IEC TR 60695-2-22:2026

IEC TR 60695-2-22 ®
Edition 1.0 2026-03
TECHNICAL
REPORT
HORIZONTAL PUBLICATION
BASIC SAFETY PUBLICATION
Fire hazard testing -
Part 2-22: Glowing/hot-wire based test methods - Results of the round robin
tests for the development of IEC TS 60695-2-21:2023
ICS 13.220.40; 29.020  ISBN 978-2-8327-1159-0

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CONTENTS
FOREWORD . 9
INTRODUCTION . 11
1 Scope . 12
2 Normative references . 12
3 Terms, definitions, and abbreviated terms . 12
3.1 Terms and definitions. 12
3.2 Abbreviated terms . 13
4 General information . 13
4.1 Information on round robin tests . 13
4.2 Information on participants . 13
5 First round robin test . 14
5.1 First round robin test objectives . 14
5.2 First round robin test equipment. 15
5.3 First round robin test participants . 15
5.4 First round robin test summary of tests . 15
5.5 First round robin test summary of activities setup. 16
5.6 First round robin test results . 17
5.6.1 First RRT apparatus and test conditions . 17
5.6.2 First RRT NiCr wire cuts resistance verification . 18
5.6.3 First RRT Verification of achieved ignitions . 19
5.6.4 First RRT Verification of connectors time to ignition . 29
5.6.5 First RRT Verification of connectors flame duration . 37
5.6.6 First RRT Verification of connector flame heights . 46
5.6.7 First RRT NiCr wire cuts burnouts during tests . 50
5.7 First round robin test outcome . 56
5.7.1 Connectors ignition and NiCr wire application method . 56
5.7.2 Enclosures testing repeatability . 56
5.7.3 Conclusions . 56
6 Second round robin test. 57
6.1 Second round robin test objectives . 57
6.2 Second round robin test equipment . 57
6.3 Second round robin test participants . 58
6.4 Second round robin test summary of tests . 58
6.5 Second round robin test summary of activities setup . 58
6.6 Second round robin test results. 59
6.6.1 Second RRT apparatus and test conditions . 59
6.6.2 Second RRT NiCr wire cuts resistance verification . 60
6.6.3 Second RRT verification of achieved ignitions . 62
6.6.4 Second RRT Verification of connector time to ignition . 69
6.6.5 Second RRT Verification of connector flame duration . 71
6.6.6 Second RRT verification of connector flame height . 73
6.7 Second round robin test outcome . 74
6.7.1 NiCr wire cuts resistance comparison . 74
6.7.2 Connectors testing results comparison . 75
6.7.3 Finished units testing results comparison . 76
6.7.4 Conclusions . 77
7 Third round robin test . 77
7.1 Third round robin test objectives . 77
7.2 Third round robin test equipment . 78
7.3 Third round robin test participants . 78
7.4 Third round robin test summary of tests . 79
7.5 Third round robin test summary of activities setup . 79
7.6 Third round robin test results . 81
7.6.1 Third RRT Verification of achieved ignitions . 81
7.6.2 Third RRT Verification of time to ignition . 87
7.6.3 Third RRT Verification of connectors flame duration . 98
7.7 Third round robin test outcome . 102
7.7.1 External NiCr wire application method and NiCr wire length over 100 mm . 102
7.7.2 Uninsulated connectors testing effectiveness. 104
8 Round robin test results analysis . 104
8.1 General . 104
8.2 Plastic insulating connectors achieved ignitions . 105
8.3 Plastic insulating connectors time to ignitions . 105
8.4 Plastic insulating connectors flame durations . 106
8.5 Finished unit enclosures achieved ignitions . 107
9 Document conclusion . 108
Annex A (informative) Examples of the round robin tests . 109
A.1 First RRT tests examples . 109
A.2 Second RRT examples . 110
A.3 Third RRT examples . 113
Bibliography . 115

Figure 1 – First RRT - NiCr wire resistance measurements . 19
Figure 2 – First RRT - Bench test V2 connector with internal NiCr wire - Time to
ignition . 30
Figure 3 – First RRT - Bench test V0 connector with internal NiCr wire - Time to
ignition . 31
Figure 4 – First RRT - Enclosure test V2 connector with internal NiCr wire - Time to
ignition . 34
Figure 5 – First RRT - Enclosure test V2 connector with external NiCr wire - Time to
ignition . 35
Figure 6 – First RRT - Enclosure test V0 connector with internal NiCr wire - Time to
ignition . 36
