times. 11.2 Performance tests of room monitor 11.2.1 General These tests are carried out in a room at atmospheric pressure where ambient temperature is (20 to 25) °C and relative humidity (30 to 70) %. 11.2.2 Test a) to determine the upper and lower detection limits Each sensor of the room monitor is located in the test chamber (apparatus no. 3) or alternatively, without a chamber, calibration gas (± 5 % concentration uncertainty) may be delivered directly to each sensor in turn using a typical calibration kit as shown in Figure 3. SIST EN 14624:2012
EN 14624:2012 (E) 14
Key 1 cylinder typically 44 cm high 110 l capacity of calibration gas 2 flow regulator typical flow 0,3 l/min 3 flexible non-absorbant tubing 4 vented calibration hood Figure 3 — Calibration kit Concentrations of 10 ppm, 20 ppm, 50 ppm, 100 ppm, 1000 ppm and intermediate or higher values if the manufacturer so requires, are generated successively in the test chamber (by injection of the required gas volume with a syringe or using a calibrated mass flow controller) or delivered to the sensor using calibration gases. The upper and lower detection limits shall be established and recorded. 11.2.3 Test b) to determine response time The alarm set points, one or more e.g. 100 ppm or 500 ppm, are specified by the manufacturer. Each sensor of the room monitor is located in the test apparatus chamber (apparatus no. 3) or alternatively, without a chamber, calibration gas may be delivered directly to each sensor in turn using a typical calibration kit. The concentrations specified in turn (if more than one) are generated successively in the test chamber (by injection of the required gas volume with a syringe or using calibrated mass flow controllers) or delivered directly to the sensor using calibration gases. The time to reach the alarm set point(s) or in the case of an indicating controller the time to display the specified values e.g. 50 % or 90 % of full scale is recorded. 11.2
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