Fixed Pressure CPAP Machines

Is a Fixed Pressure Machine Right for You?

Fixed pressure CPAP is the original — and still widely used — gold-standard treatment for obstructive sleep apnea. It works by holding your airway open with a consistent stream of pressurised air at a level determined during a professional sleep study. There are no algorithms adjusting the pressure in the background, no variable settings to manage. It simply delivers your prescribed pressure, all night, every night.

This makes fixed pressure machines an excellent choice for people who know their pressure requirement, have a stable therapy need that doesn't fluctuate much with season or lifestyle, and prefer simplicity and predictability in their device. They tend to be quieter in operation than auto machines, are often more affordable, and are just as effective as APAP when the prescribed pressure is correct.

The main consideration is that a fixed pressure machine won't adapt if your pressure needs change over time — due to weight changes, shifting health conditions, or other factors. If that's a concern, or if you don't yet have a titrated pressure from a sleep study, an Auto Pressure (APAP) machine may be a better fit. For a detailed comparison of both types, our guide to choosing the right CPAP machine walks through the key differences.

Want a complete setup ready to go from day one? Our Fixed Pressure CPAP Packages bundle a machine with a compatible mask and accessories at better-than-separate pricing.

Frequently Asked Questions

Do I need a prescription to buy a fixed pressure CPAP machine in Australia?

A prescription is not required to purchase a fixed pressure CPAP machine in Australia — however, it is strongly recommended. A fixed pressure machine delivers one set pressure all night, so if that pressure isn't matched to your actual therapy requirements, the machine may be less effective or less comfortable. If you've had a sleep study and been given a specific pressure, you can upload your prescription through our website and we'll configure your machine to the correct setting before it ships.

What's the difference between a fixed pressure CPAP and an auto CPAP (APAP)?

A fixed pressure machine delivers one constant pressure throughout the night — set in advance and unchanged regardless of how your breathing varies. An APAP machine works within a prescribed pressure range and adjusts automatically in response to your breathing moment by moment. Fixed pressure is the right choice when you have a known, stable pressure requirement. APAP offers more flexibility and tends to suit people who are new to therapy, whose pressure needs vary, or who don't yet have a titrated prescription from a sleep study. Both are equally effective when properly matched to the user's needs.

What happens if my pressure needs change over time?

It's not uncommon for pressure requirements to shift — usually due to significant weight changes, changes in sleeping position habits, or evolving health conditions. If you're using a fixed pressure machine and start noticing symptoms returning (such as increased snoring, waking frequently, or daytime fatigue), it's worth checking in with your sleep specialist. A follow-up sleep study can determine whether your prescribed pressure needs adjusting. Some users in this situation choose to switch to an APAP machine, which automatically accommodates a range of pressure needs without requiring reconfiguration.