How to improve fire safety in 2020

External wall compliance

Several major high-rise fires around the world in recent years have deepened our understanding of how fire spreads both outside and inside buildings with modern façades.

This prompted New Zealand's Ministry of Business, Innovation and Employment (MBIE) to review the methods currently used to demonstrate that external wall cladding systems meet the Building Code's fire safety objectives. In particular, it examined how New Zealand standards should be interpreted and whether alternative international fire-resistance testing and assessment methods are suitable for use here.

Early in 2019, MBIE released its guidance on the fire performance of external wall systems. The document takes a more innovative and detailed approach to linking external wall fire analysis with building height, setting out low, medium and high risk categories.

Each category sets corresponding requirements for the insulation, framing systems, façade materials and other components of the buildings concerned.

The guidance began influencing newly designed projects in 2019, and is expected to be applied more comprehensively in 2020.

{ad}

Construction safety

The fire at the SkyCity International Convention Centre caused substantial financial losses and left thick black smoke hanging over Auckland for days, drawing further attention from industry stakeholders and the public to construction site safety.

Fire and Emergency New Zealand (FENZ) announced that it had begun reviewing its handling of the fire in response to public questions about how it started, how it got out of control and why it took so long to extinguish.

In guidance published in November 2019, the Building Research Association of New Zealand (BRANZ) noted that investigating the cause of the SkyCity convention centre fire would take time. The blaze demonstrated the need for particular care when undertaking any activity on a construction site that could cause a fire.

The relevant safety requirements are expected to be enforced more strictly in 2020.

For example, NZS 4781:1973, the code of practice for safety in welding and cutting, provides guidance for hot work outside workshops, including gas cutting, torch welding and the use of naked flames.

The standard explicitly requires a hot work permit to be obtained before undertaking such work, as do many insurers.

Fire risks in Airbnb accommodation

New Zealand has many Airbnb-style accommodation providers. The Government will strengthen its oversight of this accommodation in 2020, and this is expected to include fire safety requirements. By comparison, established lodges and hotels have fire-rated walls and doors separating rooms, along with compliant fire protection systems. When a fire occurs, these systems can promptly alert the fire service, while sprinklers installed in rooms and corridors can quickly control or even extinguish the fire, reducing losses.

Airbnb-style accommodation, however, presents certain fire safety risks.

• To increase profits, operators often rent individual rooms in a house to different short-term tenants or travellers. From the perspective of behaviour during fires, these guests often do not know one another. In an emergency, they may be so focused on escaping that they forget to promptly alert strangers in other rooms, or may not even know that other rooms are occupied.

• Rooms in such accommodation often lack fire separations, allowing smoke and fire to spread rapidly to other rooms.

• As these properties are usually ordinary homes converted to a different use, they often have only basic smoke alarms that are not connected to the fire service. If operators neglect fire safety, depleted batteries may prevent alarms from sounding, or alarms may be installed in unsuitable positions and fail to provide an effective warning.

• Basic smoke alarms cannot control or extinguish a fire, which can delay firefighting.

• Although some operators provide fire blankets and portable fire extinguishers, their use is not actually the approach recommended by the fire service. Research in New Zealand and overseas has found that people may underestimate the severity of a fire and delay escaping and raising the alarm while trying to fight it with these tools.

To improve fire safety in this accommodation, the Government may introduce some of the following requirements in 2020:

Properties would need to be retrofitted with compliant fire-rated walls and doors. This requirement is relatively unlikely, as whole-house alterations are expensive and many older homes are unsuitable for conversion.

• Properties could be rented only as entire houses, rather than by individual room. Marketing them as an 'entire house' would help ensure that guests know one another, making it easier for them to escape together in a fire. However, this would restrict the market, as most short-term guests need only a room.

• Properties would have to install alarm systems connected to the fire service. These systems cost several thousand New Zealand dollars to install and incur annual maintenance charges. False alarms, such as those triggered by guests cooking or smoking, could also result in a fine. Their advantage, however, is that major alterations to the house are unnecessary.

All these anticipated requirements could increase operators' costs, but they may well become necessary in the new year to reduce safety risks.

Working together

Drawing on many years of industry experience, fire engineering consultancy Origin Fire says fire safety engineers should understand both the theory and practice of fire safety engineering, have extensive experience in fire testing, and understand systems and measures relating to firefighting, passive fire protection, emergency lighting and exits.

They need a thorough understanding of fire safety standards and the Building Code, and must use evidence-based judgement to advise the building industry on all aspects of fire resistance and reaction to fire.

At the same time, construction businesses must recognise that fire safety is not solely the responsibility of fire safety engineers. It also involves the responsibilities and work of other design professionals, project managers, builders, contractors and subcontractors, right down to the actions of individual workers.

Successfully managing fire safety risks in 2020 will require more of those involved to share responsibilities, collaborate and work towards a common goal.

Planning fire safety early

Throughout 2019, it became increasingly clear that fire safety was no longer simply a slogan invoked when problems arose, but required more advance consideration and assessment.

Origin Fire has found that its clients usually begin considering fire safety during building planning and design, bringing fire engineering into projects much earlier than in previous years.

Traditionally, fire engineers became involved only after the design was completed, to demonstrate that it complied with fire safety requirements.

This left us little or no scope to improve a project's fire safety measures easily, so any necessary improvements often resulted in adverse effects such as project delays and increased costs.

Using our expertise earlier in a project to achieve fire compliance is undoubtedly a more sensible and effective approach.

Early involvement means we can add value by reducing overall construction costs without compromising safety.

We expect more 'wise' clients to begin working with Origin Fire early in their projects in 2020.

The many benefits of involving Origin Fire in early fire safety design include:

Optimising the building's position on the site to avoid unnecessary fire-rated external wall construction.

Optimising material costs, construction costs and construction time.

Discussing the internal building layout to avoid expensive passive fire protection costs.

Designing passive fire protection during the design phase to avoid costly rework caused by construction errors.

Ensuring essential fire protection elements are included in the base tender price to avoid expensive contract variations.

 

Alex Zhu

Dr Alex Zhu is a fire engineer and project development manager at one of New Zealand's leading building fire consultancy firms,

Origin Fire (www.originfire.co.nz). He has many years of experience in building fire engineering design, practice and management, and has contributed to fire engineering design and construction for numerous large buildings.

His doctoral research involved fluid dynamics, examining airflow dynamics and their relationship to fire safety design.

His research is directly applied to Origin's high-precision modern fire engineering design, using advanced virtual technology to build 3D fire simulations that show where fires occur and how quickly they travel through large buildings.

 

Michael James

At one of New Zealand's leading building fire consultancy firms,

Origin Fire (www.originfire.co.nz), the CEO and chief engineer has over 25 years of experience in building fire engineering design, management and practice, and has participated in and led fire engineering design and construction for numerous large buildings.

Michael has extensive experience, including dealing with city councils and fire service providers.

He brings distinctive solutions to fire safety challenges in apartment buildings, high-rises and large buildings.

Michael previously served as managing director of Pacific engineering consultancy;

he is currently the New Zealand president of the international Society of Fire Protection Engineers.