UL 1439:1998 pdf download Tests for Sharpness of Edges on Equipment
1 Scope
1.1 These requirements cover a test procedure to be used to determine the potential personal injuryrelated 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 orapproximate information.
3 References
3.1 Any undated reference to a code or standard appearing in the requirements of this standard shal beinterpreted as referring to the latest edition of that code or standard.
4General
4.1 An edge of an enclosure opening, frame, guard, knob, handle or the like of an appliance or equipmentshall be smooth and rounded so as not to cause a cut-type injury when contacted during normal use oluser maintenance.
Exception: A sharp edge that must be exposed to enable the product to perform its intended functiorneed not comply 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 armattached. A constant-tension spring secured to the handle is used to apply a steady force to thearm. The arm head is a piece of round steel, with an outside diameter of 1/2 inch (12.7 mm)located at the end of the adjustable arm. The arm head is to be wrapped with three layers oftape, the two outer layers act as sensing tapes; the inner layer acts as an indicating tape, or thetapes are to be applied to a 5/8 inch (15.9 mm) removable sleeve that is placed onto the 1/2inch (12.7 mm) steel head. See Figure 5.1 or 5.2
b) Indicating Tape (lnner Layer) – 3/4 inch (19.1 mm) wide, adhesive backed, single-adhesivecoated, vinyl foam tape, black in color, having the tape properties given in Table 5.1.
c) Sensing Tape No. 2 (Middle Layer) – 3/4 inch (19.1 mm) wide, double-adhesive coated, vinylfoam tape, white in color, having the tape properties given in Table 5.1.
d) Sensing Tape No. 1 (Outer Layer) – 3/4 inch (19.1 mm) wide, single-adhesive coated skivedtetrafluorethylene tape – natural color, having the tape properties given in Table 5.1. The skivedtetrafluorethylene backing (film) is shaved in a thin layer from a cylindrical block of material.
6 Calibration of Tester
6.1 The sharp edge tester shall be calibrated so that a 1 -1 /2 lbf (6.7 N) is present at the center of the head when the arm is between stops. The length of the arm is to be adjustable for calibration purposes. See Figure 6.1 for a typical calibration procedure.