Venting, mitigation measures

Flare stacks that safely bum organic material released into vent headers are an example of a prerelease mitigation measure. The flare destroys the hazardous organic material before it reaches the environment. A dike around a storage tank is an example of a postrelease mitigation measure. The dike contains the release in a small area, reducing the total evaporation rate from the spill and so reducing the impact of the release. 

Radon- A naturally-occurring, heavier than air, radioactive gas common in many parts of the country. Radon gas exposure is associated with lung cancer. Mitigation measures may involve crawl space and basement venting and various forms of vapor barriers. 

The purpose of this question was to find out whether any additional iodine mitigation measures have been planned or already implemented other than using additives in the spray and containment sump water and using controlled containment venting with a filter. Other than these measures, if already implemented, there are no other mitigation measures reported by the participating organizations. 

Plant name Filters (PF=prefilter, AF=absolute filter, ACF=active carbon filter, D = demister) Containment venting filters Passive iodine removal Iodine mitigation measures implemented/ planned Measurement of airborne iodine (gaseous and particulate form) activity ... 

Plant Name Containment Venting Filters Passive Iodine Removal Iodine Mitigation measures Measurement of airborne iodine in containment Measurement of controlled iodine (gaseous release into environment Other AM measures to mitigate (1) airborne iodine in containment... 

Because there are no reasonable methods for mitigating risk following the occurrence of a BLEVE, all practical measures should be taken to prevent the causes of a BLEVE. This could include fixed water-spray systems over process vessels containing flammable liquids or which could be exposed to flammable-liquid fire, ensuring that relief devices do not direct vented flammable vapors onto the container, systems for diverting spilled flammable liquid to locations that would not expose process vessels, and pubhc-address systems to warn persons to evacuate locations where loss of process control could lead to a BLEVE [14]. 

No containment venting filters, no passive iodine removal, no controlled iodine release into environment, no other AM measures to mitigate airborne iodine activity in containment... 

By implementing containment venting and hydrogen control measures, it may be possible to delay or prevent gross structural failure of the containment. This in turn would provide some additional time to mitigate the accident or to reduce the off-site-consequences of the accident compared to those produced by gross containment failure. 

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