Title: Risk Assessment using Scoring System Methodology (SSM) as holistic substitute for IBC Height
1Risk Assessment using Scoring System Methodology
(SSM) as holistic substitute for IBC Height
Area Table
- Frank Noonan
- Professor of Industrial Engineering Fire
Protection Engineering - Worcester Polytechnic Institute
- For AFSCC, 8/3/07, Chicago, Il.
2The challenge
- HA Table overly prescriptive?
- Incomplete with respect to assessing all relevant
factors that make a given building size safe or
unsafe. - Goals
- Holistic approach.
- Acceptable level of fire safety for communities,
occupants, emergency responders.
3Scoring System Methodology
- Widely used throughout global economy for risk
assessment. - Pioneered by banking industry to assess
likelihood for default with loan applications. - Other applications
- IRS audit decisions
- Parole board decisions
- Mass mail and telemarketing decisions
- Insurance industry customer screening
- Hospital patient procedure decisions
4Scoring Model Example
Risk Index
Explanatory Level
Factors Data
Very Poor Risk Poor Risk Medium Risk Relatively
Good Risk Good Risk Very Good Risk
-Personnel Experience -Material Handling
Processes -Managers Experience -Accident
History
Scoring Model to estimate a plants risk for a
toxic spill.
5 Scoring Models
- A type of Inference Tree which assesses a
non-observable variable through other data which
can be observed or measured - (e.g. the probability of some negative event or
the effectiveness of some complex system). - Purpose Replace Individual Judgment with a more
reliable method. - Risk Index w(1)RF(1) ... w(n)RF(n)
6Risk Factors
7Risk Factors
8(No Transcript)
9Contract to Build a Scoring Model as alternative
to IBC Height Area Table 503.
- Frank Noonan reporting to Kate Dargan and Dave
Collins - Phase 1 Work with the BFP Features Study Group
as SMEs to build a prototype model. - Phase 2 Continuing with BFP Study Group open
model to a larger group of building safety
professionals to review and fine tune the model. - Timeframe 3/8/07 2/28/08
10SSM development for IBC
- 1. Establish SMEs and communication framework.
- 2. Define risk metric for building safety
performance. - 3. Define set of risk factors (and scales) for
risk assessment, - (e.g. occupancy classification, height,
area, full menu of active and passive risk
mitigation measures, expected emergency
response). - 4. Define relative importance of each risk
factor. - 5. Calibrate Scoring Model for Acceptable Risk on
Building Safety Performance.
11Establish SMEs and communication framework.
- SMEs Study Group Facilitator Frank Noonan
- MyWPI is internet forum
- Need name and email address of each SME
- Site Name BFP Features Study Group
- Discussion/ Voting/ Finding Consensus
122. Define risk metric for building safety
performance
- Narrative describing Building Safety (or risk
to building safety) - Sets transition for defining risk factors.
- Process 1st draft today (8/3/07) post for
revisions complete by 8/24/07. - Risk Metric w(1)RF(1)w(n)RF(n)
- Scale 0,10
- GAR GGGGGAAARRRRR
-
13Risk Metric Narrative
- Building Safety is defined as the aggregate
effectiveness of the mitigation features ((Active
and Passive and Emergency Response) in a building
that are provided to protect the structure,
occupants, emergency responders, and property
from losses associated with anticipated hazards
primarily due to fire exposure and subsequent
collapse. - Building Safety Success can be defined as
meeting the goals for the reduction - of life and property loss that are
acceptable and economically supportable. This - is the core concept of acceptable risk.
Acceptable building safety risk is that level of
anticipated loss that each entity impacted can
accept if a hazardous event occurs. It is based
on the probabilities that the various mitigation
strategies will perform as intended and it can be
measured as a quantitative value, a qualitative
value, or both. - Identify and analyze a buildings hazards and the
potential mitigations of those - hazards that positively impact building
safety and also considers their probability for
successful performance
143. Define set of risk factors (and scales)
for risk assessment
- Set of RF complete, clear, avoid redundancy.
- Pursue Hierarchical Structure ( i.e. inference
tree). - See example on next slide.
- Process 1st draft today (8/3/07) post for
revisions complete by 9/5/07. - Each factor requires a narrative definition and a
scale. - Whenever possible use objective scale, defining
best and worst. - 0,1 factors are allowed.
- Risk factor constraints are allowed as necessary
conditions for G or R.
15 Example from U.S. Navy Vessel Refueling
Decision
- Major categories
- Task Difficulty
- Environmental
- Equipment Readiness
- Manpower Readiness
16Risk Factors
- 1. Exiting
- 2. Compartmentation
- 3. Smoke Management
- 4. Automatic Sprinklering
- 5. Fire-Resistive Construction
- 6. Structural Integrity
- 7. Better Inspection and Maintenance Compliance
- 8. Emergency Response
- 9. Occupancy Type
174. 4. Define relative importance of each
risk factor.
- Method of Pair-wise Comparisons
- Rank order the set and use least important as
anchor to elicit relative importance repeat
using most important as anchor. - Make effort to exploit the hierarchy.
- Process
- Voting Average and post results
- Start voting on 9/07/07 post Round 1 results by
9/18/07 post Round 2 results by 9/28/07. - Eliminate factors if weight is less than 1 and
more than 15 factors.
18 5. Calibrate Scoring Model for Acceptable
Risk on Building Safety Performance.
- Create a set of Bldg Design/Operating Scenarios
where bldg safety performance is on margin with
respect to Acceptable Risk. - Each scenario has an SME creator who provides a
narrative and set of risk factor scores. - Once a scenario is created other SMEs may weigh
in on scores and make a GAR vote scenario is
eliminated if simple majority vote it as G or R.
(cont.)
195. Calibrate Scoring Model for Acceptable
Risk on Building Safety Performance.
- Need Scenarios My worry is with too few rather
than too many. - Each scenario produces a risk index score and
their range defines the Amber range in the GAR
scale. - Process Start 10/1/07 complete by 11/1/07.19
20Review Fine Tune Prototype Model
- In Jan/Feb 08, post the BFP Features Study Group
prototype model for input from larger group of
building safety professionals. - Revisions to
- Constraints on risk factors
- Relative weights of risk factors
- Ruling out any scenarios on acceptable risk margin