Parts that are identifiable as solely or principally used with operating tables, hospital beds, or dental chairs are generally classified within this heading rather than as generic parts. However, parts that are common to multiple product categories — standard fasteners, generic motors, or commodity upholstery — may be classified under their own material or component headings. A principal-use determination, supported by technical documentation, is the standard approach when classification is ambiguous.

When a dental chair is sold as an integrated unit with a built-in delivery system (handpiece connections, air/water syringe, suction, and cuspidor), the classification turns on which component imparts the essential character. US Customs and Border Protection has generally classified such integrated assemblies as dental chairs (furniture) when the seating and patient-positioning function is primary, but importers should obtain a binding ruling for high-value shipments to avoid reclassification risk.