Fire Safety in Electrical Engineering & Electronics (E&E)

Report
Fire Safety Requirements, Standardization and Testing
Electrical & Electronic Equipment
Status and Trends
Presentation given at Tokyo,
9 September 2014
Fire safety E&E Tokyo, September 2014
Fire Safety in Electrical Engineering & Electronics (E&E) in Europe

In E&E, general safety requirements including fire safety are defined in the European Low
Voltage (LVD) and the Electromagnetic Compatibility (EMC) Directives

Specific fire safety requirements (in the EU: essential requirements) and flammability tests
are contained in international standards (IEC, CENELEC for the EU), and the corresponding
national standards

Manufacturers set up Document of Conformity (DOC) based on Technical Files
Fire safety E&E Tokyo, September 2014
Fire Safety in Electrical Engineering & Electronics (E&E)

The main flammability tests for E&E are the Bunsen burner based UL 94 tests and the
glow
wire tests. They basically reflect primary, low energy ignition sources inside of
E&E
equipment

External, candle-like ignition sources igniting E&E equipment from the outside have been
considered for consumer and IT electronics. They have been introduced in Europe

Flammability requirements in E&E mainly apply for IT, audio/video, appliances, technical
parts and lighting

The flammability test requirements are basically UL 94 HB, V2 to V0.
In addition the needle flame test may be used

For appliances, the glow wire tests are largely used in Europe
Fire safety E&E Tokyo, September 2014
Course of a fire and small ignition sources
Small ignition sources are the cause of most fires. Preventing and delaying their impact
Is essential to avoid flashover
Fire safety E&E Tokyo, September 2014
Fire Safety in Electrical Engineering & Electronics (E&E)

The main flammability tests for E&E are the Bunsen burner based UL 94 tests and the
Needle Flame test
Vertical test to IEC 60695-11-10
(UL 94 V0, V1, V2) 50 W flame
Test to IEC 60695-11-20
(UL 94 , 5VA, 5VB) 500 W flame
Needle Flame test to IEC 60695-11-5
Fire safety E&E Tokyo, September 2014
Appliances
Glow Wire Test

The European standard EN 60335-1 ”Household and similar electrical appliances – Safety”
addresses fire safety requirements in Section 30 “Resistance to Heat and Fire”

The most important flammability test for appliances in Europe is the glow wire test
Fire safety E&E Tokyo, September 2014
Requirements to IEC 60695-2-11 to -13
Unattended Connection > 0.2 A

IEC/EN 60695-2-11 Flammability end products (GWT)
750°C < 2 s required in IEC 335

if > 2 s Needle flame test to IEC 60695-11-5 or
Class V0 or V1 to IEC 60695-11-10

IEC/EN 60695-2-12 Flammability materials (GWFI)
850°C < 30 s

IEC/EN 60695-2-13 Ignitability materials (GWIT)
775°C < 5 s
Fire safety E&E Tokyo, September 2014
Glow Wire Standards to IEC 60695-2 revised in 2013

IEC/EN 60695-2-10 (VDE 0471-2-10) Glow wire
Apparatus and common test procedure

IEC/EN 60695-2-11 (VDE 0471-2-11) Glow wire
Flammability test for end products (GWT)

IEC/EN 60695-2-12 (VDE 0471-2-12) Glow wire
Flammability test for materials (GWFI)

IEC/EN 60695-2-13 (VDE 0471-2-13) Glow wire
Ignitability test for materials (GWIT)
No major changes in the revised standards
Fire safety E&E Tokyo, September 2014
External ignition sources

External ignition sources for consumer electronics and IT equipment were developed in the
technical specification IEC/TS 62441 “Accidentally caused candle flame ignition” and foreseen
to be introduced in the IEC 60065 standard

The TS describes fire hazards from external ignition sources, requiring materials (> 300 g) to
meet Class UL94 V1

However, its introduction has been rejected by an IEC vote in 2010, following an American
NGO activists’ campaign against flame retardants

