The Nervous System

The nervous system coordinates all body functions and activities. The nervous system comprises the brain, spinal cord, and a complex network of nerves that course through the body. The brain and spinal cord are collectively referred to as the central nervous system (CNS). Nerves originating in the brain and spinal cord and traveling to peripheral parts of the body form the peripheral nervous system (PNS). The peripheral nervous system consists of the cranial nerves, the spinal nerves, and the...

Omitted Decompression215

21-3.1 Planned and Unplanned Omitted 21-3.2 Treating Omitted Decompression with 21-3.3 Treating Omitted Decompression in Specific Operational Environments 21-7 21-3.4 Ascent from 20 Feet or Shallower (Shallow Surfacing) with Decompression Stops 21-3.5 Ascent from 20 Feet or Shallower with No Decompression Stops Required 21-7 21-3.6 Ascent from Deeper than 20 Feet (Uncontrolled Ascent) 21-7 21-3.6.1 Asymptomatic Uncontrolled 21-3.6.2 Development of 21-3.6.3 In-Water 21-3.6.4 Symptomatic...

Equipment Cleanliness

Cleanliness and the procedures used to obtain cleanliness are a concern with NITROX systems. MILSTD 1330 is applicable to anything with an oxygen level higher than 25 percent by volume. Therefore, MILSTD 1330 must be followed when dealing with NITROX systems. Personnel involved in the maintenance and repair of NITROX equipment shall complete an oxygen clean worker course, as described in MILSTD 1330. Even with oxygen levels of 25 to 40 percent, there is still a greater risk of fire than with...

Nitrox Repetitive Diving

Repetitive diving is possible when using NITROX or combinations of air and NITROX. Once the EAD is determined for a specific dive, the Standard Navy Air Tables are used throughout the dive using the EAD from Table 10-1. The Residual Nitrogen Timetable for Repetitive Air Dives will be used when applying the EAD for NITROX dives. Determine the Repetitive Group Designator for the dive just completed using either Table 9-7, Unlimited No-Decompression Limits and Repetitive Group Designation Table...

Medical Aspects Of Closedcircuit Oxygen Diving181

18-2.1 Oxygen 18-2.1.2 Pulmonary Oxygen 18-2.1.3 Symptoms of CNS Oxygen 18-2.1.4 Causes of CNS Oxygen 18-2.1.5 Treatment of Nonconvulsive 18-2.1.6 Treatment of Underwater 18-2.2 Oxygen Deficiency 18-2.2.1 Causes of Hypoxia with the MK 25 UBA 18-5 18-2.2.2 Underwater 18-2.2.3 MK 25 UBA Purge 18-2.2.4 Symptoms of 18-2.2.5 Treatment of 18-2.3 Carbon Dioxide Toxicity 18-2.3.1 Symptoms of 18-2.3.2 Treating 18-2.3.3 Avoiding 18-2.4 Chemical 18-2.4.1 Causes of Chemical 18-2.4.2 Symptoms of Chemical...

Info

Fy Floodable volume of flask in cubic feet Pi Initial Pressure in psia PR Reserve Pressure in psia VO2 Oxygen consumption in medical scfm (32 F) T2 Coldest water temperature expected in R All pressure and temperature units must be absolute. 17-4.1.1.5 Example. The endurance of a MK 16 MOD 0 UBA charged to 2,500 psig for a dive in 50 F water when the ambient air temperature is 65 F would be computed as follows A rx,1R , ni (2, 514.7 x 510 525) - 514.7 492 MK 16 gas endurance 01 X -0.049 x 14.7-X...

Measurement

Physics relies heavily upon standards of comparison of one state of matter or energy to another. To apply the principles of physics, divers must be able to employ a variety of units of measurement. 2-4.1 Measurement Systems. Two systems of measurement are widely used throughout the world. Although the English System is commonly used in the United States, the most common system of measurement in the world is the International System of Units. The International System of Units, or SI system, is a...

Army Engineer Diving

FM 5-490, Engineer Diving Operations, provides a doctrinal basis for planning and using engineer divers in the theater of operations (TO). It describes the responsibilities, procedures, capabilities, constraints, and planning considerations for conducting underwater operations throughout the TO. Table of organization and equipment (TOE) numbers 05-530LA00 and 05-530LC00 establish the organizational structure, manning, and equipment authorizations for the engineer diving teams. The US Army...

Predive Procedures

The predive activities for a surface-supplied diving operation involve many people and include inspecting and assembling the equipment, activating the air supply systems, and dressing the divers. 8-8.1 Predive Checklist. A comprehensive predive checklist is developed to suit the requirements of the diving unit and of the particular operation. This is in addition to the general Diver Safety and Planning Checklist (Figure 6-19a) and suggested Predive Checklist (Figure 6-21a). 8-8.2 Diving Station...

Designation Table For Unlimitednodecompression Air Dives

The Unlimited No-Decompression Table (Table 9-6) serves three purposes. First, the table identifies that on a dive with the depth 20 fsw and shallower, unlimited bottom time may be achieved. Second, it summarizes all the depth and bottom time combinations for which no decompression is required. Third, it provides the repetitive group designation for each unlimited no-decompression dive. Even though decompression is not required, there is still an amount of nitrogen remaining in the diver's...

Selection Of Storage Depth

The selection of the storage depth for the deck decompression chamber (DDC) is based on the approximate planned diver working depth. This can be achieved by comparing the storage depth and planned diver working depth with the descent and ascent limits of the Unlimited Duration Excursion Tables (Table 15-7 and Table 15-8). When the diver's working depth range is small, the DDC should be compressed to approximately the middle of the range. This minimizes the amount of gas used in pressurizing or...

Diver Communications

The surface-supplied diver has two means of communicating with the surface, depending on the type of equipment used. If the diver is using the MK 21 MOD 1, or the MK 20 MOD 0, both voice communications and line-pull signals are available. Voice communications are used as the primary means of communication. Line-pull signals are used only as a backup. Diver-to-diver communications are available through topside intercom, diver-to-diver hand signals or slate boards. 8-7.1 Diver Intercommunication...

