Smoke alarms: what, where and whose responsibility?
Australia has experienced several fatal fire incidents in recent years,
particularly in Queensland. In this context, the type, location and use of
smoke alarms were a key focus throughout this inquiry. The committee heard a
range of evidence about ionisation and photoelectric smoke alarms, including
the different types of fires they are intended to detect; the cost of different
types of smoke alarms; and where in residential properties smoke alarms ought
to be positioned.
This chapter considers some of these issues, particularly:
whether ionisation or photoelectric smoke alarms are most appropriate
for residential use;
where smoke alarms should be positioned in residential
properties, and whether smoke alarms should be mandatory in sleeping areas; and
who should have responsibility for ensuring smoke alarms are
installed in residential properties and whether the current regulatory scheme
needs to be amended.
Ionisation or photoelectric smoke alarms?
Both ionisation and photoelectric smoke alarms can be used in Australian
residential properties under the Building Code of Australia (BCA) and
Australian Standard (AS) 3786, except in the Northern Territory where only
photoelectric alarms are permissible.
Ionisation and photoelectric smoke alarms detect smoke in different
ways. Photoelectric alarms:
use a light beam aimed through the detection chamber but away
from a light sensor. When smoke enters the detection chamber it scatters the
light beam allowing some light to reflect onto the sensor which activates the
In contrast, ionisation alarms:
...use a small amount of radioactive material positioned
between two electrically charged plates. This ionises the air and allows a
current to pass through the air between the plates. When smoke enters the
detection chamber it reduces the current by disrupting the flow of ions between
the plates. The smoke alarm detects the drop in current and activates the
The most succinct description is that photoelectric smoke alarms 'see'
smoke while ionisation smoke alarms 'smell' smoke.
A number of submitters and witnesses discussed the relative merits of
both types of smoke alarm: a key point of contention was whether ionisation
smoke alarms are the most appropriate for use in a residential setting,
considering the most common house fire incidents.
Most fatal residential fires take place at night, primarily between 8.00 pm
and 8.00 am, and peaking between midnight and 4.00 am. There are two stages of
fire: smouldering and flaming. Smouldering fires 'represent a slow surface
reaction between a solid fuel and oxygen in the air resulting in inefficient
burning of the fuel', producing visible smoke of a large particle size. Flaming fires
result when heat transferred to the surface of a burning fuel forms combustible
gases which mix with oxygen in the air and burn in a hot luminous region
referred to as the flame, develop rapidly and produce fine particles of smoke; The Fire
Protection Association Australia (FPA) submitted that, '[g]iven the types of
materials used in furnishings and floor coverings etc. and the likely ignition
sources within a residential occupancy, the most likely fire type to be
encountered whilst occupants are asleep is a smouldering fire producing visible
Commissioner Mullins of the Australasian Fire and Emergency Service
Authorities Council (AFAC) stated that smouldering fires also present a
significant risk to sleeping occupants, because they produce toxic smoke which
inhibits a person's ability to wake up:
...A smouldering fire is more lethal than a flaming fire...A
flaming fire produces water vapour, a lot of carbon and soot and carbon
monoxide and carbon dioxide. Carbon monoxide is toxic. I will explain that in a
moment. Carbon dioxide can exclude oxygen and asphyxiate. It is about 10 parts
CO2 to one part carbon monoxide in a flaming fire, because there is plenty of
oxygen, so it combines to form CO2 instead of CO, so it is less toxic. But the
heat and the fire travel, making it untenable very quickly.
The smouldering fire produces about the same amounts of
carbon monoxide and carbon dioxide. If a person is asleep and they breathe in
carbon monoxide their sense of smell is dulled and they will not wake up to the
smell of smoke...Carbon monoxide has more of an affinity to red blood cells,
which transport oxygen around the body, than oxygen so it will push out the
oxygen and bond with the red blood cells. People will go into a deeper sleep
until they actually become unconscious and they will not wake up. They cannot
wake up. They are actually unconscious.
The amount of carbon monoxide in the bloodstream can lead to
the muscles that are looking for oxygen to operate the cells in the muscles.
The heart muscle will just give up, because there is not enough oxygen. It is
very insidious...You cannot just give [the person] oxygen. There are not enough
red blood cells available to take it on.
