Microwave-safe Plastics
Many current plastic containers and food wraps are specially designed to withstand microwave radiation. Some products may use the term "microwave safe", may carry a microwave symbol (three lines of waves, one above the other) or simply provide instructions for proper microwave use. Any of these is an indication that a product is suitable for microwaving when used in accordance with the directions provided.
Read more about this topic: Microwave Oven