In the precast concrete industry, quality manuals and plant certification programs help develop production of quality products and recognize firms that can fabricate products that meet quality control standards. In Reference 3 ACI Committee 121 defines Quality Control (QC) as "those actions related to the physical characteristics of the materials, processes, and services which provide a means to measure and control the characteristics to predetermined quantitative criteria. QC is a production tool." Quality Assurance (QA) is a management tool. Standards are important to quality control of precast concrete. Relevant standards are developed by industry and trade associations, such as the ACI, AWS, CRSI, PCI and NPCA. Another organization, ASTM, is a not-for-profit organization that provides a framework for development of standards for materials, products, systems, and services. ASTM standards reflect a consensus among producers, users, and others with general interests. Testing and inspection are the everyday basics of quality control. They don't add quality to a product. They evaluate a product against established standards and provide the opportunity to correct nonconforming work, and to adjust materials or production before nonconforming products are fabricated. Some of the man factors in quality control include: completeness of work orders and product drawings; quality of raw materials; quality of forms; placement of reinforcement; tensioning and transfer of prestress; concrete quality; placement and consolidation; product dimensions; positioning of embedded items; plant conditions; curing; and handling, storage, and transportation of products.