o Personnel 50 to 100 feet away from the work site must wear 

 protective eyeware, gloves, disposal coveralls, and NIOSH-approved, 

 full-face, organic vapor respirators; and 



o Shipyard Safety Officer and Industrial Hygienist shall be contacted 

 for specific personnel precautions when spray application is 

 planned. 



The applicator exposure study conducted by M&T Chemicals Inc. 

 (Envirosphere, 1986) at the Curacao Drydock Company found that the actual 

 level of worker protection was found to vary because of work practices of 

 the painters and their helpers. Principal difficulties were encountered 

 in working in hot humid environments while completely sealed in air im- 

 pervious suits without the addition of circulated air except for that 

 provided directly for breathing. Other results derived from this study 

 are: (1) pre-employment body burdens for organotin was found to be between 

 4 and 5 parts per billion, (2) air hoods are effective respiratory protec- 

 tion for keeping painters exposure to organotin below the OSHA Permitted 

 Exposure Level (PEL) , (3) dermal contact is more significant than inhala- 

 tion as the route of worker exposure, and (4) worker urinary organotin 

 levels quickly returned to pre-exposure levels after cessation of exposure 

 to the organotin paints. These results were determined during the applica- 

 tion of paint containing 3.2% tributyltin methacrylate, 1.3% tributyltin 

 oxide, and 1.7% triphenyltin fluoride using airless spray equipment. 



Application by brush is the preferred method for the small boat owner 

 because of low capitol investment and low level of skill required for a 

 satisfactory job. Some of the paint remains in the container, between 

 2.5% and 4.5% by weight according to US Navy Studies and some remains in 

 brushes and cleaning rags. These are potential sources of TBT to the 

 environment, if not properly disposed. 



3.6.2 Recommended Paint Removal Practices 



Various removal practices provide different risks of introducing TBT into 

 the environment. Each practice offers different control possibilities. 

 Removal of the paint film or portions of it may occur intentionally or 

 unintentionally during wash down with a high pressure hose prior to sea- 

 sonal storage or other work on the hull. US Navy studies have found that 

 as much as 60 mg of TBT per square centimeter of hull surface can be 

 washed into the environment with high pressure wash down of the paint 

 (U.S. NAVSEA, 1984) . The British Government and the Royal Yachting Asso- 

 ciation have also found that the use of high pressure wash down to be a 

 source of TBT to the environment and have specifically recommended that 

 the pressure of the power wash nozzles be monitored and adjusted to 

 minimize the removal of the paint film during cleaning operations. Paint 

 manufacturers in the U.S. recommend the use of high pressure wash down of 

 antifouling paints as soon as the vessel is out of the water as a means of 

 keeping the bioactivity of the paint as high as possible. 



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