Unclassified 



Security Classification 



DOCUMENT CONTROL DATA - R&D 



ty ctaaailication o/ title, body ol abstract and indexing annotation must be entered when the 



1. ORIGINATING ACTIVITY (Corpon 



U. S. Naval Civil Engineering Laboratory 

 Port Hueneme, California 93041 



2a. REPORT SECURI TY CLASSIFIC* 



Unclassified 



2b GROUP 



3 REPORT TITLE 



Deep-Ocean Biodeterioration of Materials — Part IV. One Year at 6,800 Feet 



4. DESCRIPTIVE NOTES (Type ol report and inclusive dates) 



March 1964 -March 1966 



5 AUTHORfSJ (Last name, lirst name, initial) 



Muraoka, James S. 



6 REPO RT DATE 



June 1966 



CONTRACT OR GRANT NO. 



b. PROJECT NO. 



Y-ROn-01-01-042 



7a- TOTAL NO. OF PACES 



60 



7b. NO. OF REFS 



12 



9a. ORIGINATOR'S REPORT NUMBERfSJ 



TR-456 



10 AVAILABILITY/LIMITATION NOTICES 



Distribution of this document is unlimited. 



It. SUPPLEMENTARY NOTES 



12. SPONSORING MILITARY ACTIVITY 



Naval Facilities Engineering Command 



13 ABSTRACT 



As Part IV of a series of reports on the biological deterioration of materials in the 

 deep ocean, this report covers the data obtained after exposing metallic and nonmetallic 

 specimens for 13 months on the floor of the Pacific Ocean at a depth of 6,800 feet (Test 

 Site I), The specimens were attached to a Submersible Test Unit that was retrieved in 

 February 1965. Preliminary examination of the specimens was made aboard ship, and the 

 final examination, tests, and analyses were performed at the Naval Civil Engineering 

 Laboratory. 



On recovery, most of the plastic materials and all of the rope specimens were covered 

 with bacterial slime. Cotton and manila rope specimens were severely deteriorated by marine 

 microorganisms. Wooden test panels, plastics, and Manila ropes were attacked by molluscan 

 borers. Gloss, metals, natural and butyl rubber, and certain plastic materials were not 

 adversely affected. 



The results of breaking-strength tests on ropes, weight loss measurements of wood panels, 

 moisture absorption tests on plastics, and insulation resistance and voltage breakdown tests 

 on electrical insulating materials are presented. 



DD 



1473 



0101-807-6800 



Unclassified 



Security Classification 



