Abstract: A sterile room structure (1) has an air wall (3) suspended from a purlin (5). The air wall (3) and an outer wall (2) and fixed walls (8) comprise panels (10) of high density phenolic resin construction. The panels are machined along the side edges to provide recesses for interengagement. Support of the panels is by way of bridging members which connect to the rebates (11) at joints between them. Joints are completed by seals of adhesive bio-sealant material to achieve desired adhesion and mechanical flexibility. The combination of phenolic resin panels, aluminium supports and coving members, and seals provides a sealed structure which may be easily modified later.