Arterial Gas Embolism 201

20-2.1 Arterial Embolism 20-2.2 Unconsciousness Caused by Arterial Gas Embolism 20-2 20-2.3 Neurological Symptoms of Arterial Gas Embolism 20-2 20-2.4 Additional Symptoms of Arterial Gas 20-2.5 Neurological Examination 20-2.6 Administering Advanced Cardiac Life Support (ACLS) in the 20-2.7 Prevention of Arterial Gas 20-3 DECOMPRESSION 20-3.1 Initial Episode of Decompression 20-3.2 Differentiating Type I and Type II 20-3.3 Type I Decompression 20-3.3.1 Musculoskeletal Pain-Only Symptoms 20-5...

Operational Planning178

17-4.1 Operating 17-4.1.1 Oxygen Flask 17-4.1.2 Diluent Flask 17-4.1.3 Canister 17-4.1.4 Thermal 17-4.2 Equipment 17-4.2.1 Distance 17-4.2.2 Standby 17-4.2.3 17-4.2.4 Marking of 17-4.2.5 Diver Marker 17-4.2.6 Depth Gauge Wrist 17-4.3 Recompression Chamber 17-4.4 Diving Procedures for MK 17-4.4.1 Employing a Single, Untended EOD Diver 17-15 17-4.4.2 Simulated Training 17-4.4.3 EOD Standard Safety 17-4.4.4 Diving 17-4.5 Ship 17-4.6 Operational Area

Gas Analysis

The precise determination of the type and concentration of the constituents of breathing gas is of vital importance in many diving operations. Adverse physiological reactions can occur when exposure time and concentrations of various components in the breathing atmosphere vary from prescribed limits. Analysis of oxygen content of helium-oxygen mixtures shall be accurate to within + 0.5 percent. The quality of the breathing gas is important in both air and mixed-gas diving. In air diving, the...

Nitrox Diving Procedures

10-4.1 NITROX Diving Using Equivalent Air Depths. NITROX diving is based upon the current U.S. Navy Air Decompression Tables. The actual schedule used is adjusted for the oxygen percentage in the breathing gas. To use the EAD Decompression Selection Table (Table 10-1), find the actual oxygen percentage of the breathing gas in the heading and the diver's actual depth in the left column to determine the appropriate schedule to be used from the U.S. Navy Air Decompression Tables. The EAD...

Physiological Hazards From Munitions

Divers frequently work with explosive material or are involved in combat swimming and therefore may be subject to the hazards of underwater explosions. An explosion is the violent expansion of a substance caused by the gases released during rapid combustion. One effect of an explosion is a shock wave that travels outward from the center, somewhat like the spread of ripples produced by dropping a stone into a pool of water. This shock wave moving through the surrounding medium (whether air or...

Deep Sea Salvage Rescue Diving Platforms

Auxiliary Rescue Salvage Ship (ARS) (Safeguard Class). The mission of the ARS ship is to assist disabled ships, debeach stranded vessels, fight fires alongside other ships, lift heavy objects, recover submerged objects, tow other vessels, and perform manned diving operations. The ARS class ships carry a complement of divers to perform underwater ship husbandry tasks and salvage operations as well as underwater search and recovery. This class of vessel is equipped for all air diving techniques....

Mixing Procedures

Two or more pure gases, or gas mixtures, may be combined by a variety of techniques to form a final mixture of predetermined composition. This section discusses the techniques for mixing gases. Aboard ships, where space is limited and motion can affect the accuracy of precision scales, gases are normally mixed by partial pressure or by continuous-flow mixing systems. The methods of mixing by volume or weight are most suitable for use in shore-based facilities because the procedure requires...

Surface Air Supply Systems

The diver's air supply may originate from an air compressor, a bank of high-pressure air flasks, or a combination of both. 8-6.1 Requirements for Air Supply. Regardless of the source, the air must meet certain established standards of purity, must be supplied in an adequate volume for breathing, and must have a rate of flow that properly ventilates the helmet or mask. The air must also be provided at sufficient pressure to overcome the bottom water pressure and the pressure losses due to flow...

Acfm at bottom conditions

Based upon an actual volume (displacement) flow requirement of 1.4 acfm for a deep-sea diver, the compressor capacity is sufficient to support the working and standby divers at 130 fsw. Sample Problem 3. Find the actual cubic feet of air contained in a 700-cubic inch internal volume cylinder pressurized to 3,000 psi. 1. Simplify the equation by eliminating the variables that will not change. The temperature of the tank will not change so T and T2 can be eliminated from the formula in this...

Medical Aspects Of Closedcircuit Oxygen Diving

Closed-circuit oxygen divers are subject to many of the same medical problems as other divers. Volume 5 provides in-depth coverage of all medical considerations. Only the diving disorders that merit special attention for closed-circuit oxygen divers are addressed in this chapter. Figure 18-1. Diver in Draeger LARV UBA. Figure 18-1. Diver in Draeger LARV UBA. 18-2.1 Oxygen Toxicity. Breathing oxygen at high partial pressures may have toxic effects in the body. Relatively brief exposure to...

NOTE When using externally powered tools with scuba the diver must have voice communications with the Diving Supervisor

Any tools to be used should be organized in advance. The diver should carry as few items as possible. If many tools are required, a canvas tool bag should be used to lower them to the diver as needed. Further guidelines for working underwater are provided in the U.S. Navy Underwater Ship Husbandry Manual (NAVSEA SO6OO-AA-PRO-010). Authorized power tools are listed in the NAVSEA 00C ANU list. 7-7.10 Adapting to Underwater Conditions. Through careful and thorough planning, the divers can be...

