Understanding Decompression Sickness and How to Prevent It
Learn what causes decompression sickness (the bends), how to spot early symptoms, and the essential steps divers should take to prevent it.
SAFETY WHILE DIVING
Understanding Decompression Sickness and How to Prevent It
If you’ve ever heard of “the bends,” then you’ve heard of decompression sickness (DCS). This potentially serious condition affects divers who ascend too quickly, causing nitrogen bubbles to form in their tissues and bloodstream. While it can be dangerous, DCS is highly preventable with proper dive planning, awareness, and adherence to safety protocols.
What Causes Decompression Sickness?
When you breathe compressed air underwater, your body absorbs nitrogen. The deeper and longer you dive, the more nitrogen your tissues absorb. If you ascend too rapidly, that nitrogen doesn't have time to safely dissolve and is instead released as bubbles. These bubbles can cause joint pain, dizziness, paralysis, or even death if not treated quickly.
Even recreational dives within no-decompression limits can lead to DCS if a diver skips safety stops, has poor hydration, is cold, or exerts themselves too much after a dive.
Key Symptoms to Watch For
Symptoms of DCS can range from mild to severe. Some of the most common include:
Fatigue or weakness
Joint and muscle pain (especially in the arms or legs)
Dizziness or difficulty walking
Tingling or numbness
Chest pain or shortness of breath
Skin rashes or mottling
Symptoms may appear immediately after surfacing or up to 24 hours later. If you or your dive buddy experience any of these, seek medical help immediately.
Preventing Decompression Sickness
The good news? DCS is largely preventable. Here’s how:
Dive conservatively: Stay within no-decompression limits and use dive computers wisely.
Ascend slowly: Always ascend at a rate of no more than 30 feet per minute.
Make safety stops: A 3–5 minute stop at 15 feet is a must on any dive over 30 feet deep.
Stay hydrated: Dehydration increases the risk of DCS.
Avoid alcohol before/after diving: It can thin the blood and promote bubble formation.
Rest post-dive: Don’t overexert yourself right after surfacing.
If you plan to do multiple dives or dive daily over the course of a trip, consider using Enriched Air Nitrox to reduce nitrogen buildup. Be sure you're certified and know how to manage its limits.
When to Seek Help
If DCS is suspected, administer 100% oxygen if available, keep the diver lying down, and call emergency services or a local hyperbaric facility. Even mild symptoms shouldn't be ignored. Early treatment in a hyperbaric chamber can greatly improve recovery.
For added peace of mind, dive insurance providers like DAN (Divers Alert Network) can cover treatment and evacuation in the event of an emergency.
Happy and safe diving,
The ScubaBlast Team
NOAA. (n.d.). Decompression Sickness (The Bends). Retrieved July 2025, from https://oceanservice.noaa.gov/facts/bends.html
Divers Alert Network. (n.d.). Decompression Sickness Overview. Retrieved July 2025, from https://dan.org/health-medicine/health-resources/diseases-conditions/decompression-sickness/
PADI. (n.d.). Understanding Decompression Illness. Retrieved July 2025, from https://www.padi.com/articles/understanding-decompression-illness