Plastics burn don't they?

Has much changed since this was written in 2004???????????

An overview by John Rakic, Principal at J-RAK Consulting

(Prepared on behalf of the Alliance for Fire & Smoke Containment &

FPA Australia in 2004)

Research testing at facilities like FM Global Research facilities in the USA allow us to

understand the performance of building construction utilising plastic materials

Introduction

This article follows on from an earlier article I wrote early last year that featured in the

May 2003 issue of Fire Australia, (Fire rated insulated sandwich panels). Judging from

the number of calls I keep getting and the questions I have been asked from end users,

facility managers, consultants, risk assessors and manufacturers, there is still quite a bit of

confusion as to what is it that you need to do differently in today’s market to get

insurance for facilities incorporating plastics (Expanded Polystyrene in particular), why

do you need to do something different than what has otherwise been acceptable in the

past, and how much will it cost to upgrade if you do not want to use alternative materials.

The recent National seminar series held in most State Capitals of Australia, and in

Wellington New Zealand, organised by FPA Australia; “Plastics in Construction – The

Insurance Dilemma & Solutions”, tried to address the issue of Plastics in construction

also, and some of the material and recommendations provided by FM Global at these

seminars is summarised within the article also.

Is there really a problem, and if so what is it?

If I had a dollar for every time I had been asked in the last year or so, why are plastics in

construction, or EPS sandwich panels in particular, a problem in fire all of a sudden? I

would probably not be up late at night writing this article before the deadline for

publication, as I would have enough money to live comfortably in a safe house with no

plastics in it!

OK, getting serious now, what is the correct answer to this question?

I will try and give you my views:

Increased use of plastics

No one can argue that over recent decades, the number of plastic materials, and their use

has grown exponentially in all applications. The use of plastics in construction has

grown, as these materials are typically lightweight, durable, weather resistant,

aesthetically pleasing and in most cases cost effective. The problem is that in some

specific, but certainly not all applications which is an important distinction to make, in

the advent of a fire, these plastic materials may contribute to the growth of a fire once it

starts, and result in more intense and rapidly spreading fires compared to more traditional

construction materials, and so called non combustible materials, such as masonry and

concrete.

Changing Insurance environment – investment income cannot sustain underwriting income losses

If the above fact is true, and we have been using plastics in construction for the past few

decades at least, then why all of a sudden, is the insurance industry in Australia and New

Zealand singling out specific plastic construction types, which were being insured at

affordable premium previously, and either refusing insurance or increasing the insurance

premium to ridiculously high levels unless sprinkler and/or other upgrades are

undertaken?

One reason, which was articulated by the insurance industry at the recent seminar series,

is that the insurance industries generally speaking were making underwriting losses

previously, but these were being accounted for by large gains through investment income

(stock market). With the recent stock market collapse and other significant events, like

September 11 and the collapse of HIH locally, the operating environment for insurers is

very different and investment income cannot offset the underwriting losses sustained

previously. The result is increased premiums to ensure underwriting premiums can cover

the claims. The insurance industry suggests that the recent activity is a correction factor,

and that coverage and premiums are no different today than they were in the early 1990’s.

Fires and losses involving plastics in construction

At the recent seminar series, the Munich Re Group provided a good account of real fires,

and fire loss statistics relating to fires involving plastics in construction. These included

both international fires and local fires. Attendees saw copies of videos footage from

actual fires including National News footage from the Tip Top Bakery fire in Sydney,

West Gate Cold Stores fire in Melbourne, and a recent Queensland warehouse fire, all of

which involved the use of plastic materials used in construction of the internal envelope

of the building.

The Munich Re Group regularly publish a publication for external circulation, called

“Schaden Spiegel”, The purpose of this publication is to share relevant information

gleaned from their extensive loss history based on actual fires and actual loss data.

The following quote is from the January 1995 edition in relation to the food industry sub

sector:

Although this category of risk is not generally considered to be particularly susceptible, it

is affected time and again by large fire losses. This is not exactly new to insurers but it is

certainly a costly affair.

In 76 large loss events that we have recorded in the last 6 years, the total losses of

property and business interruption reached nearly US$1.8 billion, the average loss being

about US$ 23 million.

If we cast an eye over the losses of the past years, we will notice a few features which are

particularly characteristic of the food industry.

