TB 028 Installation Of Access Doors Into Hazardous Plastic Duct Systems

Access for inspection, servicing, and specialist cleaning is a critical consideration in hazardous plastic ductwork systems. TB 028 provides design guidance for the installation of access doors in hazardous plastic duct systems used for chemical, biological, and radioactive applications, where operational risk and maintenance requirements demand careful planning. The bulletin supports designers and specifiers in determining when access doors are necessary and how they should be incorporated into higher risk ductwork installations. It reinforces the requirements set out in DW/154 Specification for Plastic Ductwork, which states that access doors should be used for inspection and servicing only, with broader access requirements referenced in DW/144. TB 028 highlights the importance of obtaining specialist advice when considering periodic internal cleaning, maintenance, and access for specialist cleaning equipment. It also outlines practical considerations for access door provision, including minimising the number and size of doors, positioning them to reduce leakage risk, ensuring an effective seal, and maintaining appropriate safety information for anyone opening the system. Designed for designers, specifiers, and professionals involved in hazardous exhaust and specialist ductwork systems, TB/28 complements the wider BESA technical guidance library. Key Features: Design guidance for installing access doors in hazardous plastic duct systems Relevant to chemical, biological, and radioactive ductwork applications Supports compliance with DW/154 and references access requirements in DW/144 Highlights the need for specialist advice on cleaning and maintenance access Outlines practical design considerations to help reduce leakage and operational risk Published Date: 14/04/2026 Number Of Pages: 2 PDF Download