8.3.1 IiDENTlIFICATION
OF POTENTIAL CONSEQUENCES
BASED ON
HAZARDS
B a s e d o n T O a cci de n t s c e n a r i o s,
aoanaolysis was performed. The scenarios, which
are presented in certain hazardous materials that could serve as "triggers" for these
these analyses wweerree compared with 0 base risk ossessmenl ot the results oft the risk onolysis, augmented by other aspects oft ItIhe research and 10 thorough review, indicate which classes
these accident scenarios, each oft the tToour routes in Wayne Countly were oanaoltyzed.
analyses with base risk assessment of the some 10 scenartios
of hazardous materials shout|d be restricted ftfor each of the tToour routes, and the potential for risk to human lifte, the environment, property and
Table 6.
Accident Scenarios
Boiling LiquidEXxpunding Vapor Explosion
8 . 4 RO U T I NG MET HODOLOGY F O R S EL E C T E D ROUT E S
the Ttoour Wayne County routes.
The next step
was to
estimate the number of hazardous materials accidents that might occur on the route segments being evaluated.
The
two
discriminating Ffaacttors were route length and hoazmoat carriert accident rate differences.
For oil the reute
segments analyzed,
restricting (prohibiting) Class 3 (Flammable Liquids) hazardous materials shipments higher frequency of accidents involving Class 3 hazmat carriers outweighs the higher consequences of the other classes and divisions of hazardous materials. It transportation of previously
would result in the biggest risk reduction. This is because Class 3 materials represent more than halt ofi the hoazmoat shipments documented in this study. Although higher TtToottaolliity rates are protjtected for other classes of hazardous materials, the higher frequency of accidents involving Class hozmot
ot previously restrticted hazardous materials was allowed
on Wayne County routes, a safeguard could be added by requiring that the hoazmoat shipment motor carriers travel with an escort vehicle or vehicles. iIn addition to esco'rting, another precaution could be added to close the particular route segment being used ftor 0a short, controlled distance aond/or ftor a specified period of time.