Using lifts during a fire
AN EVACUATION DESIGN GUIDE
AN INTEGRAL GROUP ENGINEERING WHITE PAPER
Contact silvia.misuraca@integralgroup.com
Disclaimer: This document is based on the best knowledge available at the time of publication. However no responsibility of any kind for any injury, death, loss, damage or delay however caused resulting from the use of these recommendations can be accepted by Integral Group, its member companies, the authors or others involved in its publication. In adopting these recommendations for use each adopter by doing so agrees to accept full responsibility for any personal injury, death, loss, damage or delay arising out of or in connection with their use by or on behalf of such adopter irrespective of the cause or reason therefore and agrees to defend, indemnify and hold harmless Integral Group, its member companies, the authors and others involved in their publication from any and all liability arising out of or in connection with such use as aforesaid and irrespective of any negligence on the part of those indemnified. This publication is primarily intended to provide guidance to those responsible for the design, installation, commissioning, operation and maintenance of building services. It is not intended to be exhaustive or definitive and it will be necessary for users of the guidance given to exercise their own professional judgement when deciding whether to abide by or depart from it. Version 1: September 2020
Front Cover Image: Render, Aurora Apartments, Melbourne VIC Australia
Contents Overview
4
How do we design lifts to evacuate occupants safely?
6
Ensuring safety while waiting for a lift
8
Ensuring safety while using a lift
9
Ensuring safety once out of the lift
11
Conclusion
12
Overview The use of lifts in the event of fire is actively discouraged, for good reason. Can we design them to be safely used?
4
The completed Aurora building utilised lifts for the evacuation of the upper levels (Level 66-86) and incorporated several strategies described in this article to ensure the safe evacuation of the residents via the lifts. We have always been told, usually by a small sign next to the lift call button, to not use the lift in the event of a fire. Instead, building occupants are guided to evacuate via the stairways. Generally, lifts are not designed for evacuation in the event of a fire, and therefore, this is good advice, for a few reasons: •
We may not know where the fire is located, and the lift could open on to a storey involved in fire. This has unfortunately caused many fatalities in the past.
•
The lift may ‘go to ground’ or shutdown in firemode, meaning occupants will be unable to call the lift.
•
The Fire Brigade often use lifts to move around the building; the general public using the lifts may slow down their operation and limit their effectiveness in fighting the fire.
•
Lift use could spread smoke between storeys, as they travel up and down the building.
The reasons to not use a lift in the event of a fire are sensible, where lifts are not designed for this purpose. However, for those unable to evacuate via the stairways, using a lift in the event of a building fire might be practical or necessary. Around 80,000 people in Australia regularly use mobility aids, including walking sticks and wheelchairs. In hospitals and aged care, most patients or residents are unable to readily move downstairs without assistance. In these buildings, evacuating building occupants horizontally between areas separated by fireresisting construction is a viable solution, though it is not always an option. As our aged care buildings, residential buildings and hospitals get taller, we need to ensure that all occupants can evacuate out of the building safely.
5
Overview |
The Integral Group Fire Engineering team have recently completed the design and commissioning of Melbourne CBD’s tallest tower, the 86-storey Aurora Building, located at LaTrobe Street, Melbourne.
How do we design lifts to evacuate occupants safely? As building design standards are being transformed to incorporate accessibility design elements, one aspect of accessibility requirements has not been updated: evacuation in the event of an emergency. Our National Construction Code (NCC), the Building Code of Australia (BCA) is almost silent on how mobilityimpaired occupants, the elderly or hospital patients may be evacuated vertically, other than providing them with stairs, which many are unable to use. The Australian Building Codes Board (ABCB) has released a guidance document relating to the use of lifts for evacuation, and there is a relatively new Performance Requirement in the BCA relating to the use of lifts in an evacuation, though it provides no Deemed to Satisfy (DtS) clause to go with it. The Australian Network on Disability has guidance on the evacuation of mobility impaired occupants , but it is generally limited to ensuring that adequate space in fire-isolated stairways are provided and suggests occupants simply wait for emergency services workers to assist them to evacuate. Lifts assist all occupants, but particularly mobility impaired occupants, to move around buildings safely. It is therefore logical that we should seek to design them to also be able to assist mobility impaired occupants to evacuate as well. So, the question is, how do we design lifts to evacuate occupants safely? Fundamentally the key aspects that need to be considered are: •
Ensuring occupant safety while they wait for a lift.
