MS 105 – Basic dive equipment

Basic Equipment

• As divers you will need to know the

FUNCTION

•

FEATURES

•

SELECTION

•

CARE

of your basic equipment

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.

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)

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 & ↑

Snorkel

Function

–

simple

breathing tube which allows divers to breath with face in water. It is tiring to lift head.

Features

– • J-shaped air.

 most efficient snorkle has shortest, smoothest flow of • Flex-type  + easy to get in mouth -restricts air flow and traps water which facilitates fungal growth • Angled/Wrap around • Shot gun   fits close to face, less drag 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

Snorkel

Selection

– do not get one that is too small/large of a diameter Care - Rinse, don’t crush

Cost ≈ $15 - $40

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.

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

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

Fins

Booties

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

Dive Knife

Features:

• Handle • Blade – non-corrosive • Serrated edge • Line cutter • Sheath • Straps

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 Seiko $120-250 Casio $25-60 *** costs to replace batteries – Digital » Light » Must be set » More expensive » More subject to failure Casio $25 Freestyle $35

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

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

Depth Gauges Capillary:

• Nonlinear scale – harder to read at deeper depths • Bubbles can invalidate readings • Open – debris can block tube •

Air/Oil-filled Bourdon 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

Bourdon Instruments

• 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

Submersible Pressure Gauges

Features:

• 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

Compass

Features:

• Lubber line • Bezel • Readability • Fits into console or on arm • Luminous dial Cost ~35-40.00$$

Weight Belt

Features:

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

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

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

Gear Bag, Duffle or Box

• One that can hold all dive gear Rollie bag Action Packer VS.

Mesh Goodie Bag

• One that can hold fins, mask snorkle

Save-a-dive Kit

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

Dive Slate

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

Safety Sausage

• Roll-up sausage for BC pocket • Increased visibility on surface