UL 1439-2011 pdf download

UL 1439-2011 pdf download.Tests for Sharpness of Edges on Equipment.
1.1 These requirements cover a test procedure to be used to determine the potential personal injury
related to the sharpness of edges that are part of or associated with appliances and equipment.
1.2 Deleted June 1, 2004.
2 Units of Measurement
2.1 Values stated without parentheses are the requirement. Values in parentheses are explanatory or
approximate information.
3 References
3.1 Any undated reference to a code or standard appeanng in the requirements of this standard shall be interpreted as refernng to the latest edition of that code or standard.
4 General
4.1 An edge of an enclosure opening, frame, guard, knob, handle or the like of an appliance or equipment shall be smooth and rounded so as not to cause a cut-type injury when contacted during normal use or user maintenance.
Exception: A sharp edge that must be exposed to enable the product to perform its intended function need not coniply with the requirement in 4.1.
TESTS
5 Apparatus
5.1 The test apparatus Is to consist of the following:
a) Sharp-Edge Tester — The instrument consists essentially of a handle with a pivoted arm attached. A constant-tension spring secured to the handle is used to apply a steady force to the arm. The ami head is a piece of cylindrical steel, with an outside diameter of 1/2 inch (12.7 mm) and a length of 3/4 inch (19 mm). located at the end of the adustable arm. The arm head is to be wrapped with three layers of tape, the iwo outer layers act as sensing tapes; the inner layer acts as an indicating tape. Alternately, the tapes are to be applied to a removable sleeve or cap that is placed onto the 1/2-inch (12.7-mm) steel arm head. The sleeve or cap shall not exceed 5/8 inch (15.9 mm) in diameter. See Figure 5.1 or 5.2.
b) Indicating Tape (Inner Layer) — 3/4-inch (19.1-mm) wide, adhesive backed, single-adhesive coated, vinyl foam tape, black in color, having the tape properties given in Table 5.1.
C) Sensing Tape No. 2 (Middle Layer) — 314-inch (19.1-mm) wide, double-adhesive coated, vinyl foam tape, white in color, having the tape properties given in Table 5.1.
d) Sensing Tape No. 1 (Outer Layer) — 34 inch-(19.1-mm) wide, single-adhesive coated skived tetrafluorethylene tape — natural color, having the tape properties given in Table 5.1. The skived tetrafluorethylene backing (film) Is shaved In a thin layer from a cylindrical block of material,
7.2 Each tape is to be applied over approximately 180 degrees of the circumference of the test head to prevent stretching of the tape.
7.3 The tapes are not to be stretched when positioned on the head. See Figure 7.1
7,4 The center of the tape-covered head of the sharp-edge tester shall be positioned on the edge to be tested in the manner illustrated in Figure 7.2. The arm of the tester shall be between stops so that th€ tape-covered head exerts a 1-1/2 IbI (6.7 N) on the edge. The tester shall be immediately moved along the edge a cstance of 2 inches (50.8 mm) and then back to its starting position without removal of the tester from the edge. It shall then be withdrawn from the edge. The total distance of engagement between the edge and the tape-covered head is not to exceed 4 inches (101 mm). The time of travel is not to take longer than 5 seconds nor less than 2 seconds.
Exception: An edge less than 2 inches (50.8 mm) long shall be tested for a distance of twice its length. (Example: For an edge 1-1,2 ,nches or 41.2mm long, the tester is to be moved along its length and back to the starting position so that the total distance of engagement between the edge and tester is 3 inches or 76.2 mm).