The correct hand position for giving chest compressions to an adult is to place the heel of one hand on the center of the person's chest, specifically on the lower half of the breastbone (sternum). Then, place the heel of your other hand directly on top of the first hand and either interlock your fingers or lift them off the chest to keep them from pressing down. Your shoulders should be positioned directly above your hands, with elbows locked and arms straight, so you use your upper body weight to press down vertically. The compressions should be done to a depth of about 5 to 6 cm (2 to 2.5 inches) at a rate of 100 to 120 compressions per minute. After each compression, allow the chest to fully recoil without lifting your hands completely off the chest to avoid losing contact.

Summary of Key Points:

• Heel of one hand on the center lower half of the breastbone.
• Other hand on top of the first, fingers interlaced or lifted off the chest.
• Shoulders directly over hands, arms straight with locked elbows.
• Compress to 5-6 cm depth.
• Compression rate: 100-120 per minute.
• Allow full chest recoil between compressions.

This positioning ensures effective chest compressions to circulate oxygenated blood during CPR in adults.