PE tarpaulins come in a variety of sizes to accommodate different needs and applications. The common sizes of PE tarpaulins can vary depending on the manufacturer and the specific requirements of the user. However, here are some general common sizes that you may come across:

1. Small: 6 ft x 8 ft (1.8 m x 2.4 m) or 8 ft x 10 ft (2.4 m x 3 m)

2. Medium: 10 ft x 12 ft (3 m x 3.6 m) or 12 ft x 16 ft (3.6 m x 4.8 m)

3. Large: 16 ft x 20 ft (4.8 m x 6 m) or 20 ft x 30 ft (6 m x 9.1 m)

4. Extra-Large: 30 ft x 40 ft (9.1 m x 12.2 m) or 40 ft x 60 ft (12.2 m x 18.3 m)

These are just a few examples, and there are many other sizes available in the market, including custom sizes that can be made to order. The choice of size depends on the specific purpose of the tarpaulin, such as covering equipment, protecting a surface, or creating a shelter.