Access doors are a vital part of any HVAC and ductwork system, providing safe and practical access for inspection, maintenance, and servicing of in-line equipment. Properly installed access panels allow engineers to carry out essential checks, cleaning, and repairs without compromising the integrity of the ductwork or the fire safety of the building. Without suitable access, routine maintenance can be difficult, time-consuming, or even unsafe.
Compliance with UK legislation and standards ensures that access panels are correctly sized, positioned, and fire-rated. Professional installation guarantees that panels provide sufficient accessibility while maintaining fire resistance equivalent to the surrounding structure. By installing compliant access doors, building owners and managers can safeguard equipment performance, ensure safety, and meet regulatory obligations.
Contact Marlowe Environmental Services today to arrange professional access door installation and ensure your systems are safe, compliant, and easy to maintain.
There are specific standards that govern the installation of access doors. BESA DW144 – Sheet Metal Ductwork specifies that an access panel must be provided adjacent to in-line equipment requiring regular servicing or intermittent access. Openings should typically allow hand and/or arm access, with the system designer specifying panel size and location where larger openings are necessary.
It is standard practice to install access panels for the inspection and servicing of plant and equipment, as summarised below under the responsibility of the ductwork contractor.
BS EN 9999 further specifies that access panels must provide at least the same level of fire resistance as the element into which they are installed.
| In-line equipment | Location | Party responsible for provision of suitable access panel | |
|---|---|---|---|
| Ductwork contractor | Specialist cleaning contractor | ||
| Control dampers | Both sides | Up-stream panel | Down-stream panel |
| Fire dampers | Both sides | To suit damper maintenance | Opposite side |
| Heating / cooling / re-claim coils | Both sides | Panels on both sides | — |
| Attenuators (rectangular) | Both sides | Up-stream panel | Down-stream panel |
| Attenuators (circular) | Both sides | Up-stream panel | Down-stream panel |
| Filter sections | Both sides | Up-stream panel | Down-stream panel |
| Air turning vanes | Both sides | Up-stream panel | Down-stream panel |
| Changes of direction | Both sides | — | One panel to suit |
| In-duct fans / devices | Both sides | Up-stream panel | Down-stream panel |
| Inlet / exhaust louvres | Both sides | One panel to suit | — |
| Intermediate cleaning panels | — | To suit frequency per TR/19 & DW/172 | |
Standard DW144 Spiral Access Panel
Designed for installation in circular or spiral ductwork systems, these panels provide compliant access for inspection, testing and maintenance.
Standard DW144 Rectangular Access Panel
Suitable for rectangular duct systems, these panels ensure safe and practical access to in-line equipment and internal ductwork sections.
DW144 Access Door with Saddle
Engineered for improved sealing and structural integrity, saddle-mounted access doors provide secure installation on various duct profiles.
DW144 Access Door with Intumescent Coating (Post-Certification)
These fire-rated access doors include intumescent coatings and post-installation certification, ensuring compliance with fire resistance requirements in accordance with relevant standards.
At Marlowe Environmental Services, we not only install compliant access doors into ductwork systems, but also provide a full range of fire damper services to ensure safety and legislative compliance.
Fire Damper Installation & Replacement
Fire dampers vary in type and configuration, from small perforation units to dampers located externally to fire compartments. Correct installation is critical to maintaining compartmentation and passive fire protection.
Fire Damper Testing
Fire dampers must be tested at least every 12 months by law (or more frequently depending on system type and building use). Regular testing ensures operational integrity and occupant safety.
Fusible Link Sourcing & Replacement
Fusible links come in various sizes and temperature ratings and are essential to the correct activation of fire dampers. Proper sourcing and replacement ensure the effective performance of the HVAC system.
Fire Stopping
Fire stopping systems must be inspected and any defects rectified to maintain fire compartmentation and building safety. Ensuring integrity protects occupants and supports compliance with fire safety legislation.
Ensure your ductwork systems are compliant, accessible and fire-safe.
Speak to Marlowe Environmental Services today to arrange a site survey, access door installation, or fire damper inspection and testing programme.
DW144 is a specification published by BESA that sets out standards for sheet metal ductwork construction, including requirements for access panels to facilitate inspection, cleaning and maintenance.
Access doors allow safe inspection, maintenance, cleaning and testing of in-line equipment such as fire dampers, attenuators and coils. Without compliant access, systems cannot be properly maintained or certified.
Fire-rated access doors are required where ductwork passes through fire-rated elements or where fire resistance must be maintained. The panel must provide equivalent fire resistance to the surrounding construction.
Fire dampers must be tested at least annually, in accordance with UK legislation and industry guidance. Some environments (such as healthcare) may require more frequent inspections.
Typically, the ductwork contractor is responsible for installing access panels during construction. However, specialist contractors may install additional panels to meet cleaning or compliance requirements.
TR/19 and DW/172 provide guidance on ventilation hygiene and access panel frequency to ensure ductwork systems can be cleaned and maintained effectively.
