To determine if your wheel chocks are suitable for heavy machinery, consider these essential factors: chock material, size, and load capacity. Opt for high-quality, durable materials like rubber or polyurethane that resist wear and tear. Ensure the chocks are large enough to match the tyre diameter and width of your machinery. Check the chocks' load capacity, which should be able to support at least 25% of the vehicle's gross weight. Additionally, follow industry guidelines and Australian standards to guarantee your wheel chocks provide optimal safety and stability for heavy machinery.