1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 14624:2012Performance of portableleak detectors and of roommonitors for halogenatedrefrigerantsBS EN 14624:2012 BRITISH STANDARDNational forewordThis British Standard is th
2、e UK implementation of EN 14624:2012. Itsupersedes BS EN 14624:2005 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee RHE/18, Refrigeration safety.A list of organizations represented on this committee can beobtained on request to its secretary.This public
3、ation does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2012ISBN 978 0 580 71695 9ICS 23.040.99; 71.100.45Compliance with a British Standard cannot confer immunity fromlegal obligations.This Brit
4、ish Standard was published under the authority of theStandards Policy and Strategy Committee on 31 January 2012.Amendments issued since publicationDate Text affectedBS EN 14624:2012EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 14624 January 2012 ICS 23.040.99; 71.100.45 Supersedes EN 14624:20
5、05English Version Performance of portable leak detectors and of room monitors for halogenated refrigerants Performances des dtecteurs de fuite portables et des contrleurs dambiance de fluides frigorignes halogns Leistung von mobilen Leckdetektoren und Raumberwachungsgerten fr halogenierte Kltemittel
6、 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 r
7、eferences 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
8、 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,
9、 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 COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management C
10、entre: 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: EBS EN 14624:2012EN 14624:2012 (E) 2 Contents Page Foreword 41 Scope 52 Normative references 53 Terms and definitions .54 Sym
11、bols 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 Sp
12、ecific 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 Specif
13、ic 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
14、.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 monitore
15、d 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
16、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
17、 15BS EN 14624:2012EN 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
18、 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 23BS EN 14624:2012EN 14624:2012 (E) 4 Foreword This document (EN 14624:2012) has been prepare
19、d 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,
20、 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. Thi
21、s 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
22、) 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, Cypru
23、s, 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. BS EN 14624:2012EN 14624:2012
24、(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
25、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
26、 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) full
27、y 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
28、/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
29、 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. BS EN 14624:2012EN 14624:2012 (E) 6 3.7 room monitor fixed device, with one or several sensors, permitting the indication or the measurement of co
30、ncentrations 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
31、 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 calib
32、ration 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
33、 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 m
34、onitor 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 (
35、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 s
36、et 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 BS EN 14624:2012EN 14624:2012 (E) 7 4 Symbols and abbreviations Table 1 Symbols and abbreviations Symbol Description Unit Vacc accumul
37、ation volume m3Vmol molar volume m3M molar mass g/mol m dynamic upper and lower detection limits for the alarm triggers of locating leak detectors. 13.2 Measuring leak detectors The product data sheet shall specify the following technical data: static upper and lower detection limits for the indicat
38、ion of concentrations or leakage rate values by measuring leak detectors; dynamic upper and lower detection limits for the indication of concentrations or leakage rate values by measuring leak detectors. 13.3 All portable leak detectors The product data sheet shall specify the following technical da
39、ta: response time; zeroing time; recovery time; lower detection limit in halogen gas contaminated environment; re-calibrating frequency; directions for use; safety instructions; leak detector weight. 13.4 Room monitor The product data sheet shall specify the following technical data for concentratio
40、n measurement: upper and lower detection limits; pre-set alarm point(s); response time to the lower alarm set point or measurement value specified e.g. 50 % full scale; response time to the upper alarm set point, if provided, or measurement value specified e.g. 90 % of full scale; recovery time; che
41、ck/calibration frequency as specified in 6.7; BS EN 14624:2012EN 14624:2012 (E) 17 installation instruction including guidelines for sensor locations in the room to be controlled; directions for use; safety instructions. BS EN 14624:2012EN 14624:2012 (E) 18 Annex A (informative) Conversion factors o
42、f leakage rate units Table A.1 Most common units y x Pa m3/s or W Torr l/s atm cm3/s mbar l/s 1 Pa m3/s or W 1 7,5 9,87 10 1 Torr l/s 0,133 1 1,32 1,33 1 atm cm3/s 0,101 3 0,76 1 1,013 1 mbar l/s 0,1 0,75 0,987 1 Table A.2 Other units Y X Pa m3/s lusec (micron 1/s) m ft3/s std cm3/s atm ft3/mn mol/s
43、 Pa m3/s 1 7,5 103 2,65 102 9,87 2,097 10-2 4,403 10-4 lusec (micron 1/s) 1,33 10-4 1 3,53 10-2 1,32 10-3 2,795 10-6 5,87 10-8 m ft3/s 3,76 10-3 2,83 10 1 3,71 10-2 7,92 10-5 1,662 10-6 std cm3/s 1,013 10-1 7,6 102 2,67 10 1 2,12 10-3 4,461 10-5 atm ft3/mn 4,78 10 3,58 105 1,264 104 4,72 102 1 2,105
44、 10-2 mol/s 2,271 103 1,703 107 6,016 105 2,24 104 47,49 1 BS EN 14624:2012EN 14624:2012 (E) 19 Annex B (informative) Correlation between test gas concentration and leakage rate EXAMPLE 1a Conversion of a concentration increase in a hood to a total leakage volume flow rate (pV-throughput) A test obj
45、ect pressurized with halogen gas should be tested for overall leakage. It is therefore placed in an envelope of given volume where the escaping halogen gas can accumulate for a definite period of time. After that time, the resulting concentration increase in the envelope measured with a leak detecto
46、r probe (by puncturing the envelope with the probe tip). The following assumptions are made: the envelope has a free volume (between test object and outer volume) V = 0,2 litre; the concentration increase is chalogen = 420 ppm; the accumulation time is tacc = 1 h; the pressure inside the envelope st
47、ays at atmospheric pressure patm = 1 000 mbar during the accumulation time (this means a soft envelope with pressure contact to the ambient atmosphere). The following equation yields the overall leakage rate as pV-throughput (volume flow rate): /sl mbar5102,3s 6003mbar 0001 420,000l0,2tatmhalogenhal
48、ogen =pcVpVq- The test object has a leakage rate of /sl mbar102,35 R-134a. Conclusion: To detect this leakage rate after 1 h accumulation time the leak detector has to be capable of measuring the assumed increase of refrigerant concentration of 420 ppm with good repeatability (its lower concentratio
49、n detection limit should be better than 100 ppm). (the conversion of this volume flow rate into a mass flow rate can be found in Example 2) EXAMPLE 1b Concentration increase due to a small leak in a voluminous room If measurement is carried out in a voluminous room and detection cells are placed at unknown pos