The FPA agreed that the level of fire safety risk is highest when
occupants are sleeping because 'human senses are dulled during sleep and
response time to any fire that is likely to start is increased'.
Several submitters made particular reference to the increased risk of
fire 'flashover' in modern homes. Fire flashover describes the situation in
which a room and its contents become so hot that it pyrolyses, meaning that
flammable vapours are given off.
These flammable vapours, known as hydrocarbons, then ignite. AFAC stated:
What we find these days is that typical furnishings...have
polyurethane foam...[which] burns at a far higher heat than wood, cotton or
anything else, so very high temperatures. So it heats up the room far more
quickly, and even the paints we have on our walls have plastics in them, so
they give off hydrocarbons. Our carpet is probably synthetic and gives off
hydrocarbons very quickly; the wool would not have. So there is much quicker
fire development...when it is in the smouldering phase is when you have to get
the warning, because you might have two to three minutes to get out of the
place. So you cannot have a smoke alarm and say, "When it's flaming, it'll
get me out." It is all too late. By then it is too late.
The Commonwealth Scientific and Industrial Research Organisation (CSIRO)
likewise stated that:
...much of the existing research is not reflective of the new
materials used in modern housing construction and furnishings. Similarly,
earlier research does not always reflect room configurations and open plan
living areas found in contemporary Australian homes. On this basis, CSIRO would
suggest Australia considers a review of existing research, addressing gaps in
understanding of modern materials and construction techniques. New research
should address detection technologies and the requirements for installation,
including the quantity and location through the building.
The majority of submitters advocated for the use of photoelectric alarms
over ionisation alarms in residential settings; for example, the MFB stated
that 'photoelectric alarms provide the best detection across a range of fire[s]'. The committee
heard that photoelectric alarms perform better where fires are smouldering, and are generally
less likely to produce false alarms, particularly in and around
kitchens and bathrooms.
Several witnesses called for a ban of ionisation smoke alarms. The Logan House Fire
Support Network (LHFSN) remarked:
Ionisation alarms are not smoke alarms; they are flame
detectors. Ban them and take them off the shelves. Mandate photoelectric smoke
alarms to be installed in every bedroom and every hallway.
The World Fire Safety Foundation (WFSF) was equally strident in its
For almost 15 years, The World Fire Safety Foundation has
warned that scientific evidence proves that ionisation smoke alarms are so
defective that they should immediately be banned and recalled.
Research we have just recently conducted in New South Wales
found that photoelectric alarms operated far more quickly than ionisation alarms
for smouldering fires—sometimes tens of minutes, sometimes half an hour,
sooner. In a flaming fire, ionisation alarms sometimes operated more quickly
than a photoelectric alarm but the difference was seconds. We very clearly
advocate only photoelectric alarms. My personal view is: ionisation alarms
should be banned.
People have said that one [alarm technology] is good for
flaming fires and one is good for smouldering. In my experience as a
firefighter just about every fire I have ever been to started as a smouldering
fire and went through a stage until it became a flaming fire. To say that they
are equal and good for different circumstances is to me a fallacy, an absolute
AFAC concluded that ionisation alarms are still being used in Australia
because they meet a 'flawed Australian standard testing regime'.
The FPA disagreed with this view, stating that 'ionisation alarms are
not defective and do not fail relevant Australian standards or international
It did, however, state that ionisation technology 'has a particular usage,
which in many cases in residential is inappropriate'.
It recommended that:
All residential buildings should be fitted with photoelectric
smoke alarms in the first instance in order to treat the highest fire safety
risk in residential buildings. Ionisation smoke alarms are effective in
detecting fast-flaming fires that contribute to some of the fire risk in
residential buildings, which would only be considered supplementary to
photoelectric smoke alarms.
Standards Australia (SA) stated that photoelectric smoke alarms are a
good minimum measure for use in residential properties because they respond to
a broad range of fires:
I think the general push has been that, as a minimum—if you
are going to put the very minimum that is required into your home—you should
really use photoelectric, because that will cover a broad spectrum of fires.
