-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved. © Copyright 2018 Underwriters Laboratories Inc, All
rights reserved.
The Intersection of Research
and Standards
SES Webinar 17 October 2018
J. Thomas Chapin, Ph.D.
Vice President Research
UL Corporate Fellow
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Outline of Presentation
• Introduction to UL
• Public Safety Challenges
• UL Research Platform
• Case Studies
• Q&A
1
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
UL Corporate Structure
UL Not-for-Profit(Underwriters Laboratories)
ResearchStandardsEducation Outreach
UL Commercial(UL LLC)
Development, Testing, Inspection, Certification,
Surveillance,Software,
Advisory Services
UL and the UL logo are trademarks of UL LLC © 20182
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Global Drivers for Safety Research
3
Global Population Growth and
Demographic Change
Economic Development
Urban Planning
Natural Resources
Energy Demand
Environmental Impact
HealthcareFood & Nutrition
Aging
Education & Outreach
ICT/Cybersecurity
Technology
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
UL Commercial & Public Safety Relationships
Manufacturer- Senior Mgmt.
- Design
- Manufacturing
- Quality
- Marketing/Sales
Authorities/Regulators,
Research Laboratories- Code Officials
- Inspectors
- Fire Services
- CPSC / OSHA / EPA
- National Labs
- Universities/Academia
Intermediate Channels- Wholesalers
- Importers / Exporters
• Distributors
Insurance
Companies
Consumers/General Public
Retailers
Components
Raw Materials
4
UL - Independent Standards,
Testing, Certification Organization
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Public Safety Challenges:
the Evolving Definition of Safety
5
+ +
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
UL Research Platform
6
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
University research
partners
Government
research partners
Industry research
partners
Other research
partners
Organization Structure: Global platform for world-class safety
research
Modeling
Physics &
Electrical Safety
Fire Research
Materials Science
NFP Firefighter
Safety Institute
Center of Excellence (CoE) is a combination of expert staff,
equipment and
facilities in a strategic global locations with a defined
research focus. CoE’s
collaborate across geographic and technical boundaries creating
a global
platform for accelerated knowledge generation and discovery
7
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
UL Research & Development Activities
➢ Conduct Fundamental Safety Science Research
➢ Evaluate Emerging Technologies
➢ Develop Test Methods and Revise Standards
➢ Advance Predictive Analysis and Modeling
➢ Develop Education, Training, Outreach Programs
8
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Materials Research - Creating a Reliable Infrastructure
Materials
• Chemicals
• Plastics
• Wood
• Fibers
• Minerals
• Metals, alloys
Components
• Connectors
• Enclosures
• Laminated beams
• Composite boards
• Wiring
• Insulated boards
• Textiles
Real-scale simulations
Field Tests (performance)
Reliability studies
First responder safety
Electrical safety
Code compliance
Environmental compliance
Small-scale tests
Materials
characterization
Performance
Aging/Reliability
Intermediate-scale
Safety
Performance
Aging/Service life
Modeling
Systems
• Lighting
• HVAC
• Energy
• Telecom
• Furnishings
• Wall/Roof systems
• Security
Products
• Electronics
• Appliances
• Trusses
• Furniture
• Wire & Cable
• Air conditioners
• Furnaces
• Lights
Structures
• Residential
• Commercial
• Retail
• High Rise
• Industrial
9
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
UL Analytical (Forensic) Capabilities
CT Scanning System
Field Emission SEM/
EDS Microprobe
FTIR-Microscope
Pyrolysis GC-MS
TGA-MS/IR, mTGA
DSC
DMA
PDSC
10
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Electrical Research: Small Issues Lead to Big Ones
Small phenomena
occur, such as
overheating, arcing,
harmonics, etc…
…Leading to corrosion,
aging, failure, etc. Then
interactions occur
eventually leading to
system-wide failure…
…leads to
deaths,
injuries,
property loss.
Prevention:
• Understand
the science
• Understand
failure mode
interactions.
• ID key points
for mitigation
• Address via
standards,
regulations,
training, etc.
