The £150 million HMP Oakwood in Staffordshire is using advanced smoke and natural ventilation solutions from SE Controls to not only improve safety in the event of a fire, but also save energy at the prison, which has achieved a BREEAM excellent rating.
Located on a 50 acre site adjacent to the existing Featherstone Prison near Wolverhampton, HMP Oakwood was designed by architects Pick Everard and comprises of 17 buildings including a healthcare unit, first night unit and training centre alongside three ‘star’ shaped secure accommodation blocks, each providing 480 places.
Designed and developed by WSP Group with additional specialised input from SE Controls, the combined smoke and natural ventilation system was tailored to meet the specific criteria and configurations of the individual buildings to ensure they not only complied with the relevant natural ventilation standards, but also met strict smoke ventilation performance specifications.
In addition, all of the components, systems and solutions provided by SE Controls were fully CE certified and complied with the relevant European standards including EN12101 and BS9999.
The complexity of the smoke and natural ventilation system varied depending on the size and nature of the seven individual buildings, ranging from a relatively straightforward installation within the healthcare block, to the complex multi-zoned solution used in the each of the main accommodation blocks, which would need to allow the safe evacuation of more than 500 people in the event of a fire.
Each four-storey accommodation block is designed with five ‘arms’ radiating from a centre access core, with four of the five providing accommodation and the last one dedicated to housing services to the building.
In natural ventilation mode, AOVs and roof actuators open to allow stale hot air to escape, with fresh air being drawn in through automatic glazed vents at the gable end of each prisoner wing, which operate as two separate zones serving the lower two and upper two floors. Air intake is also provided through additional glazed vents in the curtain wall screens on the centre core between the wings.
When smoke ventilation is required, the system provides both natural and mechanical smoke ventilation to ensure the smoke can be vented quickly and effectively to keep corridors and communal areas clear to aid evacuation. In the event of a fire, natural smoke ventilation is provided by the core’s glazed vents with the addition of ducted dampers, while mechanical smoke extraction is handled by high level louvres together with duty and standby fan sets located at the end of each accommodation wing.
To enable the natural and smoke ventilation systems to monitor the air quality and operate effectively, SE Controls supplied and installed a 32 zone BMS and fire alarm interface panel for each accommodation block together with all necessary actuators, vents and over-ride switches as well as smoke extract fan starter systems and pressure monitoring.
SE Controls’ Commercial Director, Martin Oates, explained: “We have undertaken a number of smoke and natural ventilation projects within the prison sector and they each have their own specific demands. The distinctive design of the accommodation blocks at HMP Oakwood not only provide a secure custodial solution, but also enabled us to create a highly effective natural ventilation systems that improves safety and evacuation in the event of a fire.”