Part of the BRE Trust

A Fire Safety OverviewBRE Trust/BPVA WorkshopPhotovoltaics and Fire: Separating fact from fiction 12th July 2011, BRE, Watford

Martin ShippTechnical Development Director, Fire Safety, BRE Global

Electricity can cause fires

Fire Statistics; electrical firesAll dwelling fires: proportion of electrical and non-electrical fires

electrical fires

chip/fat pan fires

other fires

All dwelling fires: proportion of electrical and non-electrical fires .

electrical fires

chip/fat pan fires

other fires

Fire Statistics; electrical firesElectrical fires in dwellings: proportion of fires due to different causes

faulty fuel supply

faulty lead

faulty appliance

misuse

play or carelessness

heat source too close

other cause

Electrical fires in dwellings: proportion of fires due to different causes

faulty fuel supply

faulty lead

faulty appliance

misuse

play or carelessness

heat source too close

other cause

Fire Statistics; electrical firesElectrical fires in dwellings, proportion of fires from different items first ignited

Electric cookers

Microwave cooker

Other electric cooking appliance

Electric space heater

Electric central heating

Electric water heating

Electric welding & cutting appliances

Electric blowlamp

Washing machine

Dishwasher

Refrigerator

Tumble driers

Spin driers

Lighting

Blanket or bedwarmer

Television

Iron

Audio visual

Computer or VDU

Kettle,Urn,etc

Other electrical

Electrical fires in dwellings, proportion of fires from different items first ignited

Electric cookers

Microwave cooker

Other electric cooking appliance

Electric space heater

Electric central heating

Electric water heating

Electric welding & cutting appliances

Electric blowlamp

Washing machine

Dishwasher

Refrigerator

Tumble driers

Spin driers

Lighting

Blanket or bedwarmer

Television

Iron

Audio visual

Computer or VDU

Kettle,Urn,etc

Other electrical

Many new sustainable/environmentally friendly technologies have fire safety implications

• Modular construction

Many new sustainable/environmentally friendly technologies have fire safety implications

• Modular construction

• Timber frame

Many new sustainable/environmentally friendly technologies have fire safety implications

• Modular construction

• Timber frame

• Structural Insulated Panel Systems

Many new sustainable/environmentally friendly technologies have fire safety implications

• Modular construction

• Timber frame

• Structural Insulated Panel Systems

• Engineered joists

• Cladding systems

• Wind generators

Many new sustainable/environmentally friendly technologies have fire safety implications

• Do all new technologies introduce new fire risks?

The issues for PVs

– PV systems can cause fires: fact or fiction?

– PV systems exacerbate fire hazards: fact or fiction?

– PV systems present new electrical risks to firefighters: fact or fiction?

With the permission of Bodo Wolters

PV systems can cause fires: fact or fiction?

– DC not AC

– Installation requires new skills

– Quality of installation critical

– Risk of “cowboy” installers?

– Maintenance important

î

PV systems exacerbate fire hazards: fact or fiction?

– Falling glass

î

PV systems exacerbate fire hazards: fact or fiction?

– Falling glass

– Roof loading (added risk of structural collapse due to weight of panels)

î

PV systems exacerbate fire hazards: fact or fiction?

– Falling glass

– Roof loading (added risk of structural collapse due to weight of panels)

– Poorly installed panels may obstruct/restrict use of roof windows as means of escape

– windows as means of escape

– Fire spread to other properties from panel materials

PV systems present new electrical risks to firefighters: fact or fiction?– Potentially very high DC

voltages (1000 volts?) - more dangerous than normal electrical installations

– Always live – can only shut off utilities, not supply to the inverter

– Shock risk if cables or conduits are cut

– Shock risk from batteries– Shock risk down water jet– (e.g. Switzerland 2002) î

PV systems present new electrical risks to firefighters: fact or fiction?

– Fire fighters may not recognise PV system – lots of different types

– Fire fighters not used to dealing with DC

– Don’t know what to expect

PV systems present new electrical risks to firefighters: fact or fiction?

– Fire fighters may not recognise PV system – lots of different types

– Fire fighters not used to dealing with DC

– Don’t know what to expect– AC detectors will not detect

DC?– Will there be an emergency

switch?– Where?– What if not ?

PV systems present new electrical risks to firefighters: fact or fiction?– Fire fighters may not recognise

PV system – lots of different types

– Fire fighters not used to dealing with DC

– Don’t know what to expect– AC detectors will not detect

DC?– Will there be an emergency

switch?– Where?– What if not?– Confusion with solar thermal?

Heavy metals released: fact or fiction?

– Cadmium Telluride? CdTe

– Only a problem if exposed to very high temperatures? 1100 deg C – seldom reached in uncontained fires.

– Gets encapsulated by glass?

Stories from US

– Firefighters cut through panels to vent fire -electrocution

– Panels prevent venting

– Panels may be slippery – hazard for fire fighters on the roof

– May limit access to and use of roof

– Looking at use of portable covers

Stories from Germany

– 1000 volts DC down hose?

– German firefighters refused to fight fires involving PVs

PV systems can cause fires?

– Installation guides recognise fire risks

PV systems can cause fires?

– Installation guides recognise fire risks

PV systems can cause fires?

– Installation guides recognise fire risks

– Cut off switches on the market

PV systems present new risks to firefighters?

– Other countries have produced guidance– US– Germany

PV systems present new risks to firefighters?

– Other countries have produced guidance

– Not aware of any problems/issues in UK (yet)

– Problem for fire risk assessors – how to assess risk?– risk assessors need

guidance– UK needs guidance to reflect

UK firefighting practice?

Fire and Rescue Service Operational GuidanceGRA 3.1 Fighting fires in buildings

– ELECTRICAL SYSTEMS ON EXTERNAL BUILDING FASCIAS

– Electrical systems may be found in external positions on buildings.

– These may include photo-voltaic panels and shop signs etc which present an electrical shock hazard, or shock track (electric) bird abatement systems, which although only being low voltage, may be hazardous if a firefighter were to touch it whilst at the head of a ladder.

Conclusions

– We need to ensure that all innovations in designs, products and materials that are supporting more sustainable and environmentally friendly buildings do not introduce unexpected fire risks.

– There may be some new fire risks associated with photovoltaics.

– Some of the concerns may be unfounded; others may need a response.

– We need to all work together to ensure that the fire issues are dealt with logically and professionally and not subject to simple commercial pressures.

– We need to all work together to develop practical solutions, and practical guidance.

Thank you

Martin Shipp, Technical Development Director, Fire SafetyBRE GlobalT: +44 (0) 1923 664960E: shippm@bre.co.ukF: +44 (0) 1923 664910W: www.bre.co.uk/fireBRE, Garston, Watford WD25 9XX, UK