11
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
PV Standards … materials, components, products
Materials Components Products System Installation
12
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Padova/Italy, 2009
Roof: 1,400 m2
System: 100 kW
Partial shading
13
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Upholstered Furniture Flammability – Test Scale
14
material-level tests
mock-up tests
furniture tests
Living room flashover tests
(Phase II)
Tenability and survivability tests
(Phase III)
Phase I
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Safety Science Research Assessments
15
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Mitigating Fire Risks
v Safety in Design
v Product
Certification
v Construction
codes
v Maintenance and
housekeeping
Precipitating
Hazard
Ignition
Sources
Fuels
Enabling
Hazards
Vulnerability
HazardFire Impact
PREVENTING THE FIRE MANAGING THE FIRE EVENT
v Intentional
v Human error
v Equipment
malfunction
v Chemical
reaction
v Internal sources
v External sources
v Combustible
items
v Additional
combustible
materials
(furnishings, interior
finish, etc.)
v Fire and smoke
paths through
building structure
v Fire spread to
adjoining areas
v Smoke spread
v Blocked agress
paths
v Fire spread to
adjoing buildings
Fire growth
control
Life safety
and
property
protection
Fire
mitigation
v Injuries/
fatalities
v Property
Loss
v Reduced oxygen
environment
v Aspirated gas
and smoke
detection
v Fire
extinguishment
systems
v Fire resistance
v Fire containment
v Egress paths
v Designated safe
zones
v Firefighter access
v Emergency
service response
v Search and
rescue
Ignition
Event
Preventive
measures
Tools
Strategy
NFPA 55016
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Hazard-Based Safety Engineering
Hazardous
Source
Transfer
Mechanism
Harm
HBSE Premise
No
No
IDENTIFY ENERGY
SOURCE
IS SOURCE
HAZARDOUS?
IDENTIFY MEANS BY WHICH
ENERGY CAN BE
TRANSFERRED TO A BODY PART
DESIGN SAFEGUARD WHICH
WILL PREVENT ENERGY
TRANSFER TO A BODY PART
MEASURE SAFEGUARD
EFFECTIVENESS
IS SAFEGUARD
EFFECTIVE?
DONE
Yes
Yes
HBSE Process
ENERGY TRANSFER
INJURY
AND
INADEQUATE
PERSONAL
SAFEGUARD
PERSONAL
SAFEGUARD
FAILURE
NO
PERSONAL
SAFEGUARD
OR
INADEQUATE
PERSONAL
AVOIDANCE
AVOIDANCE
NOT
POSSIBLE
AVOIDANCE
NOT
ATTEMPTED
OR
BODILY
EXPOSURE
AND
INADEQUATE
EQUIPMENT
SAFEGUARD
EQUIPMENT
SAFEGUARD
FAILURE
NO
EQUIPMENT
SAFEGUARD
OR
INADEQUATE
EQUIPMENT
SAFEGUARD
EQUIPMENT
SAFEGUARD
FAILURE
NO
EQUIPMENT
SAFEGUARD
OR
HAZARDOUS
ENERGY
AND
(EVENT)
OR
(EVENT)
OR
HBSE Standard Injury Fault Tree
Haz?
How?
Prot
how?
How
well?
HarmSource:
energy /
substance
Harmed
Part
17
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Systematic Approach
• Define, Analyze, Validate, Test, Control
• Safety, Risk, Harm, Hazard
• Risk Management
• Analyze, Estimate, Evaluate, Reduce, Control
• Systems Engineering
• Subsystems, Components, Environment: interfaces /
interactions
• Lifecycle: Design, Production, Assembly, Storage,
Transport,
Installation, Use, Service, Disposal, etc.
• Disciplined Analysis: Harm, Hazard, Fault / Failure
• Means of Harm – root causes, conditions, events,
mechanisms
• Means of Protection – focused on specific means of harm
– Identify, validate, control protective properties
– Maintain safety attributes: efficacy, durability,
reliability
Risk
S
O
18
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
FTA Safety Model - Overview
Based on standard
format / guidelines
e.g., Fault Tree Handbook
US NRC, NASA, etc.
Example Fault Tree (overall view):
19
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
FTA / Safety Model Characteristics
FTA, Fault Tree Analysis
▪ Systematic, deductive (top-down), general specific
▪ Qualitative / quantitative … comparative
IN: Top event fault (what, how)
OUT: Root cause, contributing, precipitating or cascading
conditions / events, and how to prevent or mitigate
FTA, Fault Tree Analysis Safety FTA Model
▪ Safety, not other functional aspects
▪ Model – necessarily broader than specific analysis
▪ Purpose / Intent – One size fits many
20
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
FMEA Safety Model - Overview
Based on standard
format / guidelines,
e.g., SAE J1739, etc.