Light Energy In Diving

Refraction, turbidity of the water, salinity, and pollution all contribute to the distance, size, shape, and color perception of underwater objects. Divers must understand the factors affecting underwater visual perception, and must realize that distance perception is very likely to be inaccurate. 2-6.1 Refraction. Light passing from an object bends as it passes through the diver's faceplate and the air in his mask (Figure 2-5). This phenomenon is called refraction, and occurs because light...

Safety Precautions

The WARNINGS, CAUTIONS, and NOTES contained in this manual are defined as follows WARNING Identifies an operating or maintenance procedure, practice, condition, or statement, which, if not strictly observed, could result in injury to or death of personnel. CAUTION Identifies an operating or maintenance procedure, practice, condition, or statement, which, if not strictly observed, could result in damage to or destruction of equipment or loss of mission effectiveness, or long-term health hazard...

Diving Supervisor

An exception to this table occurs when the repetitive dive is made to the same or greater depth than that of the previous dive. This is referred to as the RNT Exception Rule. In such cases, the residual nitrogen time may be longer than the bottom time of the previous dive. A diver's body cannot contain more residual nitrogen than it was originally exposed to. To obtain the equivalent single dive time, simply add the bottom time of the previous dive to that of the...

Volume 2 List of Illustrations

6-1 Underwater Ship Husbandry 6-2 Salvage 6-3 Explosive Ordnance Disposal 6-4 Underwater Construction 6-5 Planning Data 6-6 Environmental Assessment 6-7 Sea State 6-8 Equivalent Windchill Temperature 6-10 Bottom Conditions and Effects 6-11 Water Temperature Protection 6-12 International Code Signal 6-13 Air Diving 6-14 Normal and Maximum Limits for Air 6-15 MK 21 Dive Requiring Two 6-16 Minimum Personnel Levels for Air Diving 6-17 Master Diver Supervising Recompression 6-18 Standby 6-19a Diving...

Diving Personnel

6-9.7.1 Diving Personnel Responsibilities. While working, the diver shall keep topside personnel informed of conditions on the bottom, progress of the task, and of any developing problems that may indicate the need for changes to the plan or a call for assistance from other divers. To ensure safe conduct of the dive, the diver shall always obey a signal from the surface and repeat all commands when using voice communications. The diver is responsible for the diving gear worn and shall ensure...

Objectives Of The Record Keeping And Reporting System

There are five objectives in the diving record keeping and reporting system. 1. Establish a comprehensive operational record for each diving command. The Command Smooth Diving Log is a standardized operational record prepared in accordance with established military practice. This record establishes the diving history for each diving command and constitutes the basic operational record requirement under normal, uneventful circumstances. 2. Gather data for safety and trend analysis. Information...

Warning

The gag valve must remain open at all times. Close only if relief valve fails. 22-5.4 Ventilation. The basic rules for ventilation are presented below. These rules permit rapid computation of the cubic feet of air per minute (acfm) required under different conditions as measured at chamber pressure (the rules are designed to ensure that the effective concentration of carbon dioxide will not exceed 1.5 percent (11.4 mmHg) and that when oxygen is being used, the percentage of oxygen in the...

Nitrox Diving Equipment

NITROX diving can be performed using a variety of equipment that can be broken down into two general categories surface-supplied or closed- and open-circuit scuba. Closed-circuit scuba apparatus is discussed in Chapter 17. 10-8.1 Open-Circuit Scuba Systems. Open-circuit scuba systems for NITROX diving are identical to air scuba systems with one exception the scuba bottles are filled with NITROX (nitrogen-oxygen) rather than air. There are specific regulators authorized for NITROX diving, which...

Compression Phase

The initial phase of the dive is the compression of the dive team to the selected storage depth. This phase includes establishing the chamber oxygen partial pressure at a value between 0.44 and 0.48 ata, instrument and systems checkouts, and the actual compression of the divers to storage depth. 15-20.1 Establishing Chamber Oxygen Partial Pressure. Prior to compression to storage depth, the chamber oxygen partial pressure shall be raised from 0.21 ata to 0.440.48 ata. There are two methods of...

Command Smooth Diving

The Command Smooth Diving Log is a chronological record of all dives conducted at that facility or command. It contains information on dives by personnel attached to the reporting command and dives by personnel temporarily attached to the command, such as personnel on TAD TDY. Dives conducted while temporarily assigned to another diving command shall be recorded in the host command's Smooth Diving Log. Additionally, record the dive in the Dive Reporting System (DRS) of the host command. The...

Surfacesupplied Air Diving

The origins of diving are firmly rooted in man's need and desire to engage in maritime commerce, to conduct salvage and military operations, and to expand the frontiers of knowledge through exploration, research, and development. Diving, as a profession, can be traced back more than 5,000 years. Early divers confined their efforts to waters less than 100 feet deep, performing salvage work and harvesting food, sponges, coral, and mother-of-pearl. A Greek historian, Herodotus, recorded the story...

Standby Diver Qualifications

Standby diver is a fully qualified diver, assigned for back-up or to provide emergency assistance, and is ready to enter the water immediately. For surface-supplied operations, the standby diver shall be dressed to the following points, MK 20 or MK 21 MOD 1, with strain relief connected to the harness. Under certain conditions, the Diving Supervisor may require that the helmet be worn. A standby scuba diver shall don all equipment and be checked by the Diving Supervisor. The standby diver may...

Identify Environmental And Operational Hazards

Underwater environmental conditions have a major influence on the selection of divers, diving technique, and the equipment to be used. In addition to environmental hazards, a diver may be exposed to operational hazards that are not unique to the diving environment. This section outlines the environmental and operational hazards that may impact an operation. 6-6.1 Underwater Visibility. Underwater visibility varies with depth and turbidity. Hori zontal visibility is usually quite good in...

C4 Poisonous Marine Animals

Ciguatera poisoning is fish poisoning caused by eating the flesh of a fish that has eaten a toxin-producing microorganism, the dinoflagel-late, Gambierdiscus toxicus. The poisoning is common in reef fish between latitudes 35 N and 35 S around tropical islands or tropical and semitropical shorelines in Southern Florida, the Caribbean, the West Indies, and the Pacific and Indian Oceans. Fish and marine animals affected include barracuda, red snapper, grouper, sea...

