Germs can spread from raw meat, poultry, seafood, or eggs to other foods. Keep them apart at every stage: shopping, storage, prep, and serving.

Tools move germs around a kitchen faster than anything else. Decide in advance which board belongs to raw food.

Source: USDA FSIS, Cutting Boards and Food Safety
The Simple Rule
Anything raw sits below anything that will be eaten without cooking. If a drip could land on it, move it up.