Your first HBOT (Hyperbaric Oxygen Therapy) session at ReviveO2 in Littlehampton runs about 65 minutes from arrival to leaving: 60 minutes inside the chamber at 1.5 ATA, plus 3 to 5 minutes either side for the gradual pressure change. This guide covers what to wear, what happens step by step, and how you might feel after.

At a glance
  • Total visit time: about 65 minutes
  • Chamber time: 60 minutes at 1.5 ATA
  • Location: Office 46, Bizspace, Courtwick Lane, Littlehampton BN17 7TL
  • Parking: on-site at Bizspace, plus on-street nearby
  • Best for: relaxation, post-workout recovery support, building a wellness routine
  • Pause and check first if: you are unwell, have ear or sinus issues, or are unsure about a health condition
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Wellness note: HBOT at ReviveO2 is a supervised wellness session, not a medical treatment. Indications for medical hyperbaric oxygen therapy are defined by the Undersea and Hyperbaric Medical Society (UHMS), and ReviveO2 sessions at 1.5 ATA fall outside that medical scope. Sessions are not intended to diagnose, treat, cure, or prevent any disease. Check with your GP first if you have a health condition or are unsure.

Before your first HBOT session: how to prepare

Arrive 5 minutes early on your first visit so you do not feel rushed. Your safety screening form is sent to you by email before your visit, so everything is checked in advance, not when you walk through the door. When you come in, we'll show you the space and walk you through what the session feels like.

Rescheduling is the right call if you have a cold, blocked sinuses, ear pain, or a chesty infection on the day. The reason is comfort: the small channel connecting your ear to the back of your throat, called the Eustachian tube, needs to open freely for pressure equalising to feel easy, and congestion blocks that.

Check with your GP first if you are unsure about a health condition or medication. Tell us in advance and we can guide you on whether you need clearance before you come in.

What to wear to an HBOT session

What to wear

  • Loose cotton clothing: comfortable and breathable
  • No synthetic fabrics: polyester, nylon, and spandex create static risk in oxygen-rich environments
  • No metal jewellery or watches: remove before entering
  • Remove shoes: you will be lying or reclining

What to bring

  • Book or magazine: we provide these too
  • Water bottle: we provide water, you are welcome to bring your own
  • Calm mindset: arrive settled rather than rushing
  • Any questions: we walk through everything before you start

What happens during an HBOT session at ReviveO2

An HBOT session at ReviveO2 has four phases: arrival and check-in, gradual pressurisation, the 60-minute steady phase at 1.5 ATA, and the gradual return to normal pressure. Tap each phase below to see exactly what happens, what you'll feel, and how long it takes.

Interactive: tap a phase to see what happens
1
Arrival
2
Pressurising
3
Session
4
Coming down
Arrival and check-in
First 5 to 10 minutes
You arrive, we show you the space and walk you through what the session feels like. Everything is explained before you get in. No rushing.
Tap "Next phase" to see what happens when the chamber pressurises

Click through each phase to see what happens and what to expect. Phase 4 links directly to booking.

How you might feel after your first HBOT session

Three responses are common after a first session: a calm, relaxed feeling; a clearer-headed alertness; or no noticeable change at all. All three are normal first-session experiences.

One session shows you what 1.5 ATA feels like inside the chamber. The cumulative oxygen exposure builds across multiple sessions, which is why most clients book a 4-session or 8-session package after their first visit, especially when the goal is general wellbeing support and recovery.

Most clients go straight back to their day. Drink water afterwards and take a moment before heading out. Sit for a minute and take your time if you feel a little light-headed.

Why your session works: what 1.5 ATA does inside your blood

Drag the pressure slider below to see how oxygen behaves at different pressures, from sea-level air to wellness HBOT and beyond. The right panel shows what happens to your blood and tissue at each level.

1.5 ATA Wellness HBOT
At 1.5 ATA on 100% oxygen, plasma-dissolved oxygen rises to about 4.5 ml per 100ml of blood, roughly 15x the level on normal air. Tissue cells now receive oxygen the red blood cells cannot reach.
4.5 ml/100ml
Dissolved O2 in plasma
15x
More than normal air
Extended
Tissue oxygen reach
Without HBOT, 1.0 ATA
With HBOT at 1.5 ATA
Red blood cell (carries O2)
Dissolved O2 free in plasma
Blood plasma (liquid)
Tissue cell (outside vessel)

According to Henry's Law (Henry, 1803), gas dissolves into liquid in direct proportion to the partial pressure applied. During your 60-minute session at 1.5 ATA breathing 100% oxygen, plasma-dissolved oxygen rises from roughly 0.3 ml per 100ml of blood at normal sea-level air to approximately 4.5 ml per 100ml: a 15-fold increase in oxygen carried by the plasma alone, reaching tissue red blood cells cannot access under normal pressure.