Divers Breathing Gas Purity Standards

Diver's air compressed from ANU or certified diving system sources shall meet the U.S. Military Diver's Breathing Air Standards contained in Table 4-1. Table 4-1. U.S. Military Diver's Compressed Air Breathing Purity Requirements for ANU Approved or Certified Sources. Table 4-1. U.S. Military Diver's Compressed Air Breathing Purity Requirements for ANU Approved or Certified Sources. Total hydrocarbons (as CH4 by volume) Diver's breathing air may be procured from...

A6 Guidance For Diver Exposure To Ultrasonic Sonar 250 KHz And Greater

The frequencies used in ultrasonic sonars are above the human hearing threshold. The primary effect of ultrasonic sonar is heating. Because the power of ultrasonic sonar rapidly falls off with distance, a safe operating distance is 10 yards or greater. Dive operations may be conducted around this type of sonar provided that the diver does not stay within the sonar's focus beam. The diver may finger touch the transducer's head momentarily to verify its operation as long as the sonar is...

Oxygen Toxicity

Although the use of NITROX can increase the diver's bottom time and reduce the risk of nitrogen narcosis, using a NITROX mixture raises the concern for oxygen toxicity. For example, using air as the breathing medium, an oxygen partial pressure (ppO2) of 1.6 ata is reached at a depth of 218 fsw. In contrast, when using the NITROX mixture containing 60 percent nitrogen and 40 percent oxygen, a ppO2 of 1.6 ata is reached at 99 fsw. Therefore, oxygen toxicity must be considered when diving a NITROX...

Ascent Procedures

After selecting the applicable decompression schedule, it is imperative that it be followed as closely as possible. Unless a Diving Medical Officer recommends a deviation and the Commanding Officer concurs, decompression must be completed according to the schedule selected. 9-6.1.1 Ascent Rate. Always ascend at a rate of 30 fpm ( 20 per 10 fsw). Minor variations in the rate of travel between 20 and 40 fsw minute are acceptable. Any variation in the rate of ascent must...

Name Plate Data

Conduct visual inspection of chamber to determine if ready for test Chamber Satisfactory _ Initials of Test Conductor _ Discrepancies from fully inoperative chamber equipment 2 Close inner door lock. With outer lock door open pressure inner lock to 100 fsw (45 psig) and verify that the following components do not leak (Note If chamber has medical lock, open inner door and close and secure outer door.) A. Shell penetrations and fittings 3. Increase inner lock pressure to 225 fsw (100 psig) and...

Pressure In Diving

Pressure is defined as a force acting upon a particular area of matter. It is typically measured in pounds per square inch (psi) in the English system and Newton per square centimeter (N cm2) in the System International (SI). Underwater pressure is a result of the weight of the water above the diver and the weight of the atmosphere over the water. There is one concept that must be remembered at all times any diver, at any depth, must be in pressure balance with the forces at that depth. The...

Opensea Deep Diving Records

Diving records have been set and broken with increasing regularity since the early 1900s 1915. The 300-fsw mark was exceeded. Three U.S. Navy divers, F. Crilley, W.F. Loughman, and F.C. Nielson, reached 304 fsw using the MK V dress. 1972. The MK 2 MOD 0 DDS set the in-water record of 1,010 fsw. 1975. Divers using the MK 1 Deep Dive System descended to 1,148 fsw. 1977. A French dive team broke the open-sea record with 1,643 fsw. 1981. The deepest salvage operation made with divers was 803 fsw...

Energy

The six basic types of energy are mechanical, heat, light, chemical, electromagnetic, and nuclear, and may appear in a variety of forms (Figure 2-4). Energy is a vast and complex aspect of physics beyond the scope of this manual. Consequently, this chapter only covers a few aspects of light, heat, and mechanical energy because of their unusual effects underwater and their impact on diving. 2-5.1 Conservation of Energy. The Law of the Conservation of Energy,...

Thermal Problems And Other Physiological Problems In Diving

Thermal problems arising from exposure to cold water pose the major consideration when planning operational dives and selecting equipment. The working diver commonly experiences heat loss during immersion and often expects to be uncomfortably chilled at the end of a dive. Bottom time limits may be determined by the diver's cold tolerance rather than by decompression considerations. The human body functions effectively within a relatively narrow range of internal temperature. The average, or...

Minimum Equipment

The face mask protects the diver's eyes and nose from the water. Additionally, it provides maximum visibility by putting a layer of air between the diver's eyes and the water. Face masks are available in a variety of shapes and sizes for diver comfort. To check for proper fit, hold the mask in place with one hand and inhale gently through the nose. The suction produced should hold the mask in place. Don the mask with the head strap properly adjusted, and inhale gently through...

T2

Transpose the formula for Charles's Gay-Lussac's law to solve for the final pressure (P2) 4. Substitute known values and solve for the final pressure (P2) P2 The pressure in the flask increased from 3,000 psig to 3,570.03 psia. Note that the pressure increased even though the flask's volume and the volume of the gas remained the same.

Diver Candidate Pressure Test

Navy diver candidates shall be physically qualified in accordance with the Manual of the Medical Department, Art. 15-66. Candidates shall also pass a pressure test before they are eligible for diver training. This test may be conducted at any Navy certified recompression chamber, provided it is administered by qualified chamber personnel. 22-7.1 Candidate Requirements. The candidate must demonstrate the ability to equalize pressure in both ears to a depth of 60 fsw. The candidate shall...

Disorders Of Higher Function And Consciousness

Divers may experience sensations while at depth which they would describe as dizziness, or in some situations may lose consciousness. The causes of these conditions are not always obvious and surfacing the diver may not be possible because of decompression obligations. Therefore, it is important to know what could cause these disorders in order to decide the possibility of injury to the diver. 19-5.1 Vertigo. The sensation of the diver spinning or the environment spinning is called vertigo....

