Alternating Pressure Mattresses: A Home Guide

By Scott Smith. Last reviewed 21 October 2026.

How Does an Alternating Air Pressure Mattress Work?

The mattress or overlay is made of tubes or bubbles of air, connected to a quiet electric pump that hangs on the bed end. The pump fills alternate cells while others empty, then swaps them over in a regular cycle. This means no part of the body rests on the same point for too long. Most pumps have a comfort setting adjusted to the user’s weight, and an alarm if the power fails or the pressure drops.

Which Type Do You Need?

Higher-risk users are normally given a full replacement system through their community nursing team. The cheaper overlays sold online are mostly bubble or cell pads, which are designed for lower levels of risk.

Air Mattress for Bed Sores: What to Know

Pressure ulcers, also called bed sores or pressure sores, develop when skin and the tissue beneath stay under pressure for too long. A mattress is only one part of looking after the skin. Regular changes of position, good nutrition and hydration, keeping skin clean and dry and checking it daily all matter. If you notice red, purple or darkened patches that do not fade, or any broken skin, contact the GP or district nurse promptly. The NHS pressure ulcers page explains the signs and who is most at risk.

How to Set Up an Alternating Mattress

1. Place the overlay on top of a firm mattress, with the tubes connecting at the foot end.
2. Hang the pump on the bed end and connect the hoses without twisting them.
3. Switch on and let the mattress fully inflate before the user lies on it.
4. Set the comfort control to the user’s weight, following the instructions.
5. Cover with a single fitted sheet only; thick layers reduce the effect.

Check the pump is running and the cells are inflating every day. Feel under the user’s hips with a flat hand to check they are not bottoming out on the base mattress.

Dimensions, Weight Range and Bed Type

Overlays are made to fit a standard single bed in most cases, with a few made for larger or profiling beds. Measure the base mattress before buying and check the overlay will not overhang the edges. Each system lists a user weight range for the pump settings, so choose one that covers the person comfortably. On a profiling bed, make sure the hoses and power cable have enough slack to move when the bed raises or tilts, and that the overlay does not slide down when the head end is raised.

Cleaning and Infection Control

Wipe the overlay with a mild detergent solution and dry it well, following the maker’s instructions; harsh chemicals can damage the cells. Use a breathable waterproof sheet if there is a risk of spills or incontinence, but avoid plastic sheets that trap heat and moisture. Check the cells regularly for holes or splits, and the hose connectors for cracks. A slowly deflating cell usually means a puncture or a loose connection.

Are Alternating Mattresses Noisy?

Most modern pumps are quiet, but some people notice a gentle hum or the feeling of movement at first. Overlays raise the height of the bed, so check bed rails still reach high enough. The mattress surface can feel less stable for getting in and out, which matters for people who sit on the edge of the bed to stand. Keep the pump away from pets, and never use pins or sharp objects near the cells.

Can You Get a Mattress Through the NHS?

Yes, if you are assessed as at risk: the community nursing team or the hospital usually provides one, often on discharge. Ask the GP or district nurse for an assessment rather than buying straight away, especially if the person already has any skin damage. Buying privately can make sense for low-risk users or for a spare overlay.

Seat Cushions as Well

People who sit for long periods also need a suitable cushion, because sitting puts high pressure on a small area. Our alternating pressure cushion guide and the guide to wheelchair cushions for pressure care cover seating.

The overlays and pumps below were in stock when we checked each listing. Ask a nurse or occupational therapist which level of support is right before buying.

Frequently Asked Questions

How Long Should a Pressure Mattress Cycle Take?

It depends on the system. Follow the maker’s settings and the advice of the nurse who assessed the user.

Can I Use an Overlay on a Memory Foam Mattress?

Check the instructions. Most overlays work best on a firm base mattress.

What Happens in a Power Cut?

The cells slowly deflate. Many pumps sound an alarm, and some have a transport valve that holds air for a while.

Is a Bubble Mattress Enough?

For lower-risk users it may be. Higher-risk users need a system chosen after a professional assessment.