H3 on Subs

[DREHA@ccmail.ceco.com]

     To those unfamiliar, Naval reactor plants are very tight; near zero 
     leakage primary coolant systems. As a result, there is very little 
     exposure to primary coolant at all, with one exception.
     
     The duty "ELT" draws primary coolant samples daily, and purges a 
     decent volume of coolant when getting a depressurized sample. This 
     poses a potential risk for tritium exposure. Several factors come in 
     to play to mitigate the risk.
     
     As I remember, on S5W boats, there was a ventilation supply duct that 
     practically blew on my face while drawing the samples. I don't know if 
     this was an accident in design, probably not. The ELT also wears a 
     faceshield, rubber gloves, a rubber apron, and plastic arm-sleeves 
     when drawing the samples. All purged coolant was hard-piped directly 
     to sealed retention tanks that were isolated when draing was not 
     actively in-progress.
     
     As far as tritium vapor, the engineering spaces on a sub are quite 
     humid, with several "spot coolers" that are fed with chilled water in 
     cooling coils. From a real-life tritium excursion we experienced while 
     I was staff at a prototype, I know that the spot coolers are HIGHLY 
     efficient at removing tritiated water vapor in the air.
     
     The condensation from the coolers went to the bilges. The bilges are 
     frequently pumped overboard, and usually had some amount of oil on the 
     surface, which acts to minimize evaporation.
     
     In short, I don't know what the tritium levels were in the coolant, 
     but (unscientifically) it looks like the risks of exposure were quite 
     low. On the surface, Navy RadCon and RadChem looks quite simplistic, 
     but few realize the amount of work that went into the development of 
     the program. After 4 yrs in commercial power reactors, I appreciate 
     the value of a non-nonsense, no bells and whistles, back to basics 
     approach to field RadCon.
     
     Disclaimer: my opinions are mine and mine only.
     
     P.S.  Does anyone remember the original issue?
     
     
     
     Best wishes;
     
     
     H.Anagnostopoulos
     DREHA@ccmail.ceco.com