Very rarely in a house fire are we going to have a pure fuel. Very rarely in a
fire in a house, even if I am burning methylated spirits, will the only thing
that is going to burn be methylated spirits. Sooner or later, it will break out
onto the carpet or, if it was a kitchen fire, into the kitchen cabinets and so
on...sooner or later you are going to have secondary material, secondary fuel sources,
that will burn with a visible smoke. That is why the standards committee took
the position it did. Even in a fast-flaming fire scenario, the belief is that
photoelectric is not that far behind because you are never going to have a pure
But—on the question of banning ionisation—ionisation could
still be a useful tool as a device supplementary to that minimum requirement.
Banning them outright, in our opinion, is not necessarily the answer to the
problem. But picking the most appropriate technology, the most fit-for-purpose
technology, for the application is the issue.
The Australian Building Codes Board (ABCB) disagreed with this evidence.
It stated that 'there has been no independent peer reviewed, robust and verifiable
evidence provided to it that would support the calls to ban ionisation smoke
It also submitted that:
Another issue we need to consider is the number of fires that
are flaming and the number of fires that are smouldering. We do not have that
evidence either. We do not actually know. We understand that photoelectric
perform better with a smouldering fire. If you think about a hotel situation or
a hospital or other type of care facility, the type of fire that might initiate
in that type of environment probably would be a smouldering fire. But in your
own home, we know from other evidence, the majority of fires start in kitchens.
They are not, necessarily, going to be a smouldering fire
The CSIRO, which provides the only facility for testing smoke alarms for
Australian Standard accreditation, explained that it is difficult to compare
the operation of ionisation and photoelectric smoke alarms. While both alarms
must activate within a particular range of smoke obscuration (that is, how
dense the smoke is and how much it obscures the air), photoelectric smoke
detectors are measured using a photoelectric ruler, and ionisation alarms are
measured against a reference ionisation detector. Put simply:
It is the same test, just with a different requirement. We
compare photoelectrics to an optical measuring device. Ionisations are measured
to a reference ionisation measuring device. So we have two sets of reference
The CSIRO explained:
We do not report the results on time; they are reported on
the level of the measuring instruments at the point that the detector goes into
alarm. The time is irrelevant in that test criterion. What is reported is the
reference instruments' reading at the time of operation.
The CSIRO also emphasised that:
The new standard...actually requires photoelectrics to perform
to a flaming fire and ionisation to perform to a smouldering fire. I think it
is a much better test regime; however, the new standard was published in 2014.
It was adopted into the building code in May this year, and the building code
would be required for the manufacturing community, so manufacturers have two
years to retest all their current stock.
Cost of smoke alarms
The committee heard evidence about the cost of photoelectric smoke
alarms as opposed to ionisation alarms, and the impact this has on consumers' purchasing
decisions. Mr Naumovski informed the committee that while photoelectric alarms
have decreased in cost, ionisation alarms are still significantly cheaper. He argued,
however, that photoelectric alarms save money over time:
...you can purchase a nine-volt ionisation alarm for $10, but
you have to buy a nine-volt battery each year. So you have to pay about $6 or
$7 each year—and you have got to try and remember to replace it, or, if it
false alarms, you are going to disconnect it. At the end of the 10-year period,
that nine-volt alarm has cost you about $80 or $90. You can buy a photoelectric
10-year—the best technology out there right now—for $50. You
are actually saving money.
Mr Keith Golinski submitted that, when compared with the costs
associated with house fires, it could be of financial benefit to governments to
provide smoke alarms free of charge:
I believe that the photoelectrics cost $2.50 each to produce
whereas ionisations cost $1.25 each to produce. The medical costs, insurance
costs and human costs are astronomical now, so even providing a million smoke
alarms would be a saving. Handing out smoke alarms would be a great way to save
money. They are not an expensive item. It just seems so ridiculous that such an
inexpensive item is not provided.
In regards to regulating new housing construction, the Housing Industry
Association (HIA) indicated that it would not object to the additional cost of
photoelectric smoke alarms:
...on any cost differential between photoelectric and
ionisation we would happily concede that cost, given the issue we are talking
about here. Again, given that the provision now is for smoke detectors to be
hard-wired and also interconnected, the differences in the products themselves
I suspect would be relatively negligible in the price of the home, if it is
proven that that is what the ideal solution is.