Figure 7 – First RRT - Bench test V2 connector with internal NiCr wire - Flame duration . 38
Figure 8 – First RRT - Bench test V0 connector with internal NiCr wire - Flame duration . 40
Figure 9 – First RRT - Enclosure test V2 connector with internal NiCr wire - Flame
duration . 42
Figure 10 – First RRT - Enclosure test V2 connector with external NiCr wire - Flame
duration . 43
Figure 11 – First RRT - Enclosure test V0 connector with internal NiCr wire - Flame
duration . 44
Figure 12 – First RRT - Bench test V2 connector with internal NiCr wire - Flame height . 47
Figure 13 – First RRT - Bench test of V0 connector with internal NiCr wire - Flame
height . 48
Figure 14 – Second RRT - NiCr wire resistance measurements . 61
Figure 15 – Second RRT - Bench test of V2 Connectors with internal NiCr wire -
Connector time to ignition . 70
Figure 16 – Second RRT - Bench test of V2 Connectors with internal NiCr wire -
Connector flame duration . 72
Figure 17 – Second RRT - Bench test of V2 Connectors with internal NiCr wire -
Connector flame height . 74
Figure 18 – Third RRT - V2 Connectors time to ignition . 88
Figure 19 – Third RRT - V0 Connectors time to ignition . 89
Figure 20 – Third RRT - Top specified layer time to ignition - V2 Connectors with top
plastic sheet HB results . 90
Figure 21 – Third RRT - Top specified layer time to ignition - V0 Connectors with top
plastic sheet HB results . 91
Figure 22 – Third RRT - Top specified layer time to ignition -Uninsulated connectors
with top plastic sheet HB results . 92
Figure 23 – Third RRT - Top specified layer time to ignition -Uninsulated connectors
with top plastic sheet V0 results . 93
Figure 24 – Third RRT - Lower specified layer time to ignition - V2 Connectors results . 95
Figure 25 – Third RRT - Top specified layer time to ignition -Uninsulated connectors
with top plastic sheet HB results . 96
Figure 26 – Third RRT - Top specified layer time to ignition - V2 connectors with top
plastic sheet HB results . 97
Figure 27 – Third RRT - Top specified layer time to ignition - V0 connectors with top
plastic sheet HB results . 98
Figure 28 – Third RRT – V2 Connectors flame duration . 99
Figure 29 – Third RRT - V0 Connectors flame duration . 100
Figure 30 – Third RRT - Flame duration - Finished units test of V2 Connectors with top
plastic sheet HB . 101
Figure 31 – Third RRT - Flame duration - Finished units test of V0 Connectors with top
plastic sheet HB . 102
Figure A.1 – First RRT - Example of plastic insulating connector with internal NiCr wire
coil - bench test . 109
Figure A.2 – Example of plastic insulating connector with internal NiCr wire coil -
Finished unit test . 110
Figure A.3 – Second RRT - Example of plastic insulating connector with internal NiCr
wire coil - bench test . 111
Figure A.4 – Second RRT - Example of plastic insulating connector with internal NiCr
wire coil - Finished unit 1 test . 112
Figure A.5 – Second RRT - Example of plastic insulating connector with internal NiCr
wire coil - Finished unit 2 test . 113
Figure A.6 – Third RRT - Example of plastic insulating connector with external NiCr
wire coil - bench test . 113
Figure A.7 – Third RRT - Example of simulated finished unit test by uninsulated
connector with external NiCr wire coil . 114
Figure A.8 – Third RRT - Example of simulated finished unit test by plastic insulated
connector with external NiCr wire coil . 114

Table 1 – Summary of round robin test participants . 14
Table 2 – First RRT - Objectives and verification methods . 14
Table 3 – First RRT - Participants . 15
Table 4 – First RRT - Investigation points and related subclause references . 15
Table 5 – First RRT - Tests list . 16
Table 6 – First RRT - Participants' apparatus and test conditions. 17
Table 7 – First RRT - NiCr wire cuts resistance measurements . 18
Table 8 – First RRT - Bench test of V2 connectors with internal NiCr wire - Connector
ignition verification results . 20
Table 9 – First RRT - Bench test of V2 connectors with external NiCr wire - Connector
ignition verification results . 20
Table 10 – First RRT - Bench test of V0 Connectors with internal NiCr wire - Connector
ignition verification results . 21