The fire load in the substance of the buildings themselves

Many foodstuffs must be cooled before, during and after processing. For the process of

cooling to be economical, however, heat insulation is essential and this is a field in which

widespread use is made of combustible materials, e.g. polyurethane in roof areas and

polystyrene in external walls and in partitions. This means that once a short circuit in a

current distribution board ora small fire in an office has set the insulation alight, the

development of toxic fumes and smoke and the danger of collapse leave fire fighters with

no alternative but to retreat and seek shelter in neighbouring buildings.

The most cost effective loss prevention measure is therefore to do without combustible

types of insulation altogether.

Perhaps this anecdotal evidence presented at the recent seminar series by Munich Re

suggest that there has in fact been serious fires involving buildings incorporating plastics

in construction, and that insurance have in fact been paying out large sums of money for

building, contents and business interruption after fires in these facilities, and maybe for

some specific applications, the insurance premiums need to reflect the increased risks of

serious damage in a fire scenario. It would be interesting to be able to compare and

contrast the premium income for these types of buildings for the same period against the

Munich Re Group’s published figures.

I will leave it up to you to decide for yourselves, but the reality is, the above factors have

seen insurance for particular buildings incorporating plastic construction, increase, and

insurers are asking facility owners to improve their fire protection systems and/or the

construction itself to reduce the risk, and therefore be in a position to provide a palatable

insurance premium.

Generic plastic types

At the seminar series, some time was spent differentiating between so called

thermoplastic and thermoset type plastics.

Thermoplastic type plastics soften when heated and reharden when cooled. The process

is reversible. These plastic materials typically melt and burn in fires. Some examples

include acrylic plastics, polycarbonate, PET, PVC and EPS (expanded polystyrene).

Thermoset plastics cure and the process is irreversible. They do not soften and reharden

on cooling. When they burn they typically char. Examples include Polyurethane, (PU),

Polyisocyanurate, (PIR), Fibre Reinforced Plastics, (FRP) and Phenolics.

As a senior CSIRO authority on fire said at the seminar series, it is dangerous to

stereotype plastic materials, and each proprietary formulation and the assembly it is

incorporated into, needs to be proven individually against a fire test protocol that is

relevant to the specific application.

In many ways I feel that the insurance industry generally speaking is guilty of being what

I call “EPS or polystyrene myopic”; that is that they have been known to refuse insurance

or ask for expensive sprinkler upgrades if they are aware of any polystyrene at all in a

facility. Proper risk assessment methodologies and common sense will show that

polystyrene can be safely used in many applications and each instance needs careful

consideration and should be judged based on facts. I know that PACIA, the Plastics

Industry body has an EPS panel group who have done some good work to assist end users

and insurance surveyors understand where and why EPS should and should not be used

and is learning more about the performance of its product in specific applications by way

of serious research programs relating to the effects or otherwise of fire. There have been

many ISO 9705 room corners tests conducted and many of these have in fact met

Building Code of Australia Group 1* requirements. More specific information about

these tests and the recommended applications and system configurations will be available

from the PACIA EPS panel group and may be summarised in a future article in Fire

Australia.

Note that FM Global do not consider the criteria in interpreting the results of the fire testing for BCA

Group 1 as being equivalent to FM Class 1 where other more stringent fire test performance criteria apply.

What do we know about the fire performance of plastics in fire?

There are many fire test methods, new and old that caters for learning more about the

performance of plastics in fire. Some of these are small scale bench types test procedures

and others are larger and/or full scale test methods. Some of the test methods were

discussed in my last article and it is not my intention to go through and compare and

contrast the different test methods here.

FM Global and CSIRO, at the recent seminar series provided participants with some

insights into their capabilities and talked specifically about some of the prevalent test

methods for plastic materials used construction.

The testing in relation to fire deals predominately with a few discrete performance

attributes:

Reaction to fire

Testing in relation to reaction to fire, deals specifically with parameters such as the ease

of ignitability, flammability, spread of flame characteristics, heat evolved and smoke and

toxicity of plastic materials. These properties relate to the contribution of a plastic

material to the growth of a fire that has already started and of course the bi-products of

combustion involving the material. Testing in this area is applicable for wall and ceiling

lining materials.

Figure 1a – Paraphen reinforced phenolic sheet material being tested at small scale level for spread of fire properties (photo courtesy of Alsynite Specialty Products)

Figure 1b – ISO 9705 Intermediate scale room corner test designed for testing spread of fire properties and smoke evolved properties of wall and ceiling lining material assemblies (photo courtesy of CSIRO-MIT)

Fire resistance

Testing in relation to fire resistance is relevant for plastic materials incorporated typically

into composite panels used a fire compartment barriers, designed to contain fires when

they start, from spreading from one building or compartment, to another. These are

typically called a fire wall or a fire rated barriers such as a wall, floor, ceiling or roof.