(adapted for application)
Example FMEA (overall view):
21
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
FMEA / Safety Model Characteristics
FMEA, Failure Modes and Effects Analysis
▪ Systematic, inductive (bottom-up), specific general
▪ Qualitative / quantitative … comparative
IN: Identify items (e.g., components, materials) and their
functions in various conditions (e.g., operating. modes), and
determine each failure mode
OUT: Potential effects, causes and protective means
FMEA Safety FMEA Model
▪ Safety, not other functional aspects
▪ Model – necessarily broader than specific analysis
▪ Purpose / Intent – One size fits many
22
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Combining FTA and FMEA Principles
▪ Safety Analyses: systematic & robust
▪ Integrated FTA / FMEA Safety Models:
• Methodically analyze and reduce risk
• Complementary: more effective predictive modeling
• Scalable: simple to complex
• Identify / prioritize specific means of protection
• Prevent occurrence and/or mitigate severity
Mutual Benefits:
▪ Demonstrate Safety Improvements
▪ Tie Together Conducted Research
▪ Identify / Prioritize Future Research
23
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Safety Science Research Projects
- Smoke Research
- Li Battery Research
24
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
What is “Smoke”?
Smoke Aggregation and Aging
Alarm Response Characteristics
Egress Time Analysis
Firefighter Exposure
Nuisance Alarm Criteria
UL Smoke Research – Particles, Gas-Phase Analysis
Revisions to UL 217 &
UL 268 Standards
25
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Factors Driving UL Research Focus – Why?
Role of Building Contents and Materials:
• Increased quantities of combustibles in homes
• Increased percentage of imported goods (unknown chemistry)
• Increased usage of synthetic (vs natural) materials
• Regulatory actions on mattresses, upholstered furniture, bed
clothing and furnishings
Smoke Detector Performance Gaps:
• Use (96% homes have alarms)
• Effectiveness (focus on faster developing fires and
smoldering fires, improved nuisance discrimination)
• Reliability (20% of installed alarms are inoperable)
26
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Impact of Fire in Residential Buildings1
1USFA One- and Two-Family Residential Building Fires
(2011-2013), Volume 16, Issue 4 / June 2015
1. Annual estimate for 1,2 - family residential building
fires: 241,700
2. Human impact: 2,025 deaths, 8,400 injuries
3. Economic impact: $5.8B USD property loss
27
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Major Causes of Residential Building Fires1
1USFA One- and Two-Family Residential Building Fires
(2011-2013), Volume 16, Issue 4 / June 2015
Cause Percentage
Cooking 35.0
Heating 16.2
Electrical Malfunction 8.4
Other intentional, careless 7.6
Open Flame 5.8
Intentional 5.8
28
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Leading Areas of Fire Origin1
1USFA One- and Two-Family Residential Building Fires
(2011-2013), Volume 16, Issue 4 / June 2015
Area of Fire Origin Percentage
Kitchen 18.3
Bedrooms 12.7
Den, Family Room, Living Room, Lounge 6.7
Attic 5.7
Exterior Wall Surface 5.5
Laundry area 5.1
Garage, car port 5.0
29
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Material Chemistry (Home Contents as Fuel)
• Natural materials - (cotton, wool, silk, wood, etc.) -
Tend
to char on heating and retard decomposition)
• Synthetic materials - (polyolefins, acrylics, nylons,
polyesters, etc.) – Derived from crude oil and tend to
melt, drip and char on heating, higher heat of
combustion and heat release
• Blends (physical, chemical) - Exhibit a range of ignition
and burning behavior
• Additives and surface treatments - Alter decomposition,
and burning characteristics
30
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
UL Smoke Research Objectives
1. Characterize the chemistry, thermal decomposition and
combustibility of materials found in residential structures.
2. Characterize smoke characteristics (gases, particles) for
materials found in residential settings for both smoldering and
flaming modes of combustion.
3. Develop recommendations for changes to the current smoke
detector standard (UL 217).
