CNS (Central Nervous System) Oxygen Toxicity in Closed-Circuit SCUBA Divers.

Rubicon Research Repository/Manakin Repository

CNS (Central Nervous System) Oxygen Toxicity in Closed-Circuit SCUBA Divers.

Show full item record


Title: CNS (Central Nervous System) Oxygen Toxicity in Closed-Circuit SCUBA Divers.
Author: Butler Jr, FK; Thalmann, ED
Abstract: Sixty-Eight man-dives were conducted at the navy experimental Diving Unit to evaluate the feasibility of extending oxygen diving tables currently used by U.S. Navy closed-curcuit oxygen SCUBA divers. Additionally, testing was done to determine the cumulative effect of previous shallower oxygen exposures on subsequent excursions to increased depth. Twenty minute exposures at 40 FSW were found unsafe, with 2 convulsions resulting from a total of 17 dives. Fifteen minute exposures resulted in no convulsions or "Definite" symptoms occurring on a total of 24 dives. Excursions to 40 FSW for 15 minutes after a previous 1 hour exposure at 25 FSW, resulted in 1 "Definite" toxicity episode in 13 dives. Excursions to 40 FSW, following a 2 hour exposure at 25 FSW, produced 2 "Definite" toxicity episodes in 13 dives. One convulsion was seen after a 72 minute exposure at 25 FSW. The following conclusions are made from the study: (a) Oxygen toxicity convulsions may be seen during what are usually considered safe exposures, as evidenced by the convulsion which occurred after only a 72 minute exposure at 25 FSW; (b) The current limit of 10 minutes at 40 FSW in the U.S. Navy Diving manual will certainly not be extended beyond 15 minutes. Further dives at 40 FSW for 15 minutes are necessary to determine whether or not this profile is safe for operational use; (c) Brief excursions to 40 FSW were possible after a prolonged exposure to oxygen at 25 FSW. Pre-exposures of 60 minutes at 25 FSW do not seem to influence the safe 40 FSW exposure time but a 2-hour pre-exposure did seem to decrease the safe 40 FSW exposure time somewhat.
Description: Citation Status: Active; Citation Classification: Unclassified; Title Classification: Unclassified; Report Classification: Unclassified; Identifier Classification: Unclassified; Abstract Classification: ; Distribution Limitation(s): 01 - APPROVED FOR PUBLIC RELEASE; Information provided by the Department of Defense and the Defense Technical Information Center (http://www.dtic.mil/) is considered public information and may be distributed or copied unless otherwise specified. Use of appropriate byline/photo/image credits is requested.
URI: http://archive.rubicon-foundation.org/3378
Date: 1984

Files in this item

Files Size Format View
NEDU_1984_11.pdf 2.712Mb PDF View/Open

This item appears in the following Collection(s)

Show full item record

Browse

My Account