are given in Table VIII. A later report on this test (Drisko, I968) rated 

 the saran to be in good-fair condition after 5 years of exposure. One 

 source (Drisko and Brouillette, I965) reports that saran has given excel- 

 lent protection to steel panels exposed in shallow seawater for h years. 



A 6.5-niil coating built up with alternate coats of orange and white 

 Formula 113/^0 saran applied over sand-blasted steel was reported to 

 be giving good protection after 10 1/2 years of exposure in seawater 

 (Alumbaugh and Brouillette, I966). Saran applied over flame-sprayed 

 zinc in the same tests was reported to be providing complete protection 

 to the steel from rusting after 10 1/2 years. See Figures lib and lie. 



(6) Asphalt Emulsion, Mica-Filled . Tests of a mica-filled 

 asphalt emulsion showed it to be inadequate in two corrosion zones after 

 2 1/2 years of testing in seawater. This coating performed poorly in 

 the upper tidal zone and afforded practically no protection in the abra- 

 sion zone at the end of 2 1/2 years according to the evaluation ratings 

 (Altmibaugh, I962). 



(T) Coal-Tar Epoxy . Coal-tar epoxies are a blend of coal tar 

 and epoxy resins. Although coal-tar epoxies have been rather extensively 

 used as a coating on marine structures in the past few years, very little 

 actual test data has been found concerning it. Table VIII gives the rating 

 "good-fair" for coal-tar epoxy over an epoxy primer tested on a mooring 

 buoy for over 2 years (Drisko, I965). A later report (Alumbaugh, 196^+) 

 on this test also rates the coating "good-fair" after 5 years of service. 



Two coats of catalyzed coal-tar epoxy primer and 1 coat of aluminum- 

 filled catalyzed coal-tar epoxy topcoat giving a total thickness of 15 

 mils were applied to steel and tested in shallow seawater. This coating 

 is reported to have given excellent protection to the steel for 3 years 

 (Drisko and Brouillette, I965). 



Recent test data (Alumbaugh and Brouillette, I966) shows coal-tar 

 epoxies to hold considerable promise for protecting steel in seawater. 

 A 12-mil coating did not fail until between 7 and 9 years of exposure. 

 Thicker coatings (up to 2^.5 mils) being tested are expected to be rated 

 among the better coatings for protecting steel piling. See Figure 11a. 

 Figure 12 shows that coal-tar epoxy coatings were also among the better 

 coatings in withstanding sand abrasion in the surf zone. 



(8) Epoxy . An epoxy coating has recently been developed which 

 can be applied and cured on surfaces, under water, or dry. Based on short- 

 term tests (Drisko and Brouillette, 1965),this coating is quite versatile. 

 The coating is prepared for use by mixing two components and can be applied 

 to surfaces under water or to dry surfaces by workmen using rubber gloves. 

 Thicknesses exceeding 1/8 inch have been recommended for the coating. 



Tests of six months' duration were made to determine the adhesive 

 strength of epoxy coatings to bare steel and to other types of coatings. 

 The findings and conclusions given in a report (Drisko, et al, 196U) 

 resulting from this test are as follows: 



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