A new isolation room design was built, commissioned and validated by BSRIA on behalf of the Department of Health, resulting in minimising the risk of infection transmission due to possible low airtightness levels between adjacent spaces.
The design was independently validated: a Positively Pressurised Ventilated Lobby (PPVL) room offers protection from an infectious patient and to an immuno compromised patient, by maintaining the access lobby at positive pressure from the patient’s room and the rest of the hospital, but also by maintaining the room at a neutral pressure.
BSRIA also quantified the protection the room offers to visitors and staff who are inside the room; the ventilation strategy dilutes the contaminant concentration inside the room, as well as providing a well-mixed space with no areas of higher contaminant concentration.
This novel design challenged the traditional design approach to isolation rooms – positive isolation rooms for immuno compromised patients and negative isolation rooms for infectious patients.
Blanca Beato Arribas, BSRIA Asset Performance Team Leader, said:
“A full size physical model including ventilation systems, pressure stabilisers, hospital furniture and heat loads was built and commissioned in BSRIA’s laboratories. Multiple test methods were used to investigate and challenge the design, including anemometry testing, air tightness, commissioning of specialist ventilation devices (pressure stabilisers), heat load tests, gas tracer tests and smoke tests.
“The mock-up enabled the measurement of the ventilation patterns inside the room, the airborne infection risks within and outside the room and the thermal comfort of the occupants in the room. BSRIA also carried out the study of ‘what if’ failure scenarios, namely the assessment of the infection risk in the event of fan failure or doors that were left open.
“The facility’s design consisted of a PPVL, a neutral pressure patient’s room and a negatively pressurised en suite. The room was intended to be used to accommodate either infectious or immuno compromised patients, therefore, acting as a typical negative pressure isolation room or positive one, respectively.”