Water film thickness effects from automatic fire sprinklers

The study of water film thickness effects from automatic fire sprinklers is necessary because DOE recently mandated the use of automatic fire protection for the Fuel Fabrication Facility at the Savannah River Site (SRS). The primary nuclear criticality safety concern with overhead automatic fire sprinkler systems is the coating effect (film) as it spreads over the fissile material surface. This would affect nuclear criticality safety because moderating materials (water, plastic, and paper) are currently limited in arrays of fuel components to ensure subcriticality. Hence, before a sprinkler system can be authorized, it is necessary to evaluate the reactivity effects of water sprinklers on arrays of fuel components. This in turn requires a determination of the amount and distribution of water deposited on the fissile arrays by the sprinklers. There has been limited research dealing with water film formation from fire protection systems, thus a study has begun to characterize these water films. This paper discusses the development of methods and experimental procedure, preliminary results, and the future program. 2 refs.