UL 1439 STANDARD FOR SAFETY Tests for Sharpness of Edges onEquipment

UL 1439 STANDARD FOR SAFETY Tests for Sharpness of Edges onEquipment 1 Scope 1.1These 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. 2Units of Measurement 2.1Values stated without parentheses are the requirement. Values in parentheses are explanatory orapproximate information. 3 Undated References 3.1 Any undated reference to a code or standard appearing in the requirements of this standard shall beinterpreted as referring to the latest edition of that code or standard. cONSTRUCTION 4General 4.1 An edge of an enclosure opening， frame, guard， knob， handle or the like of an appliance orequipment shall be smooth and rounded so as not to cause a cut-type injury when contacted duringnormal use or user maintenance. Exception: A sharp edge that must be exposed to enable the product to perform its intended function neednot 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 cylindrical steel, with an outside diameter of 1/2 in (12.7 mm) and alength of 3/4 in (19 mm), located at the end of the adjustable arm. The arm head is to be wrappedwith three layers of tape, the two outer layers act as sensing tapes; the inner layer acts as anindicating tape.Alternately, the tapes are to be applied to a removable sleeve or cap that is placedonto the 1/2 in (12.7 mm) steel arm head.The sleeve or cap shall not exceed 5/8 in (15.9 mm) in