Warning Do not use a malfunctioning compressor to pump divers breathing air or charge divers air storage flasks as this

Lubricants used in diver's air compressors shall conform to MIL-L-17331 (2190 TEP) for normal operations, or MIL-H-17672 (2135TH) for cold weather operations. Where the compressor manufacturer specifically recommends the use of a synthetic base oil in their compressor for production of breathing air, that manufacturer recommended synthetic base oil may be used in lieu of MIL-L-17331 or MIL-H-17672 oil. Oil shall be changed out on compressors in strict accordance with the PMS requirements...

Select Diving Technique

The three main types of air diving equipment used in U.S. Navy diving operations are (Figure 6-13) Figure 6-12. International Code Signal Flags. Figure 6-12. International Code Signal Flags. 2. MK 20 MOD 0 surface-supplied gear 3. MK 21 MOD 1 surface-supplied gear OPEN-CIRCUIT SCUBA Normal working limit 130 fsw Operational necessity 190 fsw OPEN-CIRCUIT SCUBA Normal working limit 130 fsw Operational necessity 190 fsw Normal working limit with EGS 60 fsw SURFACE-SUPPLIED DEEP-SEA GEAR (MK 21 MOD...

C2 Predatory Marine Animals

Shark attacks on humans are infrequent. Since 1965, the annual recorded number of shark attacks is only 40 to 100 worldwide. These attacks are unpredictable and injuries may result not only from bites, but also by coming in contact with the shark's skin. Shark skin is covered with very sharp dentine appendages, called denticles, which are reinforced with tooth-like centers. Contact with shark skin can lead to wide abrasions and heavy bleeding. 5C-2.1.1 Shark Pre-Attack Behavior....

Warning Cpr should not be initiated on a severely hypothermic diver unless it can be determined that the heart has

Wrap victim in a blanket (preferably wool). Place in an area protected from wind. If possible, place in a warm area (i.e. galley). 2. Active Place in a very warm space (i.e. engine room). 19-7.3 Physiological Effects of Exposure to Cold Water. In addition to hypothermia, other responses to exposure to cold water create potential hazards for the diver. The effect of these responses may be cumulative and magnified by underlying hypothermia. Diving Reflex Bradycardia. The Mammalian or diving...

Mixedgas Diving

Mixed-gas diving operations are conducted using a breathing medium other than air. This medium may consist of Nitrogen and oxygen in proportions other than those found in the atmosphere A mixture of other inert gases, such as helium, with oxygen. The breathing medium can also be 100 percent oxygen, which is not a mixed gas, but which requires training for safe use. Air may be used in some phases of a mixed-gas dive. Mixed-gas diving is a complex undertaking. A mixed-gas diving operation...

Saturation Decompression

Saturation decompression may be initiated by an upward excursion as long as the excursion remains within the limits permitted by the Unlimited Duration Excursion Tables. The alternative is to begin travel at the appropriate decompression rate without the upward excursion. Decompression travel rates are found on Table 15-9. Table 15-9. Saturation Decompression Rates. Table 15-9. Saturation Decompression Rates. 15-23.1 Upward Excursion Depth. The minimum depth to which the upward excursion may be...

NOTE Performance of a careful dip test during predive set up is essential to detect system leaks Additionally dive

18-2.5 Middle Ear Oxygen Absorption Syndrome. Middle ear oxygen absorption syndrome refers to the negative pressure that may develop in the middle ear following a long oxygen dive. Gas with a very high percentage of oxygen enters the middle ear cavity during the course of an oxygen dive. Following the dive, the oxygen is slowly absorbed by the tissues of the middle ear. If the Eustachian tube does not open spontaneously, a negative pressure relative to ambient may result in the middle ear...

Operational Characteristics of SSDS Surfacesupplied diving systems can be

Divided into two major categories lightweight full face mask (MK 20), and deep-sea (MK 21) gear. 6-7.3.1 Mobility. Surface-supplied gear allows the diver almost as much mobility as scuba. The primary use for deep-sea gear is bottom work in depths up to 190 fsw. 6-7.3.2 Buoyancy. The buoyancy associated with SSDS varies with the diving dress selected. Variable Volume Dry Suit (VVDS) provides the greatest buoyancy control (see paragraph 7-3.1.2), making it a desirable technique for working on...

Scuba Diving

The diving equipment developed by Charles and John Deane, Augustus Siebe, and other inventors gave man the ability to remain and work underwater for extended periods, but movement was greatly limited by the requirement for surface-supplied air. Inventors searched for methods to increase the diver's movement without increasing the hazards. The best solution was to provide the diver with a portable, self-contained air supply. For many years the self-contained underwater breathing apparatus...

Ascent To Altitude After Divingflying After Diving

Leaving the dive site may require temporary ascent to a higher altitude. For example, divers may drive over a mountain pass at higher altitude or leave the dive site by air. Ascent to altitude after diving increases the risk of decompression sickness because of the additional reduction in atmospheric pressure. The higher the altitude, the greater the risk. (Pressurized commercial airline flights are addressed in Note 3 of Table 9-5.) Table 9-5 gives the surface interval (hours minutes) required...

Planning The Operation

Planning surface-supplied mixed-gas dives involves many of the same considerations used when planning an air dive. Planning aspects that are unique to surface-supplied mixed-gas diving include the logistics of providing several different gas mixtures to the diver and the limitations on the duration of carbon dioxide absorption canisters in cold water. 14-2.1 Depth and Exposure Time. The normal operational limit for surface-supplied mixed-gas diving is 300 fsw. Within each decompression table...

Hygiene

Once a saturation dive begins, any illness that develops is likely to affect the entire team, reducing their efficiency and perhaps requiring the dive to be aborted. To minimize this possibility, the Saturation Diving Medical Officer should conduct a brief review of the diver's physical condition within 24 hours of compression. If an infectious process or illness is suspected, it shall be carefully evaluated by the Saturation Diving Medical Officer for possible replacement of the diver with a...

