Risk Analysis

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Risk Analysis

• For ES-317Y and ES 497 2002 Plant
  Design Project at UWO
• By R.A. Hawrelak, P.Eng. - Lecturer
  Dept of Chem Biochem Engg
  Dow Chemical 1960 to 1993

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What is Risk Analysis?

• A risk analysis is any study that identifies
  hazardous concerns.
• There are many types of risk analyses (PHA,
  HAZOP, Dow Fire and Explosion Index, QRA).
• Two basic methodologies. One is
  a Deterministic Method and the other is a
  Probabilistic Method.

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Deterministic Methods

• How far to LEL?
• How far to second degree burns?
• How far to 1 psig Overpressure in a VCE (building
  damage)?
• How far to ERPG2 - a toxic concentration endpoint
  for a dispersion.

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Probabilistic Method

• Quantitative Risk Analysis (QRA)
• What is probability of reaching the LEL at a
  certain distance?
• What is probability of receiving second degree
  burns?
• What is probability of receiving 1 psig
  Overpressure from a VCE?

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Netherlands Opts For QRA

• Detailed QRA legislated by law. Permits reqd for
  all plants.
• Individual Risk negligible at 1E-08 chance of
  fatality per year.
• Societal Risk required to meet specified
  Guidelines.
• All companies use SAFETI, a huge, complex
  computer model.

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Dutch Individual Risk
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Dutch Societal Risk
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Great Britain Opts For QRA

• Detailed QRA required if HSE deems the plant
  exceeds certain planning criteria.
• QRA can be performed by HSE or any recognized
  risk company.
• HSE has proposed 1E-06 chance of fatality as a
  level of risk that would be broadly acceptable to
  members of the public.

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US EPA Opts For A Deterministic Risk Method

• Risk Management Plan (RMP) became law on 20 June,
  1996.
• Worst Case Scenario and Alternative Scenario for
  each toxic chemical.
• Only one flammable scenario - Worst Case and
  Alternative, the one that impacts on the public
  to the greatest extent.

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U.S. RMP Computer Program

• RMP Manual available with 27 examples or .
• Free download of RMP computer program at
  http//www.epa.gov/ceppo/tools/rmp-comp/rmp-comp.h
  tml
• Download it on to your hard disc.
• Its very simple to use.
• If you dont know your storage quantity yet, run
  the threshold quantity to see how big a problem
  you may have. You may decide to store less.

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1994 - Canada Opts For Guidelines

• Major Industrial Accidents Council of Canada
  (MIACC).
• MIACC modifies Dutch Guide To Hazardous
  Industrial Activities.
• A two point probabilistic method using Individual
  Risk as negligible at 1E-06.
• Dow Chemical does not accept the two point
  concept because it is fundamentally flawed (RAH
  MIACC rep for Dow).

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MIACC Publications

• Lists of Hazardous Substances - 1994
• Hazardous Substances Risk Assessment a
  Mini-Guide for Municipalities and Industry.
• Risk Assessment Guidelines for Municipalities and
  Industries - An Initial Screening Tool.

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New Canadian Draft Regulation

• Ottawa, August 20, 2002.
• Industrial Facilities that handle dangerous
  substances will be required to develop accident
  prevention plans.
• http//www.ec.gc.ca/press/2002/020820_n_e.htm
• Environmental Emergency (E2) Regulations under
  Canadian Environmental Protection Act, 1999 (CEPA
  1999)
• Targets an initial list of 174 substances.

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What Info Included in E2 Plan?

• Senior management commitment.
• Types of on-site and off-site emergencies.
• A description of individual roles
  responsibilities.
• Contact lists.
• Training logs.
• A means for ensuring the plan is current,
  comprehensive and effective.

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E2 Implementation

• 1500 facilities expected to comply with the
  proposed regulation.
• Must develop, implement and test an emergency
  plan within 1 year of the regulation coming into
  effect.
• Regulation is expected to be in place early in
  2003.

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E2 Submissions

• E2 plans will not be submitted.
• Two declarations must be submitted.
• (1) A declaration that a E2 plan has been
  prepared and is being implemented.
• (2) A declaration of implementation indicating
  that implementation of the E2 plan has been
  completed.

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Info in Declarations

• Facility data.
• An indication of whether or not environmental
  emergency prevention, preparedness, response and
  recovery measures are identified in the plan.
• An indication that information from previous
  environmental emergencies has been incorporated
  into the plan.

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Key References Used in E2

• See Appendix 3 in Draft Regulation.
• Quebec Guide CRAIM, Risk management for Major
  Industrial Accidents intended for municipalities
  and Industry (Based on U.S. RMP).
• Hazardous Substances Risk Assessment a
  Mini-Guide for Municipalities and Industry.
  (Flawed methodology RAH).

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E-2 Concerns

• Need to Question the threshold quantity in List
  of Substances.
• Concern that smaller quantities may impact on the
  public in areas where the public is too close to
  the chemical facility.
• Concern regarding lack of a permit to operate.
  The EPA gives a permit to operate based on the
  RMP program.

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RMP Concerns

• RMP stresses ERPG2 end points for toxic
  chemicals. This low concentration results in long
  impact distance for any given dispersion.
• RMP requires ER planning over a large area which
  is difficult to plan and manage.
• RMP does not identify acute hazardous areas
  closer to the source. These area are extremely
  vulnerable in short time frames.
• Use of alternate dispersion models must be
  qualified against known data points.
• RMP focus is on storage. More hazardous areas
  such as reactors are not included (Flixborough).

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End of Presentation

• Good luck on your project.
• Questions can be asked via e-mail at
  richardhaw_at_sympatico.ca