The new National High level isolation Unit at the Mater Misericordiae University Hospital in Dublin is a specialist isolation facility dedicated for the management of patients diagnosed with High Consequence Infectious Diseases (HCIDs). It is engineered with stringent infection prevention and control systems, including negative pressure environments, anterooms for staff decontamination, HEPA filtration, specialized waste management protocols, and robust communication systems to care for single patients or small cohorts during high-risk outbreaks.
From the outset, MMUH set an uncompromising vision: to deliver a world-class, first-in-class facility. To achieve this, the project team undertook extensive research, including site visits to established Isolation Units across the UK and Europe. These visits provided first-hand insight into operational workflows, infection prevention protocols, and design considerations, many of which were adapted and incorporated into the MMUH facility concept.
The HCIU was strategically located within the STW Designed Rock Wing, a newly completed section of the hospital that had been purposefully reserved for this development. While integrated into the hospital’s infrastructure, the unit was designed to function as much as possible as a standalone facility — a “hospital within a hospital.” This concept ensured that all required services and support systems were contained within the unit footprint, including a dedicated plantroom located adjacent to the clinical areas but within the containment boundary. This self-sufficiency minimises reliance on external systems, reduces contamination risks, and enhances resilience during high-risk operations.
Client and End User Engagement Process
Scott Tallon Walker Architects initiated a 1:1 scale mock up of the design to test the functionality of the space, the personnel and material flows and to ensure all staff understood the exact nature of the layout. Using the latest projection technology and making use of the detailed BIM Model, we were able to project a life size plan of the facility onto the floor. This allowed users the opportunity to walk through the spaces and make adjustments as required.
The design process was underpinned by an extensive and highly collaborative engagement period between client, designers & contractor, during which a critical equilibrium was achieved between clinical effectiveness, operational efficiency, design quality and uncompromising safety.
Every aspect of the facility’s function, workflow, and performance was rigorously assessed and co-developed in partnership with the dedicated MMUH team led by Dr. Deirdre Brady, Consultant Microbiologist to the Mater Misericordiae University Hospital . This integrated approach resulted in a state-of-the-art High Level Isolation Unit that exceeds international best practice in the containment and management of High Consequence Infectious Diseases (HCIDs).
"This Unit will play a critical role in protecting the public from outbreaks of unexpected infectious disease threats in the future, should we need it. Remarkably designed, cutting edge facility...."
Former Minister for Finance, Paschal Donohoe
Architecture
The MMUH HCIU was required to achieve stringent performance parameters in order to function as a certified high-containment suite. These requirements included robust containment integrity, ease of decontamination, and compliance with international biosafety and infection control standards. Traditionally, containment facilities are designed with a strong emphasis on functionality, often prioritizing “function over form.” Such spaces typically feature sealed internal walls with visible, surface-mounted services, resulting in a utilitarian appearance that is effective for laboratories but less suitable for patient care.
Given the HLIU’s purpose as a clinical treatment environment, the design brief diverged from this conventional model. The Hospital required a facility that would not only meet rigorous containment standards but also provide a therapeutic, patient-centred environment. Therefore, the interior finishes were specified to the highest standard possible for a healthcare containment setting, balancing clinical functionality, infection control, and patient well-being.
Impact for End Users
Both the patient care areas and the laboratory were required to achieve containment standards equivalent to Biosafety Level 3+ (BSL-3+). However, the design team faced the additional challenge of creating an environment that was not only functionally secure but also supportive and therapeutic. Traditional biosafety laboratories often adopt an industrial aesthetic, but MMUH sought to balance stringent biocontainment measures with patient- and staff-centred design principles. The result was a facility that combines advanced technical safety with a clinical environment conducive to high-quality care and staff well-being.
Access Control and Security
Access to each controlled area is strictly restricted to trained and authorized personnel. Entry is managed via electronic card-swipe systems, integrated with MMUH’s site security protocols, ensuring compliance with internal governance requirements for high-risk facilities. Only staff with appropriate biosafety training and clearance can enter the containment suites, reflecting best practice in laboratory biosafety and healthcare infection control.
Engineering and Sustainability
The HLIU’s biosafety strategy relied heavily on its dedicated and independent HVAC systems, each designed in compliance with ASHRAE guidelines, CDC BSL-3 requirements, and WHO recommendations for airborne infection isolation facilities.
Each of the three containment zones—Patient Suite A, Patient Suite B, and the BSL-3+ Laboratory—was provided with an entirely separate HVAC system to eliminate any possibility of cross-contamination. These systems operated as single-pass configurations with 100% fresh air supply and no recirculation. Supply air was pre-filtered centrally, with H14 terminal HEPA filters (in accordance with EN 1822) installed within the patient treatment rooms to ensure the highest air purity at the point of delivery.
The HLIU is located in the recently completed Rock Wing Hospital, designed by Scott Tallon Walker Architects which meets Nearly Zero Energy Building (NZEB) requirements and aligns with the 'National Climate Change Policy,' and DCC's Sustainable Energy Action Plan.