Who should not do HBOT: contraindications to check first

HBOT is not suitable for every person. Pause and check first if you are unsure. Do not attend if you have symptoms requiring urgent medical care or a suspected collapsed lung (pneumothorax), which is the absolute contraindication for any hyperbaric session.

Check with your GP before booking if any of the following apply to you, including but not limited to: pregnancy, uncontrolled medical conditions, recent ear or lung surgery, or current concerns about a medication. Every client completes a safety screening form sent by email before their first visit, so any questions are caught before you arrive. Read the full HBOT contraindications guide.

How to find ReviveO2 Littlehampton and parking

ReviveO2 is at Office 46, Bizspace, Courtwick Lane, Littlehampton BN17 7TL. We serve clients from West Sussex towns including Littlehampton, Worthing, Rustington, East Preston, Arundel, Bognor Regis, and Chichester.

On-site parking is available at Bizspace, with on-street parking on Courtwick Lane nearby. The closest bus routes stop on Courtwick Lane if you are travelling by public transport.

Ready for your first session? Book online with safety screening sent by email before you arrive. No referral needed.

Book your first HBOT session

Frequently asked questions

Most clients feel fine once they see the space and start. The chamber has viewing windows and we stay nearby throughout. Mention it before you begin if you are worried. Everything is explained and the pace is guided by you. Read the full claustrophobia guide.
Yes. Matt supervises from start to finish and you can communicate with him throughout the session. You are never alone or unsure.
Tell us straight away. We slow down or pause. Comfort comes first. Stopping and rescheduling is fine if equalising is not happening comfortably. Nobody will rush you. Read the full ear equalising guide.
Rescheduling is the right call. Congestion makes the Eustachian tube harder to open during equalising, which makes the session uncomfortable. Rebook when you are clear.
Plan for about 65 minutes total: 60 minutes in the chamber at 1.5 ATA, plus 3 to 5 minutes for the gradual pressure change at the start and end. Arrive 5 minutes early on your first visit.
Most clients go straight back to their day. We recommend drinking water and taking a moment before leaving. Sit for a minute if you feel light-headed.
Wear loose cotton clothing. Avoid synthetic fabrics including polyester, nylon, and spandex due to static risk in an oxygen-rich environment. Remove all metal jewellery and watches before entering the chamber.
Yes. ReviveO2 offers four other services: NSR (Nervous System Reset), Cellular Recovery (Red Light Therapy plus PEMF, Pulsed Electromagnetic Field), and Pelvic Floor Chair sessions. Many clients combine HBOT with one or more. We can talk you through what makes sense for your goals.
HBOT complete wellness guide (pillar) → What 1.5 ATA means in plain English → Ear equalising tips for HBOT beginners → HBOT and claustrophobia: how the chamber feels → HBOT contraindications: when to pause and check → How many HBOT sessions clients usually book →

Questions before booking? See package pricing on the memberships page, or book your intro session online.

Book a session

References

  1. Henry, W. (1803). Experiments on the quantity of gases absorbed by water, at different temperatures, and under different pressures. Philosophical Transactions of the Royal Society of London, 93, 29-274.
  2. Undersea and Hyperbaric Medical Society. Indications for hyperbaric oxygen therapy. uhms.org
  3. NHS. Hyperbaric oxygen treatment. nhs.uk
  4. Mayo Clinic. Hyperbaric oxygen therapy. mayoclinic.org
  5. DDRC Healthcare. Diving Diseases Research Centre, Plymouth. ddrc.org
This article is for informational purposes only and does not constitute medical advice. Wellness HBOT at ReviveO2 is not intended to diagnose, treat, cure, or prevent any disease. Consult your GP before booking if you have a health condition.
M
Matt
Founder, ReviveO2 Littlehampton

Matt is the founder of ReviveO2, a wellness centre in Littlehampton, West Sussex. He guides first-time visitors through the full check-in and session flow, with a focus on clear explanation, comfort, and safety screening. Matt completed hyperbaric chamber operator training in 2025 with DDRC Healthcare (Diving Diseases Research Centre), Plymouth, UK, including the Chamber Operator course, focused on safe chamber operations and session procedures.