MS 105 – Basic dive equipment

1. MS 105 – Basic dive equipment

2. Basic Equipment As divers you will need to know the • FUNCTION • FEATURES • SELECTION • CARE of your basic equipment

3. Mask Function – provides a layer of air between the eyes and water to restore vision. ***Note - Underwater objects appear ~33% larger and 25% closer. This is due to Snell’s Law of Refraction – the refraction of light moving from one medium (water) to another (air inside your mask) and the differing of speed of light in varying media.

4. Mask Features • Safety or tempered glass – not plastic. Held in place by plastic ring for easy replacement. • Low volume – easy to equalize pressure and to clear, especially for skin diving. • Wide view/Side lens • Double skirt – for face seal • Nose pouch/finger pockets – to aid in equalizing pressure • Split strap • Prescription lenses (optically corrected)– can be mounted on inside of the mask or special lenses made. Contacts can be worn if eyes are closed when mask is flooded. • Clear Silicone – + clear lets more light in - glare (opaque)

5. Mask Selection – fit and comfort are the most important. Try a variety on before making decision. Hold to face and inhale. Try with reg. in mouth. Care • Avoid extended exposure to direct sunlight • Rinse after use, use soapy water if you have sunscreen residue build up. ¿ ¿ ¿ ¿ Defogger – Sí o no??? Cost ≈ $25 - $80 & ↑

6. Snorkel Function – simple breathing tube which allows divers to breath with face in water. It is tiring to lift head. Features – • J-shaped most efficient snorkle has shortest, smoothest flow of air. • Flex-type + easy to get in mouth -restricts air flow and traps water which facilitates fungal growth • Angled/Wrap around fits close to face, less drag • Shot gun purge valve clears ‘most’ of snorkle • Big bore improved air flow ~ 7/8” diameter. • Contoured mouthpiece moldable teeth grips • Snorkel tab/keeper on left side of mask

7. Snorkel Selection – do not get one that is too small/large of a diameter Care - Rinse, don’t crush Cost ≈ $15 - $40

9. Fins Function – provide increased mobility and efficiency in the water. More power and thrust with minimum effort. Features – • Adjustable strap – should have locking devices • Vented fins – water flows in areas of resistance • Split fin – more thrust underwater, not always on surface may have less turning ability.

10. What to consider when selecting fins • Construction – durability pvc, rubber, etc • Heels – open vs. closed • Size and stiffness - largely dictate a fin's efficiency • Other factors include skill level and conditioning • Ability Level

11. Fins selection criteria – • Based on diver’s size, strength and intended use • Fit and comfort, no cramping. If dive shop has a pool try them out. Care • Avoid straining straps when donning fins • Same as other rubber products Cost ≈ $30 - $120

12. Booties • Nylon covered neoprene • Come in various thickness – 1/4” minimum (7mm to 10mm) • Come with various soles • NO ZIPPERS – get filled with sand

13. Features: Dive Knife • Handle • Blade – non-corrosive • Serrated edge • Line cutter • Sheath • Straps

14. Underwater Watches • Minimum for monitoring bottom time • Must be water resistant well over diving depth (100m+) • Analog vs. digital • Analog • Screw down crown • Heavy construction / self winding • Luminous dial • Bezel *** costs to replace batteries • Digital • Light • Must be set • More expensive • More subject to failure Seiko $120-250 Casio $25-60 Casio $25 Freestyle $35

15. Where to purchase Monterey - Monterey Bay Dive Center - http://www.montereyscubadiving.com/ Aquarius Dive Shop - http://www.aquariusdivers.com/ Bamboo Reef - http://www.bambooreef.com/ Santa Cruz – Adventure sports - http://www.asudoit.com/diving/index.html Aqua Safaris - http://www.aquasafaris.com/ Heat Wave (custom) - http://www.heatwavewetsuits.com/hwhomepage.html Bay Area– San Jose – Any Water sports Dive shop 408 244 4433 Oakland – Steele’s Phone: (510) 655-4344 Worth checking out http://www.officialdivegearpage.com/ http://www.montereyexpress.com/DiveLinks.htm *** SCUBA MAX

16. Bottom Timer • Current Depth • Maximum Depth • Total Dive Time • Water and Air Temperature • Rate of ascent- some more $$ models • Surface Interval • Logbook – some more $$ models KEY ADVANTAGE MOST TIMERS START AUTOMATICALLY

17. Capillary: Depth Gauges Air/Oil-filled Bourdon tube: • Nonlinear scale – harder to read at deeper depths • Bubbles can invalidate readings • Open – debris can block tube • A c-shaped or spiral tube used in pressure (depth) gauges. Increased pressure acts on the tube by changing its shape. This movement is used to change the position of a gauge needle • Some have reset needle which marks deepest depth if zeroed at start of dive Digital: • Based on above gauge type linked to display with microchip technology

18. Movement gauge – flattened helical tube open at one end and pressure uncurls it. Free end attached to a needle. • Open – tube end exposed to water • Sealed Tube – tube is fluid filled and end plugged with rubber diaphragm • Oil-filled Bourdon tube –both ends • plugged and tube in oil • VS • Diaphragm – does not use bourdon movement, only a diaphragm Bourdon Instruments

19. Features: Submersible Pressure Gauges • Attaches to first stage with high pressure hose and provides continuous readout of pressure • First came out in 1954 but nobody used it. resurfaced in 1966, now standard/required equipment. • Fits into console • Luminous • Readable at low pressures ‘red zone’ • At 500psi, have accuracy range of +/- 35-100psi

20. Compass Features: • Lubber line • Bezel • Readability • Fits into console or on arm • Luminous dial Cost ~35-40.00$$

21. Weight Belt Features: • Quick release • Lead Weight • Many weights and sizes (plastic coated, lead shot i.e. “soft vs. hard weight”) • Clips • Harness

22. Exposure Suits (wet vs. dry) Features: • Wet vs. Dry • Thickness – 7 mm(minimum for central coast north) -10mm • Material – Neoprene  Skin-in vs. plush/lycra • Two piece vs. one piece • Attached hood vs. non-attached • Zipper placement

23. Modern BCD – Buoyancy Compensating Device Features: • Large volume • Mouth piece for oral inflation • Power inflator • Overpressure relief valve • Shoulder straps • D-rings • Integrated weights • Gear snaps

24. Gear Bag, Duffle or Box • One that can hold all dive gear VS. Action Packer Rollie bag

25. Mesh Goodie Bag • One that can hold fins, mask snorkle

26. Save-a-dive Kit • O-rings • Extra straps (fin and mask) • Extra mouth piece • Cable / Zip ties • Pencils • 1st stage port plugs • Scuba tool • Mouth piece

27. Dive Slate • PVC Plastic • Clip • Pencil on bungie or string • Research Slate allows addition of paper MLML Slates -$15.00

28. Safety Sausage • Roll-up sausage for BC pocket • Increased visibility on surface