{"data":{"id":"us/30-cfr-7.305","jurisdiction":"us","citation":"30 CFR 7.305","heading":"Critical characteristics.","body":"The following critical characteristics shall be inspected on each motor assembly to which an approval marking is affixed:\n(a) Finish, width, and planarity of surfaces that form any part of a flame-arresting path.\n(b) Clearances between mating parts that form flame-arresting paths.\n(c) Thickness of walls, flanges, and covers that are essential in maintaining the explosion-proof integrity of the enclosure.\n(d) Spacing of fastenings.\n(e) Length of thread engagement on fastenings and threaded parts that assure the explosion-proof integrity of the enclosure.\n(f) Use of lockwasher or equivalent with all fastenings.\n(g) Dimensions which affect compliance with the requirements for packing gland parts in § 7.304 of this part.","path":["Title 30—Mineral Resources","CHAPTER I—MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR","SUBCHAPTER B—TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS","PART 7—TESTING BY APPLICANT OR THIRD PARTY","Subpart J—Electric Motor Assemblies"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-30.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:25:24Z","sha256":"1154f2a11aa22d2b40607d2c07c630a2254bbd12c3df3ad3330cb61e79b38691","source_id":"us-cfr","stale":true,"prev":"us/30-cfr-7.304","next":"us/30-cfr-7.306"},"notice":"GroundRules: Original legal text. Not legal advice."}