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Scope: This standard specifies the apparatus for testing the resistance to vertical flame spread of a single insulated wire or cable, or fiber optic cable under specified conditions. The apparatus is given in EN 60332-1-1. NOTE 1: The test of EN 60332-1-2 can be performed together with that of EN 60332-1-3 if required. Recommended performance requirements are given in Annex A. EN 60332-1-2 specifies the use of a 1 kW premixed flame and is for general use except that the specified procedure may not be suitable for testing small single insulated conductors with a total cross-section of less than 0.5 mm?, because the conductor melts before the test is completed, or for the test of small fiber optic cables, because the cable breaks before the test is completed. n these cases, the procedure given in EN 60332-2-2 is recommended. NOTE 2: Since the use of insulated wire or cable which retards the spread of flame and meets the recommended requirements of this standard is not sufficient by itself to prevent the spread of fire under all installation conditions, it is recommended wherever the risk of spread is high, for example with long vertical cable bundles, special precautions must also be taken during installation. It cannot be assumed that because a sample of cable meets the performance requirements recommended in this standard, a group of cables will behave similarly. (See EN 60332-3 series.) It has group safety publication status according to IEC Guide 104.
Test specimen:
The test specimen shall be a piece of single insulated wire or cable measuring (600 ± 25) mm in length.
The diameter of the test specimen shall be measured by the method given in IEC 60811-203. The measurement must be taken at each of the three locations, spaced at least 100 mm apart.
The average of the three values obtained must be rounded to obtain the outer diameter.
The resulting outer diameter should be used to select the time to apply the flame.
Duration of the test
The flame shall be applied for a period of time corresponding to the diameter shown in Table 1.
Table 1 – Flame application time
Outer diameter of the test specimen а mm |
Flame application time s |
D≤25 25< D ≤50 50<D≤75 D>75 |
60 ± 2 120 ± 2 240 ± 2 480 ± 2 |
a For non-circular cross-section cables whose major to minor axis ratio is less than 3, the nominal minor axis should be used as the outside diameter (D). For non-circular cross-section cables where the major to minor axis ratio is between 3 and 16, the sum of the major and minor axes divided by 3.14 (p) should be taken as the outer diameter (D). For cables where the ratio of major to minor exceeds 16, the test criterion shall be given in the product standard or, if none, by agreement between the manufacturer and the purchaser. |
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Assessment of test results
After the combustion has stop the test specimen is cleaned by wiping.
Any soot coating is ignored if the original surface is not damaged after cleaning. Softening or deformation of non-metallic materials is also not taken into account. The distance from the lower end of the upper support to the beginning of the charred area at the top of the specimen and the distance from the lower end of the upper support to the beginning of the charred area at the lower part of the specimen shall be measured to the nearest millimeter.
The beginning of the charred area should be determined as follows:
Press the surface of the cable with a sharp object, such as a knife blade. Where the surface changes from elastic to brittle (crumbly), this indicates the beginning of a charred area.