At the same time, it has been taken over in the corresponding European EN 60065 standard
Fire safety E&E Tokyo, September 2014
Fire Safety in Electrical Engineering & Electronics (E&E)

The revision of the new standard IEC 62368-1 “Audio/video, information and communication
technology equipment - Part 1: Safety requirements” also considers external ignition sources

IEC 62368 is a merger of the standards IEC 60065 for consumer electronics and IEC 60950-1
for IT equipment and will substitute them

In a new campaign, the same activists succeeded again to initiate a negative vote, so that the
introduction of the external ignition sources in IEC 62368-1 has been rejected in May 2012

These campaigns against flame retardants in general may
reduce the fire safety levels of consumers and IT equipment
in the future and lead to increased threats to human life
and material damages
Fire safety E&E Tokyo, September 2014
may dram
Fire Safety in Electrical Engineering & Electronics (E&E)

The dramatic effects of external ignition sources on TV sets is shown in the following videos
Videos (to be included into the presentation)
Test on television 32 inch
Test on television 40 inch
Fire safety E&E Tokyo, September 2014
Fire tests wire & cable

IEC 60332-1: Tests on electric and optical fibre cables under fire conditions - Part 1-2: Test for
vertical flame propagation for a single insulated wire or cable - Procedure for 1 kW pre-mixed
flame (IEC 60332-1-2:2004)

IEC 60332-2. Part 2-2: Test for vertical flame propagation for a single small insulated wire or
cable - Procedure for diffusion flame (IEC 60332-2-2:2004)

IEC 60332-3. Tests on electric and optical fibre cables under fire conditions - Part 3: Test for
vertical flame spread of vertically-mounted bunched wires or cables

Modified IEC 60332-3 Test for construction products: EN 50265-2-1/2 with hood for
measuring rate of heat release (Basis FIPEC)
Fire safety E&E Tokyo, September 2014
Fire tests wire & cable
Flame propagation tests to IEC 60332-1 and -2
IEC 60332-1: Single insulated wire
IEC 60332-2: Single small insulated wire
Fire safety E&E Tokyo, September 2014
Fire tests wire & cable
Modified IEC 60332-3 Test for construction products:
EN 50265-2-1/2

Flame propagation

Heat release (O2 consumption)

CO2 concentration

Smoke measurement
Fire safety E&E Tokyo, September 2014
Photovoltaics: Problems for fire safety

Photovoltaics (PV): Generating electrical power by converting solar radiation into direct current
electricity

Light is converted into electrical power by semi-conductors

Several inter-connected solar cells form a solar module

Although fire safety problems do not occur frequently,
they may take place more often in the future
because of the increasing growth of this technology
Fire safety E&E Tokyo, September 2014
Photovoltaics: Problems for fire safety

In 2009, the world largest photovoltaics roofing site took fire in Bürstadt, Germany,
destroying 80 m² of the solar modules

Fire causes are frequently faulty electrical connections within the modules leading to
overheating and fire initiation
Fire safety E&E Tokyo, September 2014
Photovoltaics: Problems for fire safety

To date, only limited experience of fire brigades in PV-equipment fires

Problem: Due to light radiation, solar modules and their components are virtually
always live with direct current voltage up to 1,000 V

This may lead to deadly electrical shock during fire-fighting

To this end, guidelines and data sheets have been published. Standardization however,
is still in its infancy
Fire safety E&E Tokyo, September 2014
Conclusions

E&E ignition/flammability tests address the beginning of an initiating fire

They have shown to prevent or delay fires from E&E materials and end products

Fire tests simulating open flames and malfunction of electrical parts (glow wire) have
shown to be very effective

External open flame tests for consumer/IT devices help to improve fire safety

Tests for wire & cable flame propagation contribute to fire safety in many applications
for building/construction and transportation

Photovoltaics fire safety is of growing importance
Fire safety E&E Tokyo, September 2014

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