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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 Eng’g Dow Chemical – 1960 to 1993. What is 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 Eng’g Dow Chemical – 1960 to 1993
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.
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.
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?
Netherlands Opts For QRA • Detailed QRA legislated by law. Permits req’d 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.
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.
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.
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.html • Download it on to your hard disc. • It’s very simple to use. • If you don’t know your storage quantity yet, run the threshold quantity to see how big a problem you may have. You may decide to store less.
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).
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.
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.
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.
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.
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.
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.
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).
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.
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).
End of Presentation • Good luck on your project. • Questions can be asked via e-mail at richardhaw@sympatico.ca