31
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Selection of Representative ProductsResidential Space Typical
Products
Appliance wiring
Bed clothing
Candles
Carpeting
Drapes
Mattress
Paper products
Plastic enclosures for electrical products
Upholstered furniture
Wall paper
Wood furniture
Appliance enclosures
Appliance wiring
Cabinets
Cooking materials
Counter tops
Food containers
Foods
Wall paper
Paints
Fuels
Packaging materials
Bedroom and Living Room
Kitchen
Storage Areas
32
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
FTIR Analysis
Spectral transmission and absorption analysis
in the infra-red region (600 to 4000 cm-1)
provide a “finger print” for materials
Number of sample scans: 32
Number of background scans: 32 Resolution: 4.000 Sample gain:
8.0 Mirror velocity: 0.6329
Aperture: 100.00
Detector: DTGS KBr Beamsplitter: KBr Source: IR
Operator:
Underwriters Laboratories, 3019DFPD
Collection time: Thu Feb 03 09:28:31 2005 (GMT-06:00)
ABESCO
FC
60
65
70
75
80
85
90
95
100
%Transmittance
500 1000 1500 2000 2500 3000 3500 4000
Wavenumbers (cm-1)
FP200 FR EXPANDING (B1 PU) FOAM, 48 HR OPEN AIR CURE
05NK03894 DATA:R21538_020305_GG.SPA REF DATE:F02-03-05
33
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Differential Scanning Calorimeter (DSC)
• Precise furnace temperature control
• Endo and exothermic characteristics
• Melting temperature, glass transition temperature
• 10 to 30 mg sample
Temperature (oC)
100 200 300 400 500
Heat F
low
(m
W)
48
50
52
54
56
58
60
62
64
66
34
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Heat of Combustion, (Hc)
Oxygen bomb
calorimeter• Polyethylene
• Polyester
• Polyurethane
• Nylon
• Wood
• Plasticized PVC
• Rigid PVC
• Brick
• Parr Bomb Calorimeter, 1 mg sample
• High pressure, oxygen environment
• Heat of combustion of materials:
35
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
36
Cone Calorimetry
• Radiant heat flux to 100 kW/m2
• 100 x 100 mm sample
• Ignition
• Heat release
• Smoke release
• Weight loss
• Test Standards
- ASTM E1354
- ISO 5660
- NFPA 271
- CAN/ULC S-135
• Allows extraction of gases for smoke
and gas effluent analysis
• Data from Cone Calorimeter may be
employed in fire models such as FDS
36
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Cone Calorimeter Data
0
50
100
150
200
250
300
350
400
450
0 100 200 300 400 500 600 700
Time (s)
HR
R (
kW
/m²)
0
10
20
30
40
50
60
70
80
90
100
We
igh
t F
ractio
n (
%)
HRR
Weight %
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0 100 200 300 400 500 600 700
Time (s)
SR
R (
m²/
s)
0
10
20
30
40
50
60
70
80
90
100
We
igh
t F
ractio
n (
%)
SRR
Weight %
Heat Release Rate
(HRR)
Smoke Release Rate
(SRR)
37
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Sampling Method
N2dilution
FTIR
Every 15 s
Smoke Particle
Every 67 s
Calorimeter
38
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Instrumentation: Smoke Particle Size
MSP Corporation Model WPS 1000XP
• 0.01 – 10 μm size range
- 0.01 – 0.5 μm (DMA)
- 0.35 – 10 μm (LPS)
- Calibration using NIST
traceable PS latex spheres
• Dynamic sampling and analysis
- 48 size ranges
- Measurements every 67 seconds
- Concentration limited to 2 × 107 particles/cc
39
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Smoke Particle Analysis
PET Carpet
11
17
26
40
63
10
2
16
9
29
7
36
0
44
5
57
5
90
0 048
115182
249316
383450
517584
0.0E+00
2.6E+05
5.1E+05
7.7E+05
1.0E+06
1.3E+06
Pa
rticle
de
nsity
(1/c
c)
Particle Size (nm)
Time (s
)
40
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Key Findings – Comparison of Flaming vs
Smoldering Combustion (Particulates)
0.00
0.05
0.10
0.15
0.20
0.25
0.30
Coo
king
oil
Bre
ad
New
spap
er
Dou
glas
fir
Pon
dero
sa p
ine
Cot
ton
batting
Cot
ton/
Polyes
ter b
lend
(fab
ric)
Ray
on (f
abric
)
HDPE
Nylon
car
pet
Polye
ster
car
pet
Polye
ster
fillin
g
PU fo
am
Polyiso
cyan
uara
te fo
am PVC
Me
an
Pa
rtic
le D
iam
ete
r (m
icro
n)
Flaming
Non-Flaming
UL 217 materials
41
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Coo
king
oil
Bre
ad
New
spap
er
Dou
glas
