Hazard domino effects

Simpler plants are friendlier than complex plants because they provide fewer opportunities for error and because they contain less equipment that can cause problems. Often, the reason for complexity in a plant is the need to add equipment and automation to control the hazards. Simplification reduces the opportunities for errors and misoperation. For example, (1) piping systems can be designed to minimize leaks or failures, (2) transfer systems can be designed to minimize the potential for leaks, (3) process steps and units can be separated to prevent the domino effect, (4) fail-safe valves can be added, (5) equipment and controls can be placed in a logical order, and (6) the status of the process can be made visible and clear at all times. 

Domino effect An incident which starts in one piece of equipment and affects other nearby items, such as vessels containing hazardous materials, by thermal blast or fragment impact. This can lead to escalation of consequences or frequency of occurrence. This is also known as a knock-on effect. 

Preliminary hazard review is intended to evaluate major hazards at the early stages of technology development and/or proposal development and project planning. Inherently safer design, high risk process elimination, appropriate safeguards and the need for further studies are identified at this stage. This would help the project team to understand major on- and off-site risks and the kind of domino effects from events, which may impact the environment and corporate reputation. 

Cozzani V, Antonioni G, Spadoni G, et al. 2005. The assessment of risk caused by domino effect in quantitative area risk analysis. Journal of Hazardous Materials, 127(1-3), 14—30. 

Darbra, R.M, Adriana Palados, Joaquim Casal. 2010. Domino effect in chemical accidents Main features and accident sequences. Journal of Hazardous Materials, 183(1), 565-573. 

Among the natural phenomena capable to determine serious hazards to industrial plants, earthquakes should be taken into account especially because they are capjable to generate multiple sources of releasing of dangerous substances and domino effects within the same plant, determining the complete destruction of the site. The analysis of p>ast accidents induced by earthquakes has shown the high vulnerability of some typical industrial compxjnents and the severity of the consequences. 

Because of their random behavior, projectiles from BLEVEs are one of the most difficult hazards to quantify (Birk, 1996). The fragments thrown by the explosion have a restricted and directional action, but with a larger radius of destructive effects than the pressure wave and the thermal effects of the fireball. These fragments can cause a domino effect if they destroy other tanks or equipment. The velocity required by a fragment to penetrate another similar tank ranges from 4 to 12 m s , and the maximum velocity that can be reached by the fragments in a BLEVE explosion—a function of the conditions at which the explosion occurs, the volume of vapor initially contained in the vessel, and the shape of the vessel— ranges from 150 to 200 m s. ... 

An overriding principle in the storage of chemicals is that they should not be adversely affected by other adjacent substances or operations. An HSE Guidance Note gives suitable information on this topic. The COMAH Regulations also require consideration to be given to the quantities of hazardous materials that are stored at chemical sites located near to a COMAH site because of the possible domino effect of an incident at one company affecting adjacent companies. 

As mentioned, the directive is totally revised and many new areas are now covered, to such an extent that it forces member states to develop and investigate their own policies to be able to properly implement the directive. To mention a few topics new in this directive domino effects, emergency plans, land use planning, information to the public, prohibition of use of the installation, environmental hazards. The scope has been broadened major hazard policy and safety management systems are now included, the safety report is now used as a tool via which companies have to demonstrate that they are safe, there are time constraints to which companies and regulators have to adhere, and regulators have been given specific enforcement roles with respect to assessment and inspections. 

None of the above methods consider flame impingement. In assessing rite potential for domino effects on adjacent hazardous vessels, the dimensions of the jet flame can be used to determine whether flame impingement is likely. If so, heat transfer effects will exceed the radiative fraction noted above, and a higher heat fraction could be transferred to the impinged vessel. 

Reniers, G. (2010). An external domino effects investment approach to improve cross-plant safety within chemical clusters. Journal of Hazardous Materials 117(1-3), 167-174. 

Domino effects Short-term hazard and risk assessment Time-dependent risk Triggering... 

The prediction of fixigment effects is important, as many deaths and domino damage effects are attributable to fragments. The method of Baker et al. (1983) can be used, but specific worit on BLEVE firagmentation hazards has been done by the Association of American Railroads (AAR) (1972,1973) and by Holden and Reeves (1985). The AAR reports that of 113 major failures of horizontal cylindrical tanks in fire situations, about 80% resulted in projected fragments. 

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