Car and Office Cushion: Thickness and Foam Density

In short: for the office people usually choose a cushion of moderate thickness and medium density so as not to upset desk and monitor settings. In a car a cushion changes seat height, visibility and the distance to the pedals and wheel, so a small thickness, a non-slip base and safety matter especially. Exact numbers depend on your height and seat.

Office: what matters

• Thickness. The cushion lifts you, changing elbow and eye position. Moderate values (a few centimetres) usually fit; after adding one check the desk and monitor, see how to sit on the cushion.
• Foam density. Too soft sags quickly, too firm can press. For the office medium firmness is usually chosen.
• Shape. Flat, with a tailbone cut-out or contoured, see tailbone or lumbar cushion.
• Cover. Removable, breathable.
• Non-slip base. So the cushion does not slide on the chair.

Car: what changes

A cushion raises the seat, and that affects:

• visibility (easier, or worse because of the distance to the roof);
• distance to the wheel and pedals;
• seat belt position;
• the driver's position relative to the airbag.

Car recommendations

1. Do not take a cushion that is too thick. The added height can reduce headroom and change the ergonomics.
2. The cushion must be secured. A non-slip base or straps so it does not shift while driving and braking.
3. Do not block adjustments of the seat, seat belt or safety devices.
4. Check that you reach the pedals and wheel without strain.
5. Do not use the cushion if it interferes with safe driving.
6. If in doubt, ask the car manufacturer or a service centre.

Foam density

On material and density: memory foam. For a car, shape-stable foam of medium density is better: it does not sag or change seating height during a trip.

How to choose for both cases

Care

Do not wash the foam, wash the cover following the label, keep away from direct sun and heat, see foam care. In a car in summer the cabin heats up: do not leave the cushion in the sun.

When to see a doctor

Back or tailbone pain lasting several weeks, numbness or weakness: see a doctor, see tailbone pain from sitting work.