Nye og mer fleksible kontorlokaler krever nye tanker rundt brannsikkerhet
De siste tiårene har det skjedd en stor utvikling i hvordan kontorlokaler og arbeidsplasser er utformet. En stadig ny utvikling og modernisering, både av mennesker og teknologi, viser at nye krav og behov trenger nye løsninger. De tradisjonelle kontorlokalenes tid ebber stadig ut. Nå er videokonferanserom, meditasjonsrom, stillerom og sosiale rom ingen ukjente begreper lenger. Når måten man bruker kontorlokalene på endres, bør også måten man tenker på brannsikkerhet, endre seg.
Disclaimer: While realizing that a post Covid-19 world will most definitely bring its specific set of challenges and changes, this article will assume that previous work trends will constitute the new normal.
The past couple of decades have brought together major change in the way workspaces are designed, further straying away from the traditional offices and cubicles type of workplace. With the rising need for variable tasks within different types of projects, the requirements for more flexible arrangements in both furniture and spaces has also increased. We have recently witnessed bigger needs for focus spaces, individual and group video conferences rooms, as well as open plan layouts with hot desking.
Collaboration spaces are starting to replace traditional meeting rooms with their range of sizes and arrangements. Moreover, well-being spaces are now created to accommodate for non-work-related activities such as relaxations, meditation and exercise, and general socializing among colleagues.
The flexibility of modern spaces is what poses the main challenge.
When designing such spaces from a fire safety perspective, occupant loads are what usually determine the fire strategy in terms of the number and width of exit routes, along with the provision of other active and passive fire safety measures. In a traditional office setup, it is much easier to calculate those occupant loads with the certainty that fixed spaces provide. However, the flexibility of modern spaces is what poses the main challenge.
Assigning assembly factors and occupant loads to focus rooms, conference rooms, well-being spaces, among others is quite a difficult task. If we are to consider the usage of all these spaces, including the actual “offices”, and calculate our load based on maximum occupancy, the result will be occupant loads that are too conservative to the level that they become irrational. This is particularly an issue in buildings that were refurbished or converted into office buildings from a different previous use. The result can reach triple, and sometimes even more, the number of supposed occupants, hence affecting everything from exit routes to ventilation shafts and other active and passive fire safety measures.
Moreover, flexibility for future use will also be affected. A current client might be able to adapt to the fire safety measures imposed by the current occupant load, but the subsequent occupant might want different usage of the space which will result in the need for larger egress routes, increased ventilation capacity, or others. The cost and time constraints of amending those issues might be beyond acceptable.
Gaps in Legislation Standards
With the above being said, there seems to be a gap with how the building codes and standards address office spaces and what the newest trends are pointing at. Modern workspaces are becoming more and more utilized in ways that the codes are not able to address. For example, BS9999, most commonly used guidance in the United Kingdom, as well as NFPA 101 align a maximum occupancy density with a minimum exit stair width. However, they do not specify occupancy types that are needed in modern spaces, such as well-being spaces or specific breakout rooms. This leaves the fire engineer with the need for a performance-based engineering approach. The best practice in that case is considering certain additional fire safety provisions including sprinklers or increased fire detection in certain areas where they’re not explicitly required.
Being able to meet up with the requirements of creating an office space that is both functional and collaborative while also having dedicated workstations is a tricky issue. Achieving the occupancy limitations that fire safety compliance imposes resides in a successful fire engineering judgement. Such an approach can only be adopted if a fire safety management strategy is put in place, and actually applied regardless of any future changes.
A successful Fire Safety Management strategy (an example is those suggested in BS9997 - A guidance that propose fire risk management systems that can mitigate potential risks, most commonly used in the United Kingdom), can mitigate risk through continuously managed occupant loads. That can be done through a desk and room booking system which can pinpoint and control the occupant density and flow of a specific area at any given time.
This is a method that has been recently put into use for mitigating risks of Covid-19 exposure in offices but can also be employed for fire safety purposes. With such a practise put in place, building managers and fire engineers alike can justify not calculating the occupancy levels of both the desk spaces and the collaboration rooms simultaneously. This would form a performance- based approach to designing the egress routes while making sure that congestion would not occur in the case of a fire related event. As much as this is a reliable and justifiable approach, a large factor would be ensuring the full collaboration and commitment of the stakeholders involved.
Challenges will always be faced when trying to solve current problems with older written regulations. As office spaces will continue to evolve, codes need to follow suit at the same pace. As that might be an optimistic goal, the best coping mechanism is using the expertise and judgement of experienced fire engineers. Planning for future use, adhering to a strong Fire Safety Management system, and ensuring the correct performance-based approach is adopted and followed by all stakeholders can be the ultimate solution.
Some of the above can be referenced to the SFPE member forums and discussions.
Litt om journalisten:
Amani er en libanesisk arkitektingeniør med en spesiell interesse for fagfeltet sikkerhet. Hun har også en Mastergrad i brannsikkerhet fra Høgskulen på Vestlandet (HVL), som hun var ferdig med i 2020. Hun har siden begynnelsen av 2021 jobbet som Graduate Fire Engineer ved Arup UK, og skriver med brennende engasjement for Brennaktuelt.no, på fritiden.