Table 11 – First RRT - Bench test of V0 connectors with external NiCr wire - Connector
ignition verification results . 21
Table 12 – First RRT - Summary of bench tests - Connectors achieved ignitions results . 22
Table 13 – First RRT - Enclosure test of V2 connectors with internal NiCr wire -
Connector ignition verification results . 23
Table 14 – First RRT - Enclosure test of V2 connectors with external NiCr wire -
Connector ignition verification results . 23
Table 15 – First RRT - Enclosure test of V0 connectors with internal NiCr wire -
Connector ignition verification results . 24
Table 16 – First RRT - Enclosure test of V0 connectors with external NiCr wire -
Connector ignition verification results . 24
Table 17 – First RRT - Summary of enclosure test - Connectors achieved ignitions
results . 25
Table 18 – First RRT - Enclosure test by V2 connectors with internal NiCr wire -
Enclosure ignition verification results . 26
Table 19 – First RRT - Enclosure test by V2 connectors with external NiCr wire -
Enclosure ignition verification results . 27
Table 20 – First RRT - Enclosure test by V0 connectors with internal NiCr wire -
Enclosure ignition verification results . 27
Table 21 – First RRT - Enclosure test by V0 connectors with external NiCr wire -
Enclosure ignition verification results . 28
Table 22 – First round robin results - Summary of enclosure tests - Enclosure achieved
ignitions results. 29
Table 23 – First RRT - Bench test of V2 connectors with internal NiCr wire - Connector
time to ignition verification results . 29
Table 24 – First RRT - Bench test of V2 connectors with external NiCr wire - Connector
time to ignition verification results . 30
Table 25 – First RRT - Bench test of V0 connectors with internal NiCr wire - Connector
time to ignition verification results . 31
Table 26 – First RRT - Bench test of V0 connectors with external NiCr wire - Connector
time to ignition verification results . 32
Table 27 – First RRT - Summary of bench tests - Connectors time to ignitions results . 32
Table 28 – First RRT - Enclosure test of V2 connectors with internal NiCr wire -
Connector time to ignition verification results . 33
Table 29 – First RRT - Enclosure test of V2 connectors with external NiCr wire -
Connector time to ignition verification results . 34
Table 30 – First RRT - Enclosure test of V0 connectors with internal NiCr wire -
Connector time to ignition verification results . 35
Table 31 – First RRT - Enclosure test of V0 connectors with external NiCr wire -
Connector time to ignition verification results . 36
Table 32 – First round robin results - Summary of enclosure tests - Connectors time to
ignitions results. 37
Table 33 – First RRT - Bench test of V2 connectors with internal NiCr wire - Connector
flame duration verification results . 38
Table 34 – First RRT - Bench test of V2 connectors with external NiCr wire - Connector
flame duration verification . 39
Table 35 – First RRT - Bench test of V0 ocnnectors with internal NiCr wire - Connector
flame duration verification . 39
Table 36 – First RRT - Bench test of V0 ocnnectors with external NiCr wire - Connector
flame duration verification . 40
Table 37 – First RRT - Summary of bench test - Connector flame duration . 41
Table 38 – First RRT - Enclosure test of V2 connectors with internal NiCr wire -
Connector flame duration verification . 41
Table 39 – First RRT - Enclosure test of V2 connectors with external NiCr wire -
Connector flame duration verification . 42
Table 40 – First RRT - Enclosure test of V0 connectors with internal NiCr wire -
Connector flame duration verification . 43
Table 41 – First RRT - Enclosure test of V0 connectors with external NiCr wire -
Connector flame duration verification . 44
Table 42 – First RRT - Summary of enclosure test - Connector flame duration . 45
Table 43 – First RRT - Bench test of V2 connectors with internal NiCr wire - Connector
flame height verification . 46
Table 44 – First RRT - Bench test of V2 connectors with internal NiCr wire - Connector
flame height verification . 47
Table 45 – First RRT - Bench test of V0 connectors with internal NiCr wire - Connector
flame height verification . 48
