PADI Nitrox Course


Dive for longer and be back in the water sooner with enriched air, also known as Nitrox. This popular PADI specialty course will teach you how to use Nitrox safely and enjoy its many benefits.

You can complete your PADI Enriched Air (Nitrox) course on board our Cairns-based overnight vessel OceanQuest.

What is Nitrox?

Nitrox is a mixed gas of Oxygen Enriched Air between 23% oxygen and 40% oxygen. The air we breathe is approximately 20% oxygen and 80% nitrogen.

During diving, water pressure causes the nitrogen we breathe to be absorbed into the bloodstream. The higher the pressure, the more nitrogen is absorbed, and the greater the risk of decompression illness. The higher the oxygen percentage in your air tanks, the less nitrogen we absorb, leading to a longer no-decompression limit and a longer dive time.

Advantages of Nitrox

  • Longer no stop times: extend your bottom time and increase your safety margin
  • Reduced post-diving fatigue: as your body has less residual nitrogen to get rid of after your dives, research shows divers report feeling less tired after diving on Nitrox, compared with diving on air.

PADI Nitrox Course options

There are two sections to this course. You’ll complete the academic portion on board OceanQuest with an instructor. This includes video presentation, knowledge reviews and an exam.

The practical portion involves two open water dives using Nitrox. You’ll learn how to manage your oxygen exposure, set your dive computer for Nitrox diving and analyse the gas contents of your tank.

Choose your preferred course option below. The price shown below is the Nitrox course cost only – you can choose your length of stay (from 1 to 6 nights) on board OceanQuest after clicking the booking link.


Overnight Trip

Course Outline:

Academic portion and two practical dives completed on board


  • All required PADI materials
  • All dive and snorkel equipment, and full tuition
  • Fresh chilled water, tea and coffee
  • Two outer reef locations per day
  • Transfers from Cairns city accommodation

Book now

PADI Nitrox Practical Portion

Overnight trips on OceanQuest
Nitrox Course
Nitrox fills per tank

Includes all equipment and tuition. Prices valid from 1st April 2019 to 31st March 2020. Cairns Taxes/Levies: $20 per person per day (subject to change without notice). Fee includes: EMC $6.50. Fuel, Port, and Administration Charges $13.50. Port Douglas Tax/Levies: $6.50 EMC only.

Additional info

Prerequisites and forms



  • Nitrox fills ($10 per tank)
  • Snacks and beverages
  • Photo purchases
  • Digital camera hire
  • Quality souvenirs
  • Cairns northern beaches transfers $20pp

What to bring

  • Hat, sunglasses and sunscreen
  • Swimsuit and towel
  • Cert card and logbook
  • Overnight bag with changes of clothing, including warm clothing and socks for overnight wear
  • Toiletries
  • Reef and Port Authority charges ($20 per person per day)

Bedding and bath towels are supplied on board. Excess baggage can be stored at our Draper Street office at check in.

Medical and altitude information

All scuba participants must meet medical questionnaire requirements. Some conditions or medications may prevent you from diving.

Currently the rules state that for a single no decompression dive, you should not fly/go to altitude for at least 12 hours, or 18 hours after multiple dives. Divers Den recommends waiting a minimum 24 hours whenever possible. These are guidelines only, there is no guarantee that these recommendations will prevent decompression sickness. There are no current guidelines regarding diving after flying.

Altitude is defined as 300m/1000ft above sea level. Certain other tourist attractions around Cairns and Tropical North Queensland involve travelling to altitude. These include the Atherton Tablelands and the Skyrail Rainforest Cableway, so we recommend a gap between booking these experiences and any dive course or trip. Under normal circumstances, you should be out of the water on your last dive by 12pm (midday) on our overnight trips and 2pm on our day trips.