Location of smoke alarms
The BCA mandates the installation of smoke alarms in certain locations
within a residential property, but not in bedrooms. Some states and territories
do currently require smoke alarms to be installed in bedrooms in buildings of a
particular classification, for example, existing Class 1b buildings in NSW, and Class 1b
'budget accommodation' over two storeys high in QLD.
The committee heard evidence suggesting that smoke alarms should be
required in each bedroom of residential dwellings. Professors Thomas and Bruck
conducted a study examining smoke alarms and the likelihood of them effectively
notifying sleeping occupants of a smoke source. The study concluded:
...the effective notification of occupants can only be achieved
with smoke alarms in every room. Without them in every room the sound level in
many locations is likely to be too low to achieve reliable notification,
particularly of sleeping people but even of many people who are awake. This is
generally the case with doors open but always the case with doors closed.
...in dwellings early detection of smoke can only be achieved
with smoke alarms in every room. The time to detection (given a particular
smoke source) is shown to be influenced by closed doors, the room in which the
fire occurs, the location (room or hallway) of the detector, the type of
detector and the smoke alarm manufacturer but the time to detection is
particularly influenced by the type and form of the material that is burning.
Early detection and notification therefore requires
interconnected smoke alarms in every room.
Commissioner Mullins of AFAC likewise stated that he had attended fires
where a person perished because the fire started in their own bedroom:
...earlier this year in Campbelltown in Sydney we had a
situation where a shiftworker was asleep in the morning and had the bedroom
door closed. A fire started in a wardrobe. There was no smoke alarm in the
bedroom. The fire got bigger. He slept through, and the smoke alarm in the
hallway did not operate, because the smoke never reached it. He perished in
that fire. We found that he had woken up, but it was too late.
The FPA recommended that the BCA be amended to require alarms to be installed
in sleeping areas,
or at least master bedrooms to improve occupant response to a fire.
The FPA stated that, assuming the household alarms are interconnected, this
would mean that 'the occupants of the master bedroom (in a family situation,
the parents) are effectively the fire warden, who could then assist others if
The ABCB agreed that installing more smoke alarms in homes, and
interconnecting them, could lead to a decrease in fire fatalities. However, in a
2012 Regulatory Impact Statement (RIS) the ABCB argued that this would not be
an appropriate level of minimum regulation. The Board stated that the
interconnection of smoke alarms in every room of every house 'may be
represented as best practice. As the National Construction Code (NCC) is a
minimum regulation document it may be of value to consider a range of options
between the status quo and [that option]'.
It stated that the ABCB:
...operates under an intergovernmental agreement...[and]must have
regard to a number of key objectives contained within the intergovernmental
agreement: establish codes and standards that are the minimum necessary to achieve
its mission...provide regulations that are proportional to the issue so that the
benefits to society are greater than the costs...ensure that the competitive
effects of regulation have been considered; and encourage a reduced reliance on
The ABCB also emphasised that changes to the NCC would not automatically
apply to existing building stock in all jurisdictions, and that, '[w]ithout
State and Territory adoption it is likely to contribute to approximately 1.9%
of the overall building stock'.
As discussed earlier in this chapter, many submitters and witnesses
advocated for ionisation smoke alarms to be banned in residential settings on
the basis of their perceived inferiority to photoelectric smoke alarms.
Early in the inquiry, the committee shared this view. However, as the
inquiry progressed, and the committee's understanding of the differences
between ionisation and photoelectric smoke alarms grew, it refined its thinking
on this matter.
The committee is convinced that multiple, interconnected smoke alarms
should be mandatory in all residential properties and agrees that photoelectric
smoke alarms should be used in preference to ionisation smoke alarms. However,
the committee does not agree that ionisation smoke alarms should be banned: photoelectric
and ionisation smoke alarms detect different fires in different ways and are
therefore fit for purpose in particular locations. The committee is also wary
about the implications of banning outright ionisation smoke alarms: the
committee believes it would be a grave error to potentially leave Australian
households with the impression that no smoke alarm is better than an ionisation
Across Australia, the committee believes that installation and
maintenance of smoke alarms must be improved. Approaches by Australian
governments to date have not succeeded, if some of the recent fire tragedies
are indicative, and something must be done to ensure that all Australian homes
are fitted with appropriate and working smoke alarms. It seems to the committee
that the lack of smoke alarms, either because they have never been installed or
because they are not operational, continues to be a significant concern with
respect to residential fires.
