They can produced from either tubular or flat polypropylene (PP) woven fabrics. These fabrics can be both coated or uncoated and vary in different weights depending on the requirements of the Safe Working Load (SWL), or Safety Factor (SF). An FIBC can be as simple as an open top with a flat base used commonly within the building industry or, as a high tech unit produced within a clean room production environment to be used within the foodpharmaceutical industries.