UL-44:2010 pdf free download – Underwriters Laboratories Inc. Standard for Safety Thermoset-Insulated Wires and Cables.
5.14.5 Vertical-tray (optional)
Finished wires or cables shall not exhibit damage that reaches the upper end of any of two sets of specimens when subjected to the test, Vertical tray flame tests (Method 1-vertical tray), in UL 2556, CSA C22.2 No. 2556, or NMX-J-498-ANCE.
5.14.6 FT4 vertical-tray (optional)
Finished wires or cables shall not exhibit charred material beyond a length exceeding 1.5 m (5 ft) from the lower edge of the burner face when subjected to the test, Vertical tray flame tests (Method 2-FT4), in UL 2556, CSA C22.2 No. 2556, or NMX-J-556-ANCE. Conductors complying with this requirement need not be subjected to the test described in Clause 5.14.5.
5.14.7 ST1 limited smoke (optional)
5.14.7.1 General
When subjected to the test, ST1 limited smoke, in UL 2556, CSA C22.2 No. 2556, or NMX-J-556-ANCE, each finished insulated single conductor shall comply with the test criteria in Clauses 5.14.5 or 5.14.6. Limits are specified for each fire test to make the following tests equally acceptable for the purpose of quantifying the smoke. The cable manufacturer shall specify, for testing each “STi” (limited smoke) cable construction, the vertical flame exposure referenced in either Clause 5.14.5 or 5.14.6.
For a range of sizes to be marked “STi “, typically the smallest conductor in the range, the smallest conductor employing the same insulation thickness as the largest conductor in the range, and an intermediate conductor shall be selected for testing. Individual conductor sizes may be tested.
5.14.7.2 Vertical-tray flame exposure
Finished wires or cables shall exhibit the following properties when subjected to the test, Vertical tray flame tests (Method 1 — vertical tray), in UL 2556, CSA C22.2 No. 2556, or NMX-J-556-ANCE:
a) The cable damage height for each set of specimens shall be less than 2.44 m (8 ft) when measured from the bottom of the cable tray.
b) The total smoke released in 20 mm for each set of specimens shall not exceed 95 m2.
c) The peak smoke release rate for each set of specimens shall not exceed 0.25 m2/s.
d) The values of cable damage height, total smoke released, and peak smoke release rate obtained from one set of specimens shall not differ by more than 15 percent from the values
obtained from the second set of specimens. If any of the values differ by more than 15 percent between the two sets of specimens, a third set of specimens shall be tested. The values
obtained from the third set of specimens shall be within the limits in items a), b), and c).
5.14.7.3 FT4 vertical-tray flame exposure
Finished wires or cables shall exhibit the following properties when sets of specimen lengths are subjected to the test, Vertical tray flame tests (Method 2 — FT4), in UL 2556, CSA C22.2 No. 2556, or NMX-J-556-ANCE:
a) The cable damage height for each set of specimens shall be less than 1 .50 m when measured from the lower edge of the burner face.
b) The total smoke released in 20 minutes for each set of specimens shall not exceed 150 m2.
c) The peak smoke release rate for each set of specimens shall not exceed 0.40 m2/s.