Before discussing in more detail possible changes, the committee
acknowledges the complexity of the current regulatory scheme. It could be said
that there are actually nine similar yet separate regulatory schemes: eight
operating in each state and territory, and one operating in relation to all
newly constructed dwellings subject to the operation of the NCC. Change will
not necessarily be easy, however, the committee believes that reform is
necessary and must be tackled.
Making any amendments to the scheme to give effect to the committee's
proposals (and applying them to every residential property in Australia,
regardless of a property's classification or age) will require the support and
participation of all states and territories: a number of organisations are
involved in developing and implementing smoke alarm regulatory measures, and each
state and territory has its own legislation dealing with smoke alarms. At
present, the NCC has been adopted by each state and territory, but the
agreement operates only in relation to new building stock. Many states and
territories have extended some of the regulations to existing building stock, but
the rules vary between building types, and between jurisdictions (see chapter
1). In this regard, the committee acknowledges comments by the ABCB that
amending the NCC will not mean that improvements automatically apply to
existing building stock, as well as its argument that some approach better than
the status quo but not as ambitious as best practice should be attempted. The
committee agrees with the first part of this statement but does not believe the
challenge is insurmountable; the committee rejects the second part: Australia
should undertake steps to achieve best practice for smoke alarms in residential
In the committee's opinion, the following steps should be taken:
the installation of interconnected, and preferably mains powered,
photoelectric smoke alarms supplemented where appropriate by ionisation smoke
alarms should be mandated for every residential property irrespective of
classification or age;
photoelectric and ionisation smoke alarms should be sited in
appropriate locations within every residential property; that is, ionisation
smoke alarms should be installed in locations where fast, hot fires are most
likely to occur while photoelectric smoke alarms should be installed in
locations where smouldering fires are most likely; and
the current regulatory scheme, with the agreement and input of
all Australian jurisdictions, must be amended to require the installation and
maintenance of smoke alarms as outlined above.
The committee therefore recommends that the NCC (incorporating the BCA)
is amended to require the installation of interconnected, and preferably mains
powered, photoelectric smoke alarms, supplemented where appropriate by
ionisation smoke alarms, in every residential property and specify the type of
smoke alarm that must be used at different locations within each residential
property, taking into account the different smoke detection properties of
photoelectric and ionisation smoke alarms. To give effect to this change, the
committee recommends that all state and territory governments adopt the amended
NCC and agree to apply it to all residential properties, both new and old, and irrespective
of the age of the property.
The committee recommends that the National Construction Code is amended
to require the installation of interconnected, and preferably mains powered,
photoelectric smoke alarms, supplemented where appropriate by ionisation smoke alarms,
in every residential property and specify the type of smoke alarm to be used at
different locations within each residential property, taking into account the
different smoke detection properties of photoelectric and ionisation smoke
The committee recommends, to give effect to Recommendation 3, that all state
and territory governments adopt the amended National Construction Code and agree
to apply it to all residential properties, irrespective of the age of a
In some jurisdictions, the point at which a property is sold, tenanted
or hired triggers the requirement that compliant smoke alarms be installed.
These are logical points at which a property's smoke alarms could be checked
for compliance, given that they already typically involve scrutiny of the
building's state of repair. Checking smoke alarms when properties are going to
be rented or hired would help to ensure that occupants who may be unfamiliar
with the property, or even with household fire safety, are living in a safe and
compliant dwelling. It would also benefit building owners by ensuring that
properties do not sit for extended periods of time with smoke alarms
potentially having been disconnected or not maintained.
The committee recommends that all states and territories implement
mandatory compliance checks of smoke alarms in residential properties whenever
a property is sold, tenanted or hired.
It is apparent that the inconsistency between jurisdictions and the lack
of clear and simple information about smoke alarms from a known, trusted and centralised
source means many people are currently unaware of their rights and
responsibilities with regards to home fire safety.
