1.1This specification covers annealed, drawn, or rolled shapes for electrical heating and resistance purposes of alloys consisting mainly of iron, chromium, and aluminum as detailed in Table 1.

TABLE 1 Chemical Requirements

Class	Resistivity Range		Composition Range, %
	Ω·cmil/ft	μΩ·cm	Al	Cr
I	825 to 920	135 to 150	5.00 to 6.00	20 to 24
IIA	795 to 880	130 to 144	4.75 to 5.75	20 to 24
IIB	770 to 855	130 to 144	4.00 to 5.25	20 to 24
III	715 to 785	119 to 130	3.75 to 4.75	13 to 16
IV	665 to 735	111 to 122	2.75 to 3.75	12 to 15

1.2The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.3This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Material Safety Data Sheet (MSDS) for this product/material as provided by the manufacturer, to establish appropriate safety and health practices, and determine the applicability of regulatory limitations prior to use.