What should the surface be like when performing CPR?

When performing CPR, the surface should be firm and flat to ensure proper chest compressions can be delivered effectively. A firm surface allows for adequate recoil of the chest after each compression, which is essential for maintaining blood circulation. If the surface is too soft or cushioned, it can reduce the effectiveness of the compressions, as the chest may not be able to compress fully and recoil appropriately, which could hinder the return of blood to the heart. A flat surface also provides stability, allowing the rescuer to maintain the correct hand positioning and body alignment necessary for high-quality CPR. Therefore, the best practice is to ensure that the person receiving CPR is on a firm, flat surface to maximize the likelihood of a successful outcome.