fir
Pon
dero
sa p
ine
Cot
ton
batting
Cot
ton/
Polyes
ter b
lend
(fab
ric)
Ray
on (f
abric
)
HDPE
Nylon
car
pet
Polye
ster
car
pet
Polye
ster
fillin
g
PU fo
am
Polyiso
cyan
uara
te fo
am PVC
Sp
ecific
Extin
ctio
n A
rea
(m
²/g
)
Flaming
Non-Flaming
UL 217 materials
Key Findings – Comparison of Flaming vs
Smoldering Combustion (Smoke)
42
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Key Findings - Gas Analysis and Smoke
Characterization Measurement
Smoke Particle Aggregation - Tests conducted in
the UL 217 Sensitivity Test smoke box and the UL
217/UL 268 Fire Test Room indicate an
aggregation of smaller smoke particles to form
larger particles as evidenced by the increase in
smoke particle concentrations in conjunction with
increasing fractions of larger smoke particles. This
was more evident for non-flaming fires (smoldering)
than flaming fires.
43
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Key Findings - Gas Analysis and Smoke
Characterization Measurement
Smoke Gas Effluent Composition - Gas effluent analysis
showed the dominant gas components were water vapor,
carbon dioxide and carbon monoxide.
Water CO2 CO
SO2 NO2 Methane
Ammonia Phenol Styrene
Formaldehyde HCN Propane
HCl HF Ethylene
Acrylonitrile
44
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Key Findings - Influence of Material Chemistry
• Combustion Behavior: Synthetic vs Natural Materials –
Cone calorimeter tests indicate synthetic materials (e.g.
polyethylene, polyester, nylon, polyurethane) generate
higher heat and smoke release rates than the natural
materials (e.g. wood, cotton batting). This is anticipated
to be primarily due to the modes of degradation and
chemical structure of synthetic versus natural materials.
• Charring Effects - Materials exhibiting charring behavior
such as wood alter the size and amount of smoke
particles generated as the combustion process
progresses.
45
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Key Findings - UL 217/UL 268 Fire Test Room Tests
• Influence on Smoke Particle Size - In general, the
synthetic materials generated larger mean smoke
particle sizes than natural materials in flaming mode.
• Smoke Stratification - Non-flaming fires result in
changes in the smoke build up over time, such that
stratification of smoke below the ceiling occurs. This
time-dependent phenomenon results in less obscuration
at the ceiling than below the ceiling. This caused both
detection technologies to drift out of alarm.
46
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Outcome of Smoke Characterization Research
1. UL Smoke Characterization Project has produced extensive
new knowledge about smoke characteristics.
2. Each material (or combination) as a unique “fingerprint”
composed of gases, particle chemistry and size distribution.
3. This “fingerprint” varies with the mode of ignition
(smoldering vs flaming).
4. The dominant factor of the smoke fingerprint is dictated
by
chemical composition (polymer chemistry and additives).
5. Synthetic materials (derived from crude oil) tend to
soften,
liquefy and decompose rapidly (depolymerize).
6. Natural materials (more complex composition) tend to char
and decompose in a more complex fashion.
7. Major changes to UL 217 were made from this research.
47
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Evolution of Battery Technologies
2016
2005
2008
2010
48
1985
Batteries in end products require independent,
third party certification
• Formats: button, cylindrical, prismatic, pouch
• Laptops (Required)
• Cell Phone Batteries
• Appliances, Power Tools and Consumer Products
• Light EV Batteries and Systems
• Commercial / Industrial Transportation / EVs
• Stationary Batteries / Energy Storage
2018
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Cell Failure and Internal Short Circuit Behavior
Dendrite
Process
Issue(s)
Mechanical
Abuse
Unstable
Design
Internal
Short-Circuit
Overcharge
Imbalance
DropCrush
Material
Properties
Impact
Shock / Vibration
Contamination
Burrs
Other (bad welds,
loose metal parts, etc.)
