Scuba gear explained: what each piece does, and renting vs buying

TUREFF• •0

A full scuba set looks complicated, but it breaks down into a few pieces, each with a simple job. This guide explains what they do, which ones are worth owning first and how to look after them.

Mask

A mask puts an air space in front of your eyes so you can see clearly underwater. It must cover your nose so you can equalise it. Fit matters more than anything else: hold it against your face without the strap, breathe in gently through your nose, and it should stay put. A mask that leaks or fogs spoils a dive, which is why it is often the first thing people buy. Prescription lenses are available for many masks if you wear glasses.

Fins

Fins turn small leg movements into propulsion. There are two broad kinds:

Full-foot fins, worn barefoot, common in warm water.
Open-heel fins with an adjustable strap, worn over boots, better for shore entries, rocky ground and cooler water.

Exposure suit

Water draws heat from your body much faster than air, so you will get colder than you expect.

Rash guards and skins protect from sun and stings in very warm water.
Wetsuits trap a thin layer of water that your body warms. Thicker neoprene is warmer but more buoyant and stiffer.
Drysuits keep you dry with air or undergarments for warmth. They need their own training.

Ask the local dive centre what thickness people actually wear in that season.

BCD (buoyancy control device)

The BCD is the jacket or harness that holds your tank. You add air to it from the tank to float or hover, and let air out to descend. Good buoyancy control is the skill that most separates comfortable divers from struggling ones. Most BCDs also hold integrated weights or have pockets for them.

Regulator

The regulator reduces the high pressure in the tank to a pressure you can breathe. A set includes:

the first stage, which attaches to the tank
the second stage, the mouthpiece you breathe from
an alternate air source, a spare second stage for your buddy in an emergency
a pressure gauge showing how much air is left, unless that reading is sent wirelessly to a computer

Dive computer

A dive computer tracks your depth and time and calculates how long you can safely stay, warns you if you ascend too fast and times your safety stop. Many divers buy one early because it is personal: it keeps your dive history, and using one you know well is safer than learning a rental unit on every trip.

Weights

Your body, wetsuit and BCD float. Lead weights, on a belt or in the BCD, offset that. Too much weight makes you work harder; do a weight check with an instructor and note the result in your logbook.

Renting vs buying

A sensible order for many divers:

Buy first: mask, snorkel if you use one, and possibly fins and a computer. These are personal and easy to travel with.
Rent at first: BCD, regulator and tanks, until you know how often and where you will dive.
Buy later: a regulator and BCD once you dive regularly, so you know the kit you are breathing from and how it has been serviced.

Renting is perfectly normal for travelling divers. Check rental kit carefully before each dive and say if anything feels wrong.

Looking after your gear

Rinse everything in fresh water after diving, especially after salt water.
Dry it out of direct sunlight, which degrades rubber and neoprene.
Keep the regulator's dust cap on during rinsing so water does not enter the first stage.
Have regulators and BCDs serviced on the schedule the manufacturer recommends, by a qualified technician.
Store wetsuits on a wide hanger rather than folded.

What was the first piece of gear you bought, and would you buy it again? Share your experience or questions in the comments.