Typical plastics used in construction

In this section, I have included some applications for plastics used in construction and the

hazards they pose and the associated problems that insurance generally speaking may be

concerned about, and where applicable some of the engineering solutions that may be

applicable to mitigating or reducing the risk of serious damage in the advent of a fire.

Note – This is a summary of material presented by FM Global at the recent seminar series

EPS Sandwich panels

The insurance industry generally speaking does not have its own uniform property

protection code(s) of practice or fire protection guideline(s). FM Global does however

publish comprehensive Datasheets, based on their own requirements, for many specific

fire protection scenarios, which can be purchased, and the in many cases are the basis for

individual insurers own internal guidelines or procedures.

Note – FM Global Datasheets, although very comprehensive and backed by research and historical experience are not the only means of providing acceptable fire protection and developers, building owners and end users should discuss their specific circumstances with their broker or insurance company to be sure of any varying requirements.

Following on from some serious research testing by FM Global Research, the original

version of the FM Data Sheet 1-57 was revised to incorporate the most recent research

work providing sprinkler only protection criteria not contained in the previous version

and was released into the public domain for the first time in Australia and New Zealand

at the seminar series. This revised FM Data Sheet deals with Plastic in Construction

generally, but includes sprinkler only and non-sprinkler fire protection options for

facilities incorporating EPS sandwich panels.

If a fire starts and the EPS sandwich panels themselves get involved in the fire, the fire

can spread very quickly, and unless the correct installation practices and proprietary

panel types have been used, accompanied, where appropriate, by specific fire protection

systems, the fire that results can cause serious damage to a facility.

FM Data Sheet 1-57 provides sprinkler only protection options, which require some

serious water design densities and some specific sprinkler configurations, but none-theless,

are recommended by FM Global as being appropriate for mitigating risk of serious

involvement of the EPS panels themselves in a fire that starts. It must be stressed that the

design densities provided in FM Data Sheet 1-57 are the minimum requirements for the

protection of the structure or the EPS panels themselves, which in most cases for the food

industry exceeds the sprinkler design criteria for the occupancy. However for most high

hazard storage configurations the sprinkler design criteria can exceed what is needed for

the protection of the EPS panels – the higher of the two requirements should always be

provided. It also should be stressed that the research showed that standard sprinkler

system designed to protect the contents, under certain situations will be overrun by the

speed at which fire involving the EPS sandwich panels grows.

FM Data Sheet 1-57 also provides some design upgrade options, for buildings without

sprinklers, again where appropriate (eg sprinklers would not be needed for the occupancy

alone – wet, non combustible food prep area), by ensuring specific EPS sandwich panels

with particular gauges of steel, joint configurations, are fixed adequately to supporting

steel structures and incorporate an additional thermal barrier material fixed to the fire

exposed surface(s).

Note also that the potential of a fire outside of that compartment or external to the building must be considered and if the exposure exists, the outside of the EPS panel would need protection – sprinklers or thermal barriers as well.

Figure 2a – FM corner test being conducted on EPS sandwich panel construction (photo courtesy of FM Global)

Figure 2b – FM corner test being conducted on EPS sandwich panel construction (photo courtesy of FM Global)

PU or PIR sandwich panels

Under the requirements of the revised FM Datasheet 1-57, sandwich panels constructed

of PU or PIR still require sprinkler protection options and/or thermal barriers as per the

requirements for EPS sandwich panels above, however the sprinkler design criteria for

the construction alone incorporating these panel types is less onerous than for EPS panels

due to the thermoset characteristics of these foam plastics

Ideally FM Approved and listed FM Class 1, so-called limited combustible PU or PIR

panels should be provided which have known performance and do not require any

additional specific sprinkler system design apart from what the occupancy requires.

Performance criteria assumed from the generic core material is not recommended as

different formulations and manufacturing techniques can yield very different fire

performance characteristics.

Exposed spray applied Polyurethane

This type of plastic insulation has been shown from FM Global research testing to create

one of the most aggressive and quickly growing fires compared to other plastic lining /

insulation material types. It was commonly used in wineries in particular. The research

showed that no sprinkler only protection options could successfully protect against rapid

fire spread against a fire in this type of installation. The only fire protection design

options provided in the FM revised Datasheet 1-57 are to either fully remove the spray

applied polyurethane material, or to provide an FM Approved spray on protective coating

to fully cover the spray applied polyurethane material.