Table 46 – First RRT - Bench test of V0 connectors with external NiCr wire - Connector
flame height verification . 49
Table 47 – First Round Robin Results - Summary of bench test - Connector flame
height . 49
Table 48 – First RRT - Bench test of V2 connectors with internal NiCr wire - NiCr wire
burnouts . 50
Table 49 – First RRT - Bench test of V2 connectors with external NiCr wire - NiCr wire
burnouts . 51
Table 50 – First RRT - Bench test of V0 connectors with internal NiCr wire - NiCr wire
burnouts . 51
Table 51 – First RRT - Summary of the NiCr wire burnouts verifications during plastic
insulating connector bench tests . 52
Table 52 – First RRT - Summary of NiCr wire burnout verifications during plastic
insulating connector bench tests . 52
Table 53 – First RRT - Enclosure test of V2 Connectors with internal NiCr wire - NiCr
wire burnouts . 53
Table 54 – First RRT - Enclosure test of V2 Connectors with external NiCr wire - NiCr
wire burnouts . 53
Table 55 – First RRT - Enclosure test of V0 Connectors with internal NiCr wire - NiCr
wire burnouts . 54
Table 56 – First RRT - Enclosure test of V0 Connectors with external NiCr wire - NiCr
wire burnouts . 55
Table 57 – First RRT - Enclosure test of V0 Connectors with external NiCr wire - NiCr
wire burnouts . 55
Table 58 – First RRT - Summary of connector ignition results . 56
Table 59 – Second round robin test - Objectives and verification methods . 57
Table 60 – Second RRT - Participants . 58
Table 61 – Second RRT - Investigation points and related subclause references . 58
Table 62 – Second RRT - Tests list. 59
Table 63 – Second RRT - Test equipment and environmental conditions . 60
Table 64 – Second RRT - NiCr wire cuts resistance measurements . 61
Table 65 – Second RRT - Summary of verification of achieved ignitions . 62
Table 66 – Second RRT - Bench test of V2 Connectors with internal NiCr wire -
Connector ignition verification results . 63
Table 67 – Second RRT - Bench test of V0 Connectors with internal NiCr wire -
Connector ignition verification results . 63
Table 68 – Second RRT - Finished unit 1 test with V2 Connectors with internal NiCr
wire - Finished unit enclosure ignition verification results . 64
Table 69 – Second RRT - Finished unit 1 test with V0 Connectors with internal NiCr
wire - Finished unit enclosure ignition verification results . 65
Table 70 – Second RRT - Finished unit 2 test with V2 Connectors with internal NiCr
wire - Finished unit enclosure ignition verification results . 65
Table 71 – Second RRT - Finished unit 2 test with V0 Connectors with internal NiCr
wire - Finished unit enclosure ignition verification results . 66
Table 72 – Second RRT - Finished unit 1 test with V2 Connectors with internal NiCr
wire - Specified layer ignition verification results . 67
Table 73 – Second RRT - Finished unit 1 test with V0 Connectors with internal NiCr
wire - Specified layer ignition verification results . 67
Table 74 – Second RRT - Finished unit 2 test with V2 Connectors with internal NiCr
wire - Specified layer ignition verification results . 68
Table 75 – Second RRT - Finished unit 2 test with V0 Connectors with internal NiCr
wire - Specified layer ignition verification results . 69
Table 76 – Second RRT - Bench test of V2 Connectors with internal NiCr wire -
Connector time to ignition verification results . 69
Table 77 – Second RRT - Bench test of V0 Connectors with internal NiCr wire -
Connector time to ignition verification results . 71
Table 78 – Second RRT - Bench test of V2 Connectors with internal NiCr wire -
Connector flame . 71
Table 79 – Second RRT - Bench test of V0 Connectors with internal NiCr wire -
Connector flame duration . 72
Table 80 – Second RRT - Bench test of V2 Connectors with internal NiCr wire -
Connector flame height . 73
Table 81 – Second RRT - Bench test of V0 Connectors with internal NiCr wire -
Connector flame height . 74
Table 82 – Second RRT - Outcome of NiCr wire cuts resistance . 75
Table 83 – Second RRT - Outcome of connectors achieved ignition. 75
Table 84 – Second RRT - Outcome of connectors time to ignition . 75
Table 85 – Second RRT - Outcome of connectors flame duration. 76
Table 86 – Second RRT - Outcome of connectors flame height . 76
