BSI has just published new Code of Practice (COP) BS 9992 for fire safety management for rail infrastructure. As expected, it builds on and often refers to the guidance in BS 9999: 2017 (Fire safety in the design, management and use of buildings – Code of practice).
Like the separate COP for residential buildings (BS 9991: 2015), the diversity of railway-related structures and buildings presents a different set of challenges for fire safety management and warrants a separate COP.
New Challenges of Fire Safety in Railway Buildings
It is clear from reading BS 9992 that there is huge variation in the fire safety challenges with rail infrastructure. Buildings can vary from small, rural stations to big, city stations; stations above ground and sub-surface stations and tunnels (the standard even introduces a new definition of rail structure, the enclosed station).
There are many old buildings in the UK rail sector, often mixed with new constructions. And, while there aren’t the challenges of people living in these buildings that are addressed in BS 9991, the number of people in a station can quickly change from a relatively small number to thousands if several trains empty at once.
Product Innovation
As with the design and fire risk assessments of other complex structures, especially when upgrading fire safety in older buildings, one hits problems that aren’t always solvable using existing or mass-produced products. In these cases, an innovative design and manufacturing company will often be able to work with you to find a solution through the development of a new product.
This is how we at Ritherdon like to work with our customers, with continual investment in our technical team, with product development and testing capabilities. Having our own factory also makes prototyping and product modifications relatively straightforward and quick to do. This is how we developed our first FireSeal, fire rated access panels to reinstate the required fire resistance of meter box openings in compartment walls in residential blocks in Leeds.
Fire Safety Management During Construction
The BS 9992: 2020 code of practice has a section (Section 10) that specifically deals with fire safety on rail infrastructure construction sites and during redevelopment of existing sites. This is because these projects are often undertaken on a large scale and can last for long time. Even more importantly, construction sometimes happens whilst the trains are kept operating.
Construction and redevelopment work around rail structures often involves working close to railway operations and public access areas such as stations. BS 9992 makes the point that the construction works should not make the existing fire safety provisions (means of escape, emergency service access, etc) worse.
Even though these are only semi-permanent installations, the same things should be addressed, such as the use of the correct materials (following BS EN 13501-1: 2018), fire doors, smoke control, compartmentalization and the protection of escape routes. Although they were not fire-safety-related the Ritherdon Temporary Builders Supply kiosks were designed to provide a range of products of suitable quality and robustness to be used on a similar, semi-permanent basis on construction sites.
Fire Stopping Measures for Safety and also Business Continuity
This new COP doesn’t have some of the detail that specifies fire resistance values for various elements of structure, that BS 9999 and BS 9991 have.
For passive fire protection, which is our particular area of interest, the standard refers to BS 9999: 2017 where you will find information such as that on required minimum fire resistances in Tables 22 to 24.
In this section (11- Fire safety systems design), unlike the other codes of practice, there is a subsection on business continuity. This is because, as well as creating hazards to the occupants, a fire in a critical railway structure can potentially immobilise a large part of this national infrastructure for a long time.
On the subject of service continuity, but on a shorter timescale, subsection 34.3 recommends that signalling and electrical control centres may need to remain operational for some time during an emergency.
For this reason, they should be separated from the rest of the building by a >2h fire-resisting construction.
Door sets and shutters in walls should provide at least the same level of fire resistance (E categorisation only required, not insulation) as the element into which they are installed. The same principle was applied to our FireSeal units in the Leeds flats and in other buildings where they have since been used.
Avoiding Damage to Fire Stopping Structures
And a final example of passive fire protection in the new standard that relates to one of the FireSeal range is the subsection 44.3.3 (fire stopping and service penetration seals). It recommends that “There should be provision for suitable and sufficient methods of replacing or adding services without damaging their associated passive fire protection. Where it is foreseeable that reconfiguration of services will be a regular occurrence, then fire-resisting systems designed to accommodate those alterations should be installed…”. This was one of the key criteria when we designed the Riser FireSeal with Medway Council.
The Riser FireSeal provides a vertical barrier over service risers, from floor to ceiling, up through buildings. This makes it possible to route new services up through the riser without breaking the fire-stopping barrier (traditionally installed at floor to ceiling level).
Brief Review of BS 9992: 2020
Hopefully this brief review of BS 9992: 2020 has given an idea of the interesting and varied potential fire safety issues that can be encountered when designing new rail infrastructure or during risk assessments of existing structures. These can often be found in quite extreme situations such as tunnels and can be peculiar to the rail industry. However, if you can develop a relationship with a manufacturer who is prepared to invest in innovation and who you can trust to do the job properly, then it might be that you can solve some of this problems together through product development.
Get in touch with us if you think Ritherdon might be able to help.