Figure 3 – Spray applied polyurethane in situ

FRP panels skylights, wall light bands and cladding

Translucent FRP products burn readily and fire spreads even in the most flame retardant

versions, however, in contrast to other translucent plastic materials, they do not typically

sag and droop.

FM Global here regionally, has conducted ASTM E108 testing on some locally produced

proprietary products that suggest they may be treated as FM Class 1 panels. At this point

in time, none of these suppliers have official FM Approval for the products.

Figure 4 – FRP panel being tested to ASTM E108 (photo courtesy of FM Global)

Acrylic & Polycarbonate Skylights, wall light bands and cladding

FM Global research testing using ASTM E108 fire test method shows that these products

melt and droop and care should be taken to ensure that when these are used in roof

applications as skylights, that they have protective mesh installed underneath them to

ensure sprinkler head operation is not impeded. Use as cladding and wall light bands is

limited in FM revised Datasheet 1-57 to small areas separated by non combustible

construction.

EPS panels for high-rise construction facades

The use of this core material is not recommended at all for this application.

There is a fa?ade / curtain wall test method, namely ISO 13785 which may be applicable

for testing fa?ade materials used for high rise fa?ade construction.

External Insulation and Finishing Systems (EIFS)

This is a relatively new construction practice that is popular in Europe and the USA, and

involves polystyrene insulation with polymeric render over the top of it. These types of

systems provide some additional concerns to insurance due to the increased potential for

serious fires during construction due to the amount of EPS exposed.

FM Global have a specific FM Data Sheet 1-63 dealing with EIFS systems that was

provided to participants at the seminar series. The recommendations contained within this

Data Sheet are for staged construction with quick application of the protective outer coat

to reduce amount and time with exposed EPS on the building fa?ade.

Note 1 - EIFS containing EPS with a thickness greater than 25mm adhered to a plasterboard substrate is considered combustible construction by FM Global.

Note 2 – FM Data Sheet 1-63 is based solely on typical USA EIFS systems that in all cases use a plasterboard substrate onto which the EPS is adhered. If however, there is no substrate or a combustible substrate, then the potential of a fire in this material entering the building is virtually a given as opposed to being primarily an external wall fire with some potential of getting into the building and serious insurance ramifications would apply.

There are obviously on going maintenance issues for life of building to ensure the EPS is

covered as some of these systems have been known to be subject to impact damage and

damage from flying debris in storms.

Figure 5 – Typical installation photo of an EIFS system

EPS Insulation / formwork

This is another European common construction technique that is becoming more

prevalent in Australia and particularly New Zealand. It involves using EPS as formwork

and filling it with concrete to form economical walls and floors with sought after acoustic

and thermal properties.

Again, like EFIS above, the concern relate to fire load during construction especially with

ignition sources from other on site trades.

Trades are known to melt or try and burn using an oxy-acetylene torch, trunking holes for

cables and other services which have been known to be the cause of fires during

construction.

About the recent Plastic in Construction Seminar series

Those of you readers who attended the Plastics in Construction seminar series would

agree that it was an outstanding success and I would like to take this opportunity to

congratulate the FPA Australia for organising the event and FM Global, Munich Re

Group, CSIRO, BRANZ and the Alliance for Fire & Smoke Containment for their

involvement as speakers.

The presentation folder / satchels were certainly worth keeping as was the wealth of

information inside them and I would like to thanks the following satchel sponsors, whom

I hit up for some sponsorship money; AU&S Group, Alsynite Specialty Products,

Alliance for Fire & Smoke Containment, Bondor, Borden, PACIA, Promat, Panelcore,

Polyphen and XFlam International.

Acknowledgements

The author would like to thank Andre Mierzwa (FM Global), Jack Kilavuz (Munich Re

Group) and Vince Dowling (CSIRO – MIT) for both their efforts during the seminar

series and also with their editorial assistance in compilation of this article. FPA Australia

and Amy Maney from the Association (in particular), should also be acknowledged for

their efforts in coordinating a very successful seminar series.

About the author

John Rakic is the Principal and Managing Director of J-RAK Consulting (visit

www.rakman.com.au) who amongst other things are actively involved in assisting

manufacturers and suppliers develop, fire test and gain necessary approvals for use their

proprietary fire and smoke containment systems in order to meet relevant regulatory and

insurance requirements. J-RAK Consulting has been involved with the development and

fire testing of many plastic materials used in construction.

John is also the Executive Officer for the Alliance for Fire & Smoke Containment (visit

www.pfpa.com.au).