Equivalent Air Depth

The partial pressure of nitrogen in a NITROX mixture is the key factor determining the diver's decompression obligation. Oxygen plays no role. The decompression obligation for a NITROX dive therefore can be determined using the Standard Air Tables simply by selecting the depth on air that has the same partial pressure of nitrogen as the NITROX mixture. This depth is called the Equivalent Air Depth (EAD). For example, the nitrogen partial pressure in a 68 nitrogen 32 oxygen mixture at 63 fsw is...

Medical Aspects Of Closedcircuit Mixedgas

When using a closed-circuit mixed-gas UBA, the diver is susceptible to the usual diving-related illnesses (i.e., decompression sickness, arterial gas embolism, barotrauma, etc.). Volume 5 gives in-depth coverage of all diving-related illnesses. For closed-circuit mixed-gas UBAs there are special medical considerations that must be addressed. 17-11.1 Central Nervous System (CNS) Oxygen Toxicity. Toxic effects may result from breathing oxygen at high partial pressures. CNS oxygen toxicity is...

Hyperventilation

Hyperventilation is the term applied to breathing more than is necessary to keep the body's carbon dioxide tensions at proper level. Hyperventilation (whether voluntary or involuntary) has little effect on the body's oxygen levels, but abnormally lowers the partial pressure of carbon dioxide in the blood and delays the normal urge to breathe. If the carbon dioxide stores are ventilated below the stimulus level, there will be little urge to breathe until late in the breathhold. The oxygen...

Nitrox Mixing

NITROX mixing can be accomplished by a variety of techniques to produce a final predetermined nitrogen-oxygen mixture. The techniques for mixing NITROX are listed as follows 1. Continuous Flow Mixing. There are two techniques for continuous flow mixing a. Mix-maker. A mix-maker uses a precalibrated mixing system that proportions the amount of each gas in the mixture as it is delivered to a common mixing chamber. A mix-maker performs a series of functions that ensures accurate mixtures. The...

Heat Energy In Diving

Heat is crucial to man's environmental balance. The human body functions within only a very narrow range of internal temperature and contains delicate mechanisms to control that temperature. Heat is a form of energy associated with and proportional to the molecular motion of a substance. It is closely related to temperature, but must be distinguished from temperature because different substances do not necessarily contain the same heat energy even though their temperatures are the same. Heat is...

Decompression Sickness

Decompression sickness results from the formation of bubbles in the blood or body tissues, and is caused by inadequate elimination of dissolved gas after a dive or other exposure to high pressure. Decompression sickness may also occur with exposure to subatmospheric pressures (altitude exposure), as in an altitude chamber or sudden loss of cabin pressure in an aircraft. In certain individuals, decompression sickness may occur from no-decompression dives, or decompression dives even when...

Water Entry And Descent

Jon Lindbergh Diver Chicago

The divers are now ready to enter the water, where their scuba shall be given another brief inspection by their dive partners or tenders prior to descent. 7-6.1 Water Entry. There are several ways to enter the water, with the choice usually determined by the nature of the diving platform (Figure 7-8a and Figure 7-8b). Whenever possible, entry should be made by ladder, especially in unfamiliar waters. Several basic rules apply to all methods of entry Look before jumping or pushing off from the...

Oxygen Rebreather

SEAL team members are trained to operate in all of these environments. They qualify as parachutists, learn to handle a range of weapons, receive intensive training in hand-to-hand combat, and are expert in scuba and other swimming and diving techniques. In Vietnam, SEALs were deployed in special counter-insurgency and guerrilla warfare operations. The SEALs also participated in the space program by securing flotation collars to returned space capsules and assisting astronauts...

Standard Navy Syntax

Since this manual will form the technical basis of many subsequent instructions or directives, it utilizes the standard Navy syntax as pertains to permissive, advisory, and mandatory language. This is done to facilitate the use of the information provided herein as a reference for issuing Fleet Directives. The concept of word usage and intended meaning that has been adhered to in preparing this manual is as follows Shall has been used only when application of a procedure is mandatory. Should...

Salvage Diving

Navy divers were plunged into the war with the Japanese raid on Pearl Harbor. The raid began at 0755 on 7 December 1941 by 0915 that same morning, the first salvage teams were cutting through the hull of the overturned battleship USS Oklahoma to rescue trapped sailors. Teams of divers worked to recover ammunition from the magazines of sunken ships, to be ready in the event of a second attack. The immense salvage effort that followed at Pearl Harbor was highly successful....

Diving At High Altitudes

Because of the reduced atmospheric pressure, dives conducted at altitude require more decompression than identical dives conducted at sea level. Standard air decompression tables, therefore, cannot be used as written. Some organizations calculate specific decompression tables for use at each altitude. An alternative approach is to correct the altitude dive to obtain an equivalent sea level dive, then determine the decompression requirement using standard tables. This procedure is commonly known...

Arterial Gas Embolism

Arterial gas embolism, sometimes simply called gas embolism, is caused by entry of gas bubbles into the arterial circulation which then act as blood vessel obstructions called emboli. These emboli are frequently the result of pulmonary barotrauma caused by the expansion of gas taken into the lungs while breathing under pressure and held in the lungs during ascent. The gas might have been retained in the lungs by choice (voluntary breathholding) or by accident (blocked air passages). The gas...

NOTE Usage for three divers is computed even though the standby would not normally be using gas for the entire 15

15-8.2 Emergency Gas Supply Duration. The gas computation in paragraph 15-8.1 is used to determine excursion limits based on diver's gas storage. The diver's emergency gas supply (EGS) duration should also be calculated using the following formulas psi available for use psi (cylinder) - mmp psi (Available) + 14.7 scf gas available c --j-4-7 --x fv psi (obp) over-bottom pressure required for specific UBA mmp minimum manifold pressure acfm actual cubic feet per minute at excursion depth required...

