Are you diving with too much weight? Many divers are.
Maybe your body mass has changed, or maybe you most frequently dive in cold water and don’t reduce your weight enough when you switch to warm water. But the most common reason is: you’ve always used too much weight.
When I was a beginner diver, divemasters would always look at me funny when I asked for eight kilograms (18 lbs) of weight while wearing a three-millimeter wetsuit (I weigh about 52kg/115 lbs.). “This is how much weight I always use,” I’d say with a shrug.
I felt confident asking for that much weight, because that’s how much weight I used in my PADI Open Water Diver class. When the instructor had us do a buoyancy check at the surface, there I was, floating at eye level like a champ. When I exhaled, I descended. Ergo, I was perfectly weighted.
I didn’t realize I was unconsciously holding my breath (just a little) throughout the dive. I didn’t do it on purpose. As every certified diver knows, the number one rule of scuba diving is to breathe continuously and never hold your breath. But my anxiety around scuba diving kept me from fully relaxing.
As a result, I carried three-and-a-half kilograms (eight pounds) more weight than I needed. That amount of weight is equivalent to about four liters (one gallon) of water.
Imagine carrying four liters (one gallon) of something around for 30 to 60 minutes. Unless you’re extremely fit, you’ll be breathing heavy before long — which leads me to the first problem of diving overweighted.
#1 You Use up the Air in Your Tank Faster
As described above, the extra kilograms/pounds you’re carrying force your body to work harder than necessary. Extra exertion requires more oxygen, so you breathe heavier and drain your tank (cylinder) faster.
If you want to spend more time underwater, ask your PADI Instructor about a Peak Performance Buoyancy course. It’s a great way to drop a few kilograms/pounds and one of the easiest ways to improve your air consumption while scuba diving.
#2 An Overweighted Diver Is a “Disaster Diver”
Divers who wear too much weight often plunge straight to the bottom. I’ve seen overweighted divers crash onto the reef and drop onto divers who entered the water a few moments before.
Throughout the dive, divers wearing too much weight often have buoyancy problems. They swim along, not realizing they’ve descended – until they kick something. By then, the damage is already done.
When I was a new diver, I knew my buoyancy wasn’t very good, so I stayed about four meters (15 feet) above the reef. Divemasters would signal me to look at things, but I’d wave them off because I knew I’d struggle to hold my position in the water. Want to see a seahorse? No, thanks. Harlequin shrimp? Not interested. I’m kidding, of course. I wanted to see those things more than anything.
#3 Extra Weight = Increased Risk
In addition to being a hazard to marine life and other divers, people who wear too much weight put themselves at risk. Divers Alert Network (DAN) tracks diving incidents from around the world. Nearly 90% are caused by diver error.
As mentioned above, wearing too much weight means your body has to work harder. If you’re not as fit as you used to be, kicking into a current can turn a challenging swim into a medical emergency.
When you’re diving with too much weight, an equipment failure, such as a BCD that fails to inflate or a dropped weight pocket can become hazardous in a hurry. I recently had a weight pocket fall out during a dive, but I was able to ascend slowly and safely. If the same thing had happened when I was diving overweighted, I could have ended up with Decompression Sickness (DCS) or another diving injury caused by a rapid ascent.
Are You Diving With Too Much Weight?
Here are a few signs you may be diving with too much weight.
- At the start of the dive, you descend faster than everyone else.
- Scuba diving makes you feel exhausted .
- You add/dump air to your BCD frequently throughout the dive (a dozen times or more).
Frequent buoyancy adjustments are a red flag that you’re diving overweighted. When you dive with too much weight, you have to put more air in your BCD, about one pint per half kilo/pound. More air in your BCD means greater buoyancy fluctuations throughout the dive because the air expands and contracts as you ascend and descend.
How to Know If You’re Properly Weighted
The amount of weight you need for scuba diving is somewhat personal. Two people who weigh the same may need different amounts of weight depending on their:
- Body Composition – People with a higher percentage of body fat need more weight.
- Exposure Protection – Thick wetsuits and dry suits require more weight than a shorty.
- Tank (Cylinder) – Steel tanks (formally called cylinders) are typically negatively buoyant throughout the dive; aluminum tanks can start negative and become positive.
Scuba Diving Weight Calculator
Both DAN and Scuba Diving magazine have helpful articles about how much weight divers need with different scuba configurations. If you’re diving with the most common scuba cylinder (an 11-liter aluminum 80) in saltwater, here’s a quick way to estimate how much weight to use.
Start with:
- 10% of your body weight if wearing a full wetsuit (5-7mm).
- For a 3mm wetsuit, you may only need 5%
- If you’re wearing a dry suit, you may need 15% (or more)
Next, add two kilograms (four to five pounds) to offset the buoyancy of the tank at the end of the dive.
Then, do a buoyancy check.
At the surface, you should float at eye level while holding a full breath. When you exhale, you should descend slowly – not drop to the bottom like a rock.
To check your buoyancy at the end of a dive, hand off weights to your buddy and see if you can still descend when you exhale. Be careful not to go deeper than six meters (20 feet).
Enjoy Longer, Safer Dives
If you want to enjoy longer, more relaxed dives, the Peak Performance Buoyancy course is well worth it. You can complete the course in just one or two days. Most divers are pleasantly surprised by how much their diving skills and confidence improve in a short period of time.