•
Ensuring occupant safety while they evacuate via a lift.
•
Ensuring safety when occupants come out of the lift and evacuate the building
The following sections outline several key, high-level strategies that should be incorporated into the building
design to allow the safe use of lifts in the event of a fire.
6
How do we design lifts to evacuate occupants safely? |
Ensuring safety while waiting for a lift A safe refuge zone is critical to the design of lifts for
A fire mode lift response strategy needs to be
evacuation. In almost all buildings, there will be a
developed to ensure priority is given to the occupants
period of time where people need to wait for a lift.
at highest risk over those further away from the fire.
Each level should therefore have a ‘refuge lobby’,
In this way, the wait time at the fire storey and those
protected with fire and smoke resisting construction.
levels closest to the fire can be minimised.
Further to passive protection, the lobby should also be pressurised with air to prevent smoke ingress.
Fire resisting bounding construction of lift lobby [including self-closing fire doors].
Protected waiting areas for occupants using lifts for evacuation.
Lift lobby pressurisation to mitigate smoke spread.
Figure 1: Example Lift Lobby Floor Plan
8
The construction of fire resisting lift shafts and doors
The air movement created by the lifts moving
is already included in the BCA DtS requirements.
between floors must also be managed and can be
Smoke separation, however, is not.
designed in conjunction with the pressurised lift
Smoke spread is a concern for two reasons.
lobbies and stairway pressurisation (if required).
Firstly, smoke may spread into the lift car, thus
These measures allow the lift journey to be
compromising the safety of its occupants.
protected from fire and smoke. Additional measures
Secondly, smoke may spread into the lift shaft and thereafter into non-fire-affected storeys, often aided by the pumping action of the lift moving in the shaft. By providing positive pressurisation to the smokeproof lift lobbies, a smoke-proof barrier is created around the lift, mitigating the smoke spread into the lift shaft, lift car and between floors.
such as back-up power provisions, warden training, signage, CCTV, emergency call phones, storey number readouts and automated messaging are all prudent to provide occupants with enough information and confidence for them to evacuate using the lifts.
Ensuring safety while using a lift |
Ensuring safety while using a lift
Occupants need to discharge from the lift safely. The
From this discharge point, there should be a clear
lift should travel directly to Ground Level or the level
path out of the building, and ideally more than
with direct access to a road or open space.
one path for redundancy purposes.
Upon reaching this level, the occupants remain
This may be combined with various other measures,
vulnerable, as the lift doors will generally open
such as programming the lifts to find an alternative
automatically.
stopping point if smoke is detected in certain areas
The discharge point must be a protected area, without
(such as the discharge lobby).
significant fuel load, so that the likelihood of fire in this area is negligible.
Left Image: Aurora Apartments Lift Lobby
11
Ensuring safety once out of the lift |
Ensuring safety once out of the lift
Conclusion
Image: Aurora Apartments, Melbourne VIC Australia
Many design factors need consideration when designing lifts for evacuation, with each building generally requiring a bespoke design. From an architectural and building services perspective, many of the design elements noted previously have spatial requirements and need to be considered with respect to the whole building layout and design. Involving a Fire Safety Engineer, experienced in designing lifts for evacuation early in the design process is best practice to develop the most effective evacuation strategy. Similarly, seeking consultation with other key design engineers, such as a Mechanical and Vertical Transport Engineer will assist in developing a robust design strategy. When the building fire safety is considered from a holistic viewpoint, lifts for evacuation can readily form part of an overall evacuation strategy. The use of lifts can not only supplement stairways for evacuation but also allow for the rapid evacuation of all occupants, irrespective of their ability to traverse stairways.
References: [1] Australian Bureau of Statistics (ABS) 2016, 4430.0 Survey of Disability, Ageing and Carers 2015, [2] Lifts Used During Evacuation – Handbook, Non-Mandatory Document, Australian Building Codes Board, 2013 [3] “Evacuation Procedures”. And.Org.Au, 2020, https://www.and.org.au/pages/evacuation-procedures.html