Risk assessments

The storage and usage of hazardous materials are an inseparable part of many factories, business and infrastructures. In the case of a mishap, such as a leakage, these materials can cause a hazardous materials event and have devastating results, such as dispersion of a toxic cloud, a fire pool, explosion and more. These mishaps can be due to easily controlled procedures or uncontrolled incidents such as mechanical failures and force majeure. To prevent a dangerous event two regulations were set. A "Toxic Permit" which precedes any usage of hazardous materials (import, dispersion and production) except specific cases as determined by the hazardous materials regulations, classification and exemption and a "hazard survey" which often is a preliminary condition for receiving or renewing a "Toxic Permit". In order to receive a "Toxic Permit" all the hazardous materials used have to be reported as well as additional data requested. Usually no extra action, in addition to what is in the permit request form, is needed. Despite this, the potential effect of hazardous materials at the site, according to its storage, should be checked. This can prevent a rejection based on unacceptable risks. The "hazard survey" is a survey of the characterizations of the hazardous materials stored (toxicity, volatility, inflammability and etc.). According to these characterizations, amount and storage of materials the potential effect on the environment at different scenarios is tested by accepted mathematical models and equations. Based on these estimations the distance from the storehouse, the protection facilities and emergency procedures needed to reduce the affect on the environment are determined. The risk factor of a hazardous materials event is the damage potency on the environment multiplied by the probability of an incident. In certain cases, this is multiplied by the population at the range of the event to ascertain the number of potential casualties. Therefore, a "probability-population survey" (estimates the probability of an event and the size of population at risk) is done, at times, in addition to a "hazard survey" to determine the risk of a certain facility and if the risk involved is accepted or additional precautions and/or changes in amount/composition of the materials are needed.