Chapter 2 Scuba Diving Tanks / Air Cylinders Valves Buoyancy Compensators Weight Systems Regulators Datalog / Dive Log Dive Accessories 2-1

Objectives Discuss the differences in the equipment’s function from snorkeling to scuba diving. Define all the necessary components that comprise the scuba system. Introduce some accessories for consideration. Discuss the divelog or datalog as a legal document to verify training. 2-2

Buoyancy Compensators Purpose Types Front Mount or Snorkel Vest Back Mount Jacket Style Advanced Design Construction Features Oral Inflator Valve Automatic Inflator Dump Valve/ Deflators Pockets Adjustment and Fit Maintenance and Storage 2-3

Scuba Tanks Purpose Types Maintenance and Storage Size Materials Coatings Selection Maintenance and Storage 2-4

Scuba Tanks Tank Markings Hydro Testing (5/3-10%) Government Approved Type of Material Working Pressure Tank Volume Serial Number Manufacturer Hydro Date VIP Hydro Testing (5/3-10%) 2-5

Scuba Tanks Valves Purpose Types Features Maintenance K, J DIN O ring Burst Disc Maintenance 2-6

Regulators First Stage Second Stage Maintenance and Storage Features Downstream Pilot Valve Features Materials Mouthpiece Purge Valve Exhaust Valve Adjustments Maintenance and Storage Post Dive Annual Service Transportation and Storage 2-7

Alternate Air Sources Purpose Types Redundant Air System Octopus Integrated with Power Inflator Redundant Air System Maintenance and Storage 2-8

SPG (Submersible Pressure Gauge) Instruments SPG (Submersible Pressure Gauge) Purpose Air Supply Types Analog Digital / LCD Wireless 2-9

Instruments Depth Gauge Purpose Types Maintenance / Storage Capillary Oil Filled Open Bourdon Tube Diaphragm Maintenance / Storage 2-10

Instruments Timing Device Purpose Types Features Watch Dive Timer Features Maintenance and Storage 2-11

Instruments Compass Purpose Types Features Maintenance and Storage Bezel Card, Needle Side Window Numerical Markings Maintenance and Storage 2-12

Dive Computers Purpose and Function Features Pros and Cons Selection Transportation and Storage Maintenance 2-13

Datalog/Dive Log Purpose Datalog and Features Pre-Dive Checklists Training Record 2-14

Accessories Dive Flag or Float Whistle Signal Lights Underwater Lights Purpose Types Use Whistle Location Signal Lights Underwater Lights Types Maintenance Dive Knife Purpose Location Thermometer Slate Equipment Bag Spare Parts Kit 2-15

Discussion Questions/Review List some of the features that can be found on a buoyancy compensator. Describe how a two stage regulator works. In addition to the second stage, what other items can be attached to the first stage of the regulator? What gauges should the diver have in order to dive safely? Explain the difference between a “ J" Valve, a "K" Valve, and a "DIN" Valve. What are the two types of scuba cylinder inspections, and how often should they be performed? Describe how a dive partner might perform a pre-dive safety check. Describe how a diver clears water from the mask. In an effort to establish positive buoyancy, how would a diver release his weight belt in the water? 2-16

Summary Public Safety Diving is a rewarding activity once you begin to get comfortable with the necessary techniques and equipment. Getting to know your team’s equipment, training with it and the proper organization and care will all lead to a more efficient and effective diver and dive operation. 2-17