These requirements cover industrial control equipment for installation and use in hazardous (classified) locations@ Class I@ Division 1@ Groups A@ B@ C@ and D@ and Class II@ Division 1@ Groups E@ F@ and G@ in accordance with the National Electrical Code@ NFPA 70. These requirements also cover explosion-proof electrical equipment for installation and use in Class I@ Zone 1@ Groups IIA@ IIB@ IIB plus Hydrogen@ and IIC hazardous (classified) locations. Examples of industrial control equipment are: a) Manual and magnetic starters and controllers. b) Thermal- and magnetic-overload relays. c) Pushbutton stations@ including selector switches and pilot lights. d) Control-circuit switches and relays. e) Float-@ flow-@ pressure-@ and vacuum-operated switches. f) Resistors and rheostats. g) Proximity switches. h) Time-delay relays and switches. i) Resistors and rheostats intended for industrial heating and lighting@ including those for motorgenerator fields. j) Control devices intended for industrial heating and lighting. k) Variable-voltage autotransformers. These requirements apply to industrial control equipment for use in hazardous locations under the following atmospheric conditions: a) A minimum ambient temperature of minus 25??(minus 13??@ b) An oxygen concentration not greater than 21 percent by volume@ and c) A nominal barometric pressure of one atmosphere. These requirements do not cover intrinsically-safe electrical circuits of industrial control equipment for use in hazardous locations.These requirements do not cover electrostatic devices@ circuits@ or systems. These requirements do not cover refrigeration-system controllers or the internal construction of electrical instruments such as meters. A product that contains features@ characteristics@ components@ materials@ or systems new or different from those covered by the requirements in this standard@ and that involves a risk of fire@ electric shock@ or injury to persons shall be evaluated using the appropriate additional component and end-product requirements as determined necessary to maintain the acceptable level of safety as originally anticipated by the intent of this standard. A product whose features@ characteristics@ components@ materials@ or systems conflict with specific requirements or provisions of this standard cannot be judged to comply with this standard. Where considered appropriate@ revision of requirements shall be proposed and adopted in conformance with the methods employed for development@ revision@ and implementation of this standard.