What to Expect in Your First Hyperbaric Session

Short answer: A first session in a soft-shell chamber has four parts: preparing the room and equipment, getting in and closing the chamber, a gradual pressurization while you equalize your ears, and a gradual return to normal pressure. Sessions are often around an hour, but your prescriber and the manufacturer's manual set the exact procedure. Your physician should approve use before your first session.

Last reviewed: September 2026. Educational only, not medical advice. See our disclaimer. Follow your chamber's manual, which overrides anything here.

Before you begin

• Get medical clearance. Per the manufacturer, a prescription is required to purchase Summit to Sea chambers. Ask your physician about anything that could make pressure changes risky, such as ear, sinus or lung problems.
• Read the manual. Learn the controls, gauges, alarms and how to release pressure quickly.
• Set up in a clear, ventilated space. Keep the chamber and the oxygen generator away from flames, sparks and heat sources.
• Check the equipment. Inspect the zipper, seals, hoses, gauges and power connections. Make sure the oxygen generator (10 LPM at 20 PSI for Summit to Sea) is connected as the manual describes.
• Prepare yourself. Use the bathroom, wear loose comfortable clothing, and follow the manual's list of items that must stay out of the chamber. Do not bring anything with a flame, spark or heat source.
• Tell someone. Have another adult nearby for your first sessions.

Getting in

Enter through the zipper (or walk in, on upright models), lie or sit on the mattress or chair, and make yourself comfortable before you close up. Bright interiors, viewing windows and, on some models, Bluetooth speakers make longer sessions easier. Have anything you plan to use, such as a permitted book, within reach.

Pressurization

The chamber fills with pressurized air and rises slowly to its working pressure. Summit to Sea chambers hold 4.4 PSI (1.3 ATA); other soft-shell chambers we carry are rated up to about 1.5 ATA. As pressure builds you may feel fullness or a click in your ears, like a descending airplane or a dive into a deep pool.

• Equalize early and often. Swallow, yawn or gently move your jaw. A gentle Valsalva, holding your nose and blowing softly, helps some people. Never force it.
• Slow down if it hurts. Ear pain means pressure is rising faster than your ears are equalizing. Stop, or slow pressurization according to the manual.

During the session

Once at pressure, most people simply rest. Sessions are often around an hour, but follow your prescriber's instructions and the manual. Keep an eye on the pressure gauge, and make sure the power-monitoring alarm and compressors are working. If you feel unwell or anxious, use the release valves and end the session as the manual directs.

Coming back to normal pressure

Depressurization is gradual and is controlled by the chamber's valves. Your ears may pop again. Do not open the zipper until the chamber is fully at room pressure. Move slowly when you stand up.

Afterward

• Drink water and give yourself a moment before standing.
• Note any ear, sinus or breathing symptoms and tell your physician if they persist.
• Wipe down the interior according to the manual, and store equipment as directed.

Common first-session concerns

• Feeling enclosed. Windows, a well-lit interior and a fan of familiar sounds help. Tell your physician if you are claustrophobic.
• Ear discomfort. Usually eases with equalizing, but ongoing pain means stop.
• Getting too warm. Compressed air can warm the chamber. Follow the manual's ventilation guidance.

Read the Hyperbaric Chamber Guide, see every chamber we carry, or contact us with setup questions.