Emergency Evacuation and Lifts in a Building

by Vanessa Griffin Vista Access Architects

Vanessa has over 20 years experience in the construction industry, working in a variety of roles, from the certification of buildings, to the undertaking fire safety upgrades to existing buildings and more recently as an ACAA Accredited Access Consultant. Vanessa has a passion and drive for access, not only as an Access Consultant but also in the role of Vice President on the Board of NADO (Nepean Area Disability Organisation), and the Disability Access Committee for the Blue Mountains City Council.

As the National Construction Code evolves every three years with a new update, there seems to be one taboo subject that appears to never make the update to be mandated in the design of buildings. Building design standards are transformed to ensure inclusive design so that persons can enter the building, however, the NCC/BCA is almost silent on how mobility impaired, the elderly, or hospital patients may be evacuated other than with the provision of fire isolated stairs, in which many are unable to use.

A lift provides all occupants the opportunity to move safely and freely around buildings and the built environment. It is very common to find signage near a lift call button “Do not use the lift in the event of a fire” and this has been industry practice for a reason:

• You may not know the location of the fire within the building. The lift may very well open onto a storey within the building impacted by fire.

• The lift may have a function known as ‘Go to ground’ which is a shutdown mode where the doors open and the ‘calls’ are disabled in which an occupant would not be able to call/ request for the lift from their location during an emergency.

• The fire brigade and emergency services often use the lifts to move around and gain fast access to the building leaving the stairs for the evacuation of people who are able to negotiate the stairway. The use of the lift by occupants would slow this process for the fire brigade and emergency services.

• Lifts have the ability to spread smoke between storeys as they travel up and down the lift shaft within the building which can cause additional issues to occupants.

Whilst this all seems logical, where lifts are not designed for this purpose, it leaves those unable to evacuate via stairs at a higher risk.

In the aftermath of the collapse of the World Trade Centre Towers in New York 2001, a shifted focus was towards lifts and their use during evacuation in the event of an emergency. Designers, engineers and researchers have been asking whether the availability of lifts during emergency egress are appropriate in circumstances to improve egress from tall buildings. Research has concluded that potential difficulties impacting the evacuation of taller buildings includes obstructions (such as hydrant risers and fire hose reels), mobility impairment, illness, fatigue, counter flow (people and rescuers going the other way) and footwear that is not suited by the occupants to walking down many flights of consecutive stairs (sorry Louboutin).

A lift in a building provides the freedom for an occupant or visitor to move freely within the building. This is not just restricted to people with a disability but also other members of the public including parents with prams.

As building designs and materials are evolving to incorporate a more inclusive design as well as major steps in technology; one major critical aspect is that we mandate access to and within a building, however, the biggest danger is that the building standards for Australia are all but silent on the issue of evacuation. The BCA does however provide a Performance Requirement in the BCA/NCC relating to the use of lifts in an evacuation:

Figure 1: Performance requirement DP7 Evacuation Lift from the NCC 2019

Whilst the Performance Requirements provide measures to be considered, the BCA/NCC as a document it is silent in providing a Deemed to Satisfy (DtS) clause for the provision of lifts to be utilised in evacuation, which is very unusual as the other performance requirements generally relate to at least one clause where applicable for the DtS.

In more recent times there have been discussions around the design of creating a safe refuge in buildings for people with disabilities. Particularly as we are mandating access into a building via building standards, however, the big issue for evacuation in the event of an emergency has been a tabled item each new version of the BCA/NCC.

A safe refuge creates other issues such as maintaining clear paths for the more agile person to continue safe evacuation. A person who relies on a device for mobility would more than likely require more than one person to provide assistance to safely evacuate. Additionally, what if there were multiple wheelchair users on a floor, a safe refuge may only provide for one wheelchair, so a choice has to be made.

Figure 2: Example of a safe refuge design for a wheelchair user in a fire isolated stair.

The additional cost to buildings to increase the floor area within a fire isolated stair would be seen by many as a waste of floor area, given the additional area would reduce the available net floor space for which a profit could be achieved for the build. Additionally, it is within the corner of the fire isolated stair to the landing that a fire hydrant riser would be designed to be located, which would require an additional increase to the floor area to accommodate the safe refuge. The cost in design and construction of the refuge area has been seen as a waste as it is based on the ‘what if?’ and therefore placing a cost to a person's life.

It is common that we at one point in time have all waited for some period within a lift lobby, and this would be no different in an emergency situation. There would be three steps to consider for evacuation via a lift:

1. Safety - waiting for the lift

2. Safety - when using the lift

3. Safety - when exiting out of the lift to evacuate the building

And the issue is that safety cannot be a defined term. All three of these elements combined provide a bigger design challenge not only for use and operation, but also the final point of evacuation.

The idea would be to provide a refuge lobby to each level. This would be a significant added expense to the developer which in no doubt would be passed onto the consumer with a significant profit margin. Not to mention the additional annual cost to the owner of the building to have this element checked and certified on an annual basis.

The lift lobby as a minimum would require fire resisting bounding construction which would provide a protected waiting area for the occupant, and the pressurisation of the lobby to mitigate smoke ingress and the spread of fire within the bounding construction of the lobby. Additionally, a separate electrical circuit from the building to ensure independent operation of the lift would be required.

Figure 3: Example of a protected lift landing (Copyright of the ABCB Handbook: Lifts Used During Evacuation 2013)

The BCA already addresses the construction of fire resisting lift shaft and doors in the DtS of the BCA, however, smoke separation has not been included. Smoke is a critical element as it can spread to the lift car and compromise the user, and it may spread to the lift shaft and travel into other non-fire/emergency impacted floors. It may not be known that in the event of a fire a person is more likely to die from smoke inhalation and breathing complications, than physical burns to the body from the fire.

The air movement created by the lift car moving between floors is critical and must be managed similar to that of stair pressurisation.

A user of a lift in an emergency would need to discharge safely from the lift and the building. It would be ideal for the lift in the fire mode response to travel directly to the ground floor or the level with the most direct step free access to open space outside of the building. The discharge point of the lift is critical as this area must be protected, more so because lift doors operate automatically once the required floor for discharge has been reached.

The operation and use of the lift is the biggest obstacle. In the fire mode operation, it would be key to evacuate the floor in emergency first, then return to the floors above the emergency to safely evacuate other persons with the lift, bypassing the danger floor so that it did not stop and open the doors to the hazard. We must also consider the impact of water for a person to safely evacuate should the building be sprinklered as this could have additional impact to a mobility device and the slip resistance of the floor surface.

Lifts suitable for emergency egress use are available on the market within Australia, however the pressurisation of the lift lobby has not been mandated, therefore not enforcing evacuation via a lift to be considered and mandated.

Additional safety measures for consideration for a lift suitable for emergency egress include the provision of back up power, fire warden training which varies from building to building, signage, CCTV, the provision to allow emergency phone calls, a visual storey number as well as voice activation. The lift needs to provide adequate information to provide a person with a disability the confidence to operate and use the lift in an emergency.

In the modern world it seems that we as a society value inclusion and ensuring a person with a disability is afforded to the same equitable facilities as those abled bodied. We can only hope that the Australian government recognises the need to provide safe evacuation for person with a disability and lead the world with legislation into the future.