Severe
EnvironmentAbnormal
Pressure Abnormal
Temperature
Tab/electrode
misalignment
Improper
Separator
Over design
Handling
Use
ManufactureOperation
Design
49
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Typical Localized Failure Mechanism in an ISC
Heating is triggered locally in the
beginning at ISC point. However, the
active material at the ISC point can
usually become less active due to the
electrochemical reaction
Active materials surrounding the ISC
point is still at high chemistry potential
that is more active while suffering a
over-heating propagating from the ISC
point
50
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Thermal Decomposition of Cell Components
51
-
The full report is at
http://www.ntsb.gov/investigations/AccidentReports/Reports/AIR1401.pdf
Boeing 787 Battery Functions
52
Main Battery
• Powers airplane systems before APU or engines start,
• Supports refueling and other ground requirements,
• Emergency power source for instruments and
electric braking systems.
Auxiliary Power Unit (APU) Battery
• Power to start APU, back-up electrical
power in flight, and power on ground.
52 52
-
The full report is at
http://www.ntsb.gov/investigations/AccidentReports/Reports/AIR1401.pdf
Three Boeing 787 Aircraft Incidents
53
Boston, Mass Takamatsu, Japan Narita, Japan
Date: January 7, 2013 January 16, 2013 January 14, 2014
Battery
version:
“-901” (original) “-901” (original) “-902” (redesign with
containment box)
In-flight or
on ground
Ground Flight Ground
Position APU Main Main
Airplane-
level result
Smoke in cabin in
unpowered airplane.
Thermal damage near
battery. One fire fighter
minor injury.
Precautionary
landing. Some
passengers smelled
the failure.
Venting of battery in
containment box was
vented overboard.
Battery-
level result
Venting propagated
through all 8 cells.
Venting propagated
through all 8 cells.
One cell vented. No
propagation.
Fleet grounded January 16 - April 26, 2013
Battery modifications and enclosures added for return to
flight.
53 53
-
The full report is at
http://www.ntsb.gov/investigations/AccidentReports/Reports/AIR1401.pdf
787 incident at Boston, January 7, 2013
54
• 14 Months after 787 introduced
• 3 Weeks after airplane delivered
• Airplane on ground with APU power
• Cleaning crew, mechanic, manager
• Smoke event for about 45 minutes
• Minor burn to one firefighter
• Normal access through floor
APU battery removed
Sketch by mechanic
who saw flame
54
-
The full report is at
http://www.ntsb.gov/investigations/AccidentReports/Reports/AIR1401.pdf
NTSB Investigation Results
• Investigation complete and NTSB report is in public docket
• Multiple potential causes for cell internal short circuit
• 23 safety recommendations include: • To FAA: approach to new
technology, certification process,
certification
• For designers: BMU monitoring, impact, adoption of
industry
design standards, worst case testing/validation at aircraft
level
• Future research needs: development of new design and
safety standards, cell isolation/mitigation, battery failure
impact on digital avionics
5555
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Aviation Normal Flight Profile Assumed Risk
22% 61%
Source: Flight Safety Foundation
56
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Aviation Risk Transporting Batteries
Time from Fire to Loss of Control:
17-19 Minutes
Source: Transport Canada
“Smoke on aircraft is more serious than an engine shutdown”
Capt. Bob Brown, IPA UPS Airlines
57
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Mitigate Emerging Hazards
58
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
Summary and Conclusions
1. UL has a 124-year history of involvement in public safety
with research, testing, standards and surveillance
programs.
2. Public safety is a dynamically changing driven by
socioeconomic, technical and environmental challenges.
3. Discipled approaches exist (HBSE, FTA, FMEA) to
identify potential hazards by trained scientists and
engineers optimally organized in matrixed teams.
4. Exploring the “boundaries of safety” requires long-term
vision, expert staff, sophisticated equipment and
facilities.
5. The reward of this journey is most often embodied in new
and revised standards, education and outreach programs.
59
-
© Copyright 2018 Underwriters Laboratories Inc, All rights
reserved.
THANK YOU
60