Gases In Diving

Knowledge of the properties and behavior of gases, especially those used for breathing, is vitally important to divers. 2-10.1 Atmospheric Air. The most common gas used in diving is atmospheric air, the composition of which is shown in Table 2-2. Any gases found in concentrations different than those in Table 2-2 or that are not listed in Table 2-2 are considered contaminants. Depending on weather and location, many industrial pollutants may be found in air. Carbon monoxide is the most commonly...

Daltons

Dalton's law states that the total pressure exerted by a mixture of gases is equal to the sum of the pressures of the different gases making up the mixture, with each gas acting as if it alone occupied the total volume. The pressure contributed by any gas in the mixture is proportional to the number of molecules of that gas in the total volume. The pressure of that gas is called its partial pressure (pp), meaning its part of the whole. The formula for expressing Dalton's law is Sample Problem...

P1v1 P2v2

The formula for expressing the general gas law is ----- ----- Where Two simple rules must be kept in mind when working with the general gas law There can be only one unknown value. The equation can be simplified if it is known that a value remains unchanged (such as the volume of an air cylinder) or that the change in one of the variables is of little consequence. In either case, cancel the value out of both sides of the equation to simplify the computations. Sample Problem 1. Your ship has...

Mixedgas Diving Equipment

Fads Iii Mixed Gas System Fmgs

There are several modes of diving that are characterized by the diving equipment used. The following descriptions outline capabilities and logistical requirements for various mixed-gas diving systems. 13-8.1 Minimum Required Equipment. Minimum required equipment for the pool phase of dive training conducted at Navy diving schools may be modified as necessary. Any modifications to the minimum required equipment listed herein must be noted in approved lesson training guides. 1. MK 21 MOD 1 helmet...

Barotrauma

Barotrauma, or damage to body tissues from the mechanical effects of pressure, results when pressure differentials between body cavities and the hydrostatic pressure surrounding the body, or between the body and the diving equipment, are not equalized properly. Barotrauma most frequently occurs during descent, but may also occur during ascent. 19-4.1 Squeeze. Squeeze during descent occurs when gas in a cavity is compressed. The types of squeeze most frequently encountered in diving are Middle...

Exceptional Exposure Dives

Exceptional exposure dives are those dives in which the risk of decompression sickness, oxygen toxicity, and or exposure to the elements is substantially greater than on normal working dives. Decompression schedules for exceptional exposure dives are contained in the Standard Air Decompression Table. These exceptional exposure schedules are intended to be used only in emergencies, such as diver entrapment. Exceptional exposure dives should not be planned in advance except under the most unusual...

Scuba Use During World War II Although closedcircuit equipment was re

Ww2 Diving Suit

Stricted to shallow-water use and carried with it the potential danger of oxygen toxicity, its design had reached a suitably high level of efficiency by World War II. During the war, combat swimmer breathing units were widely used by navies on both sides of the conflict. The swimmers used various modes of underwater attack. Many notable successes were achieved including the sinking of several battleships, cruisers, and merchant ships. 1-3.5.1 Diver-Guided Torpedoes. Italian divers, using...

Diver Tender

6-9.10.1 Diver Tender Responsibilities. The tender is the surface member of the diving team who works closely with the diver on the bottom. At the start of a dive, the tender checks the diver's equipment and topside air supply for proper operation and dresses the diver. Once the diver is in the water, the tender constantly tends the lines to eliminate excess slack or tension (certain UWSH tasking may preclude this requirement, e.g., working in submarine ballast tanks, shaft lamination, dry...

Water Depth and Sound In shallow water or in enclosed spaces reflections and

Reverberations from the air water and object water interfaces produce anomalies in the sound field, such as echoes, dead spots, and sound nodes. When swimming in shallow water, among coral heads, or in enclosed spaces, a diver can expect periodic losses in acoustic communication signals and disruption of acoustic navigation beacons. The problem becomes more pronounced as the frequency of the signal increases. Because sound travels so quickly underwater (4,921 feet per second), human ears cannot...

NOTE Omitted decompression is a dangerous situation Procedures for dealing with this situation are discussed in Chapter

9-5.2 Selection of Decompression Schedule. The decompression schedules of all the tables are usually given in 10-foot depth increments and 10-minute bottom time increments. Depth and bottom time combinations from dives, however, rarely match the decompression schedules exactly. To ensure that the selected decompression schedule is always conservative, always select the schedule depth equal to or next greater than the maximum depth of the dive and always select the schedule bottom time equal to...

Omitted Decompression

Certain emergencies, such as uncontrolled ascents, an exhausted air supply, or bodily injury, may interrupt or prevent required decompression. If the diver shows symptoms of decompression sickness or arterial gas embolism, immediate treatment using the appropriate oxygen or air recompression treatment table is essential. Even if the diver shows no symptoms, omitted decompression must be addressed in some manner to avert later difficulty. Table 21-3 summarizes management of asymptomatic Omitted...

Equipment Authorized for Navy Use Equipment procured for use in the US

Navy has been tested under laboratory and field conditions to ensure that it will perform according to design specifications. A vast array of equipment and tools is available for use in diving operations. The NAVSEA 00C Diving Equipment Authorized for U.S. Navy Use (ANU) list identifies much of this equipment and categorizes diving equipment authorized for U.S. Navy use. 6-8.2 Air Supply. The quality of diver's breathing air is vitally important. Air supplies provided to the diver in tanks or...

Pulmonary Overinflation Syndromes

Pulmonary overinflation syndromes are disorders that are caused by gas expanding within the lung. The disorders encountered in diving are arterial gas embolism, mediastinal and subcutaneous emphysema, and pneumothorax. Normally, only arterial gas embolism (AGE) requires recompression therapy (Chapter 20, paragraph 20-2). 19-3.1 Mediastinal and Subcutaneous Emphysema. Mediastinal emphysema is caused by gas expanding in the tissues behind the breast bone. Symptoms include mild to moderate pain...

