Foam is an important element to look for when selecting assembly line seating. However, the type of foam used in the construction of a chair is something that’s often overlooked. Foam is produced with varying characteristics and quality.

Robust chair construction contributes to long-lasting support and adjustability. For example, chairs made with 10 and 12 gauge steel will be able to withstand more heavy-duty use and abuse than products made with fiberglass or plastic.

Foam is another important element to look for when selecting assembly line seating. However, the type of foam used in the construction of a chair is something that’s often overlooked.

Foam is produced with varying characteristics and quality. Some types of foam will break down over time and lose its ability to adequately support a person. Better quality foams will continue to spring back and provide consistent support over time, even when the chair is used by a variety of people, molding itself to each individual’s particular contours.

Design, and the quality of components, materials and construction techniques used in assembly line seating, varies. For example, one leading chair manufacturer uses a self-skinning foam that is contoured to fit the buttocks, the back and neck.

Another company combines a core of high-grade upholstery foam and a tough, thin, pliable, molded polyurethane skin. A beaded texture combined with the polyurethane’s elasticity provides sensory stimulation to end users to combat fatigue and discomfort.

Many industrial seat manufacturers traditionally use polyurethane foam, because it is soft and durable. But, use of new types of biofoam may eventually trickel dow to workstation seating applications.

Recently, some Tier One automotive suppliers, such as Johnson Controls and Lear Corp., started to use a biofoam that is not based on petroleum products. They claim that new seat cushions made from plant-derived materials, such as soybeans, can be more readily recycled than traditional polyurethane.

However, according to Liz White, editor of Urethanes Technology International, a trade magazine based in London, “there is a lot of misleading stuff out there, and [automotive] seat makers are not averse to making us think they're using lots of natural products. The level used is currently very low.”

Polyurethane foam is made from two components: isocyanates and polyols. “Some, but by no means all (at least at present) of the polyol used for flexible foam for seating can be replaced by natural oil polyols,” White points out. “The industry has used many of these for a long time.

“But, the isocyanate content cannot be replaced by natural materials,” adds White. “Hence ‘biofoam' is basically a foam with well under 50 percent (often 5 percent to 10 percent) bio-content. It is still a polyurethane foam, and is recyclable or not in exactly the same way as a standard polyurethane foam.”