Why are sand fill buckets kept at petrol pump?

Sand fill buckets are kept at petrol pumps as a safety measure to contain and extinguish small fires that may occur due to flammable materials. In the event of a fire, sand can smother flames by cutting off the oxygen supply, preventing the fire from spreading. This is crucial in a fuel-rich environment where the risk of fire is heightened. Additionally, sand is easily accessible and can be quickly deployed in emergencies.