Table 87 – Second RRT - Outcome of finished units ignition . 76
Table 88 – Third RRT - Objectives and verification methods . 77
Table 89 – Third RRT - Participants . 79
Table 90 – Third RRT - Investigation points and related subclause references . 79
Table 91 – Third RRT - Tests list . 79
Table 92 – Third RRT - Bench test of V2 Connectors with external NiCr wire - Ignitions
verification . 81
Table 93 – Third RRT - Bench test of V0 Connectors with external NiCr wire - Ignitions
verification . 82
Table 94 – Third RRT - Uninsulated connector test of finished unit with V0 plastic
sheet - Ignitions verification . 83
Table 95 – Third RRT - Uninsulated connector test of finished unit with HB plastic
sheet - Ignitions verification . 84
Table 96 – Third RRT - Finished unit test of V2 Connectors with external NiCr wire -
Ignitions verification . 85
Table 97 – Third RRT - Finished unit test of V0 Connectors with external NiCr wire -
Ignitions verification . 86
Table 98 – Third RRT - V2 Connectors with external NiCr wire - Time to ignition . 87
Table 99 – Third RRT - V0 Connectors with external NiCr wire - Time to ignition . 88
Table 100 – Third RRT - Finished unit test of V2 Connectors with top plastic sheet HB -
Top specified layer time to ignitions . 90
Table 101 – Third RRT - Finished unit test of V0 Connectors with top plastic sheet HB -
Top specified layer time to ignitions . 91
Table 102 – Third RRT - Finished unit test of uninsulated connectors with top plastic
sheet HB - Top specified layer time to ignitions . 92
Table 103 – Third RRT - Finished unit test of uninsulated connectors with top plastic
sheet V0 - Top specified layer time to ignitions . 93
Table 104 – Third RRT - Bench test of V2 Connectors - Lower specified layer time to
ignitions . 94
Table 105 – Third RRT - Finished unit test of Uninsulated connectors with top plastic
sheet HB - Lower specified layer time to ignitions . 95
Table 106 – Third RRT - Finished unit test of V2 connectors with top plastic sheet HB -
Lower specified layer time to ignitions. 96
Table 107 – Third RRT - Finished unit test of V0 connectors with top plastic sheet HB -
Lower specified layer time to ignitions. 97
Table 108 – Third RRT - Bench test of V2 connectors - Flame duration . 98
Table 109 – Third RRT - Bench test of V0 connectors - Flame duration . 99
Table 110 – Third RRT - Finished unit test of V2 connectors - Flame duration . 100
Table 111 – Third RRT - Finished unit test of V0 connectors - Flame duration . 101
Table 112 – Third RRT - Plastic insulating connectors achieved ignitions outcome . 102
Table 113 – Third RRT - Low specified layer achieved ignitions outcome . 102
Table 114 – Third RRT - Top specified layer achieved ignitions outcome . 103
Table 115 – Third RRT - Plastic insulating connector tests outcome . 103
Table 116 – Third RRT - Finished unit tests outcome . 103
Table 117 – Third RRT - Uninsulated connector tests outcome . 104
Table 118 – Round robin test results - Plastic insulating connectors achieved ignitions
analysis by round robin test . 105
Table 119 – Round robin test results - Plastic insulating connectors achieved ignitions
analysis . 105
Table 120 – Round robin test results - Plastic insulating connectors time to ignitions
analysis by round robin test . 106
Table 121 – Round robin test results - Plastic insulating connectors time to ignitions
analysis by NiCr wire application method . 106
Table 122 – Round robin test results - Plastic insulating connectors flame durations
analysis by round robin test . 106
Table 123 – Round robin test results - Plastic insulating connectors flame durations
analysis by NiCr wire application method . 107
Table 124 – Round robin test results - Finished unit enclosures achieved ignitions
analysis by round robin test . 107
Table 125 – Round robin test results - Finished unit enclosures achieved ignitions
analysis by NiCr wire application method . 108

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Fire hazard testing -
Part 2-22: Glowing/hot-wire based test methods - Results of the round
robin tests for the development of IEC TS 60695-2-21:2023

FOREWORD
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