Thermal Protection System

All saturation diver life-support systems include diver thermal protection consisting of a hot water suit and a breathing gas heater. The thermal protection is designed to minimize the diver's heat loss caused by helium's high thermal conductivity. Helium conducts heat away from the body rapidly and causes a significant heat loss via the diver's breathing gas. The diver's metabolic rate may not be great enough to compensate for the heat loss when breathing cold gas, resulting in a drop in body...

Surfacesupplied Heliumoxygen Emergency Procedures

In surface-supplied mixed-gas diving, specific procedures are used in emergency situations. The following paragraphs detail these procedures. Other medical physiological factors that surface-supplied mixed-gas divers need to consider are covered in detail in Volume 5. The U.S. Navy Treatment Tables are also presented in Volume 5. 14-4.1 Bottom Time in Excess of the Table. In the rare instance of diver entrapment or umbilical fouling, bottom times may exceed 120 minutes, the longest value shown...

Bibs

Atmospheric Monitoring Gas Supply Communications Air-driven, replaceable scrubber, canister fits in TRC Med Lock 2 masks - oxygen and air supply -overboard dump Oxygen and Carbon Dioxide Analyzer Primary and secondary air and O2 Sound-powered phone 22-2.5.1 Labeling. All lines should be identified and labeled to indicate function, content and direction of flow. The color coding in Table 22-1 should be used. Table 22-1. Recompression Chamber Line Guide. Table 22-1. Recompression Chamber Line...

Co2

Another physical effect of partial pressures and kinetic activity is that of gas diffusion. Gas diffusion is the process of intermingling or mixing of gas molecules. If two gases are placed together in a container, they will eventually mix completely even though one gas may be heavier. The mixing occurs as a result of constant molecular motion. An individual gas will move through a permeable membrane (a solid that permits molecular transmission) depending upon the partial...

Surface Decompression

Surface decompression is a technique for fulfilling all or a portion of a diver's decompression obligation in a recompression chamber instead of in the water, significantly reducing the time that a diver must spend in the water. Also, breathing oxygen in the recompression chamber reduces the diver's total decompression time. Other variations will be handled in accordance with paragraph 9-6.2. Surface decompression offers many advantages that enhance the divers' safety. Shorter exposure time in...

Rnt Exception Rule

If a breathing medium containing helium was breathed at any time during the 12-hour period immediately preceding a dive, use HeO2 as the previous breathing medium. 2. If 100 percent oxygen rebreathers are used on a dive in conjunction with other breathing gases, treat that portion of the dive as if 0.7 ATA O2 in N2 was breathed. 3. If both air and 0.7 ATA O2 in N2 are breathed during a dive, treat the entire dive as an air dive. If the 0.7 ata O2 in N2 is breathed at depths 80 fsw or deeper,...

The Respiratory System

Every cell in the body must obtain energy to maintain its life, growth, and function. Cells obtain their energy from oxidation, which is a slow, controlled burning of food materials. Oxidation requires fuel and oxygen. Respiration is the process of exchanging oxygen and carbon dioxide during oxidation and releasing energy and water. 3-4.1 Gas Exchange. Few body cells are close enough to the surface to have any chance of obtaining oxygen and expelling carbon dioxide by direct air diffusion....

Navseainst 105603

Diving Alterations on Diver Life Support Systems (DLSS) NAVSEA Technical Manual (S0600-AA-PR0-010) NAVSEA Technical Manual (0994-LP-007-8010) Volume 1, (0994-LP-007-8020) Volume 2 U.S. Navy Underwater Work Techniques Manual NAVSEA Technical Manual (SS500-HK-MM0-010.) MK 3 MOD 0 Light Weight Diving System Operating and Maintenance NAVSEA Technical Manual (SS500-AW-MMM-010) MK 6 MOD 0 Transportable Recompression Chamber System Operating and Maintenance NAVSEA Technical Manual (SS600-AH-MMA-010)...

Neurological Examination Checklist

Neurological Checklist

The following procedures are adequate for preliminary examination. Figure 5A-1a can be used to record the results of the examination. Figure 5A-1a. Neurological Examination Checklist (sheet 1 of 2). Figure 5A-1a. Neurological Examination Checklist (sheet 1 of 2). Figure 5A-1b. Neurological Examination Checklist (sheet 1 of 2). Figure 5A-1b. Neurological Examination Checklist (sheet 1 of 2). 5A-3.1 Mental Status. This is best determined when you first see the patient and is characterized by his...

Closedcircuit Oxygen Exposure Limits

Navy closed-circuit oxygen exposure limits have been extended and revised to allow greater flexibility in closed-circuit oxygen diving operations. The revised limits are divided into two categories Transit with Excursion Limits and Single Depth Limits. 18-4.1 Transit with Excursion Limits Table. The Transit with Excursion Limits (Table 18-4) call for a maximum dive depth of 20 fsw or shallower for the majority of the dive, but allow the diver to make a brief excursion to depths as...

Warning Skipbreathing may lead to hypercapnia and shall not be practiced

Increased breathing resistance results from the design of the equipment and increased air density. For normal diving, a marked increase of breathing resistance should not occur until the primary air supply has been almost depleted. This increase in breathing resistance is a signal to the diver to activate the reserve air supply and to begin an ascent with the partner immediately. When equipped with a submersible bottle gauge, the diver shall monitor his air supply pressure and must terminate...

Thermal Problems And Other Physiological Problems In Diving346

3-12.1 Regulating Body 3-12.2 Excessive Heat Loss 3-12.2.1 Internal Temperature 3-12.2.2 Effects of Exercise on 3-12.2.3 Symptoms of 3-12.3 Excessive Heat 3-12.3.1 Heat Stress 3-12.3.3 Symptoms of 3-12.3.4 Impact of Dive Time on 3-12.3.5 Preventing 3-12.4 3-12.4.1 Causes of 3-12.4.2 Preventing 3-12.5 3-12.5.1 Symptoms of 3-12.5.2 Causes of 3-12.5.3 Preventing