{"data":{"id":"us/46-cfr-appendix-a-to-part-197","jurisdiction":"us","citation":"46 CFR Appendix A to Part 197","heading":"Appendix A to Part 197—Air No-Decompression Limits","body":"The following table gives the depth versus bottom time limits for single, no-decompression, air dives made within any 12-hour period. The limit is the maximum bottom time in minutes that a diver can spend at that depth without requiring decompression beyond that provided by a normal ascent rate of 60 fsw per minute. (Although bottom time is concluded when ascent begins, a slower ascent rate would increase the bottom time thereby requiring decompression.) An amount of nitrogen remains in the tissues of a diver after any air dive, regardless of whether the dive was a decompression or no-decompression dive. Whenever another dive is made within a 12-hour period, the nitrogen remaining in the blood and body tissues of the diver must be considered when calculating his decompression.\nAir No-Decompression Limits\nDepth (feet): No-decompression limits (minutes)\n35 310\n40 200\n50 100\n60 60\n70 50\n80 40\n90 30\n100 25\n110 20\n120 15\n130 10\n(Source: U.S. Navy Diving Manual, 1 September 1973.)","path":["Title 46—Shipping","CHAPTER I—COAST GUARD, DEPARTMENT OF HOMELAND SECURITY","SUBCHAPTER V—MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS","PART 197—GENERAL PROVISIONS"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-46.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:22Z","sha256":"a153b7a9e1b3c0f71a30eb37df7c6f17f247956dd1f943704fb1fa145f03be56","source_id":"us-cfr","stale":true,"prev":"us/46-cfr-appendix-f-to-subpart-c-of-part-197","next":"us/46-cfr-199.01"},"notice":"GroundRules: Original legal text. Not legal advice."}