For HMP Stocken, Fireworks deployed a custom-designed water mist fire system in just two months. Fireworks now protects over 250 custodial facilities.

HMP Stocken is a Category C prison that was first opened in 1985. Following several expansions, with new accommodation, facilities and workshops, it has achieved recognition for the quality and safety of its environment. In 2019, HMP Stocken became the first prison facility in the UK to incorporate the latest Ministry of Justice fire safety standard, STD/M/SPEC 054, into its fire precaution systems.

The prison’s newest wing adds a further 206 beds to its capacity. Fireworks was chosen to custom-design and install a state-of-the-art fire suppression system, leveraging the latest innovations in high pressure water mist fire protection.

New STDM Specification

One of the most recent developments in high pressure water mist fire suppression for the custodial sector is the new National Offender Management Services STD/M/SPEC 054. This standard has been developed for automised water mist fire suppression systems for areas identified as being of particular fire hazard, such as laundries and storage rooms.

A custom-designed system with three water mist solutions

Fireworks’fire protection solution for HMP Stocken’s new wing included the custom design, installation, testing and commissioning of a high pressure water mist system. The design incorporates automised water mist in cells and in areas identified as ‘special hazard’, as well as manually-operated water mist hose reel cabinets. A central 200 litre pump unit, backed up by a second redundancy pump, powers a network of over 900 metres of stainless steel pipework, water mist hose reel cabinets and 160 water mist nozzles.

1- In-cell protection

Side-wall mounted nozzles are located in each cell of the new block. These open, anti-ligature nozzles have been tested and approved by the BRE and Ministry of Justice. The nozzles are activated by a fire detection system and local automatic valves, so manual intervention is not necessary. In the event of a fire within a protected cell, smoke is detected by the dedicated detection system. A start signal is then sent to open the relevant solenoid valve. Through the subsequent pressure loss, the pump detects water flow and begins to propel water through the distribution pipework. Water mist is then discharged into the affected area only. Custodial staff have the possibility to bypass the solenoid control valve for each cell manually, to stop or start water flowing to the nozzle, regardless of whether a signal has been raised by the fire alarm system.

2 -Protecting special fire hazard areas

For areas designated as special fire hazard, such as laundries, Fireworks installed closed nozzles that are activated via glass bulbs that rupture when heat reaches a pre-determined temperature. This causes a flow of water which is then detected by the control panel, which in turn triggers the high pressure pump unit into operation. Water mist is then emitted at all of the affected areas, identified through nozzles with ruptured bulbs.

3 -Water mist hose reel cabinets for manual firefighting

The third aspect of the system is a series of high pressure water mist hose reel cabinets, for manual firefighting. Each of the high security, lockable steel cabinets includes a 35 metre hose reel assembly, with a handheld lance fitted with a water mist nozzle. The cabinet can be installed on wall surfaces, or flush fitted into wall recesses. Each cabinet is connected to the centralised high pressure pump unit. Operation is simple and to operate the hose reel a custodial staff member opens the flow control valve located inside the cabinet and squeezes the trigger located on the lance.

Installation, testing and maintenance

Fireworks custom designed HMP Stocken’s fire suppression system. Once the design was approved, installation and testing were completed in less than two months. Each of the 160 nozzle locations was tested to a limit of 150% of the system’s operating pressure, for a total of 10 minutes and then at normal operating pressure for a further 110 minutes

The system includes a full control and monitoring solution and is incorporated into the building management system and fire alarm.

Fireworks specialises in high and low pressure water mist fire suppression systems and is the leading water mist fire suppression company for the UK custodial sector. Fireworks’ fire protection systems now protection over 150 prisons, custodial suites and detention centres.