The committee received the coronial findings from a devastating
Victorian house fire which resulted in the deaths of three men in 2008, which the
committee regards as being particularly illustrative of this problem. This case
involved a property that had been rented for some time, between different real
estate agencies and without any direct landlord involvement, and where no
person could definitively state whether any smoke alarms had been installed in
the property and, if they had, whether or not the alarms had been maintained. Coroner White
stated that he was 'surprised by the lack of precise knowledge of the landlords
as to the state of repair of a device so fundamental to the future safety of
their tenants as a smoke detector'.
One of the surviving tenants stated that he had not even been sure of what a
smoke detector looked like until the police showed him pictures of them on the
Another tenant stated that they were not typically installed in his home
country, so he was not familiar with them, nor was he aware that they would
normally be fitted inside a house.
The Coroner commented that in Victoria:
There is no specific section or regulation that specifies who
is responsible for the maintenance and testing of smoke detector (sic) in a
rented residence. The answer lies in the convoluted interrelationship between
statute, common law and contractual principles.
He recommended that:
Victorian law be amended to ensure that all properties be fitted
with hard-wired smoke alarms which have a 10 year tamper-proof battery as a
backup, on every floor of every residence, regardless of the residence's age;
Victorian law be amended to clarify who bears responsibility for
maintaining and testing smoke alarms;
information be disseminated to landlords, real estate agents and
property managers as to the installation and maintenance of smoke alarms.
These findings, and the other fatal fires discussed in this report,
demonstrate how serious the consequences can be when no person connected with a
dwelling knows whether smoke alarms have been installed in a property, or has
responsibility for maintaining them.
In addition to the proposal to amend the NCC, the committee believes it
is vital to educate the public about the differences between smoke alarm
technologies, the benefits associated with the installation of smoke alarms
with different smoke detection properties in different locations, and the
importance of regular smoke alarm testing and maintenance. The committee is
also of the view that it is preferable to improve rates of installation and
maintenance of smoke alarms in residential properties via public education as
opposed to enforcement, which is likely to be a time-consuming and costly
undertaking for state and territory governments.
The committee recommends that Australian governments develop and
implement, in consultation with fire and emergency services, a package of
measures to educate Australians about the importance of smoke alarms and the
rules applying to smoke alarms in residential properties in each jurisdiction. The
package should be promoted widely and include a website with clear information
available in a variety of languages as well as resources to be used by
stakeholders such as real estate agents, community organisations and fire and
emergency services when engaging with members of the public.
The committee recommends that the Commonwealth, state and territory
governments develop and implement a package of measures, including but not
limited to a website and resources for key stakeholders, to educate Australians
different types of smoke alarms;
the benefits associated with installing smoke alarms with
different smoke detection properties in particular locations within a property;
the smoke alarm requirements that apply to residential properties
in each jurisdiction;
the importance of regular smoke alarm testing and maintenance;
who has responsibility for installing and maintaining smoke
alarms, and advice about how to do this or seek assistance to do so; and
the triggers for compliance checking of smoke alarms (for example
at time of sale, tenancy or hire).
In the event that Australian governments are not amenable to amending
the NCC, an alternative could be for Australian governments to subsidise (or
fund completely) the installation of smoke alarms in residential dwellings
across Australia, with a particular focus on vulnerable populations, and
including advice with regards to smoke alarm placement. A nation-wide smoke
alarm installation scheme would be a significant undertaking. It would require
careful planning, consultation with fire authorities and experts, and the cooperation
of the Commonwealth, state and territory governments in order to succeed. It
would also be prudent to consult with public and community housing providers,
and the real estate agency industry, in terms of rolling out the scheme in
Ideally, such a scheme would ensure occupants have early warning of
smoke, giving them more time to escape and contact emergency services, and
thereby reducing the risk of injury and death, as well as damage to their home
and other possessions. It would also be of significant value to the community
as a whole. As the committee heard, it is the most vulnerable members of the
community who are currently dying in house fires, a worrying trend that needs
to be addressed.
In the event Australian governments are unwilling to amend the National
Construction Code and apply it to all building stock irrespective of
classification and age, the committee recommends that they consider
implementing a nation-wide smoke alarm household installation scheme that
includes consultation with:
fire and emergency services, housing providers and the real
estate agency industry; and
individuals and organisations working with vulnerable members
of the community.
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