23.2—Definitions.
(a)
Adequate means appropriate and sufficient, as determined by mutual agreement of the manufacturer, operators, and MSHA.
(b)
Approval means official notification by letter, from MSHA to a responsible organization, stating that the device under consideration has been judged to meet the requirements of this part.
(c)
Normal operation means the performance by each part of the device of those functions for which the part was designed.
(d)
Permissible as used in this part means completely assembled and conforming in every respect with the design formally approved by MSHA under this part. (Approvals under this part are given only to equipment for use in gassy and dusty mines.)
(f) Signaling device.
As used in this part, a signaling device is one that gives visual or audible signals.
(g)
MESA means the United States Department of the Interior, Mining Enforcement and Safety Administration. Predecessor orgainzation to MSHA, prior to March 9, 1978.