UL 499:2008 pdf download.Electric Heating Appliances.
6.28 The sheath employed to enclose the heating element of an immersion-type heater for use with fueloil shall be of steel, stainless steel, or other metal resistant to corrosion in fuel oil; brass, bronze, or copperis not considered acceptable for this application. The sheath employed to enclose the heating element ofan immersion-type water heater shall be of a metal resistant to corrosion in water.
6.29 Openings provided in a soldering tool, such as for ventilating purposes,shall be of such size andorientation with respect to the soldering tip that entry of falling or dripping molten solder, or unintentionalinsertion of solder wire is not likely to contact，bridge,or otherwise reduce the spacings betweenuninsulated live parts of opposite polarity, or uninsulated live parts and accessible dead metal parts.Consideration shall be given to the orientation of the soldering tool during use.
6.30 A cord-connected product that is provided with keyhole slots,notches, hanger holes, or the like, formounting the product on a wall shall be constructed in such a manner that the mounting means shall notbe accessible without removing the product from the supporting means.
6.31 When determining compliance with 6.30, any part of the enclosure or barriers that can be removedwithout the use of tools to gain access to the mounting means are to be removed.
6.32 A keyhole slot，notch,or hanger hole shall be located so that the supporting screws or the likecannot damage any electrical insulation or contact uninsulated current-carrying parts of the product.
7 Assembly
7.1 A soldering iron, or other cord-connected heating appliance that is likely to be laid on combustiblematerial shall be provided with a stand of noncombustible material upon which it may be placed when notin use,unless the temperature attained by the product is not high enough to cause the ignition of thecombustible material.
7.2 The stand may be a separate device or attached to the product, except that an integral type of standis required for a charcoal ignitor.
