During late 2004 and early 2005, the United States Coast Guard (USCG) and the U.S. Minerals Management Services’ (MMS) Ohmsett—The National Oil Spill Response Test Facility collaborated in an effort to develop a standard protocol for testing static oil skimmers. The goal was to develop a repeatable generic skimmer test procedure that substantively met ASTM Standard F631, Standard Guide for Collecting Skimmer Performance Data in Controlled Environments, while incorporating the formula for computing Effective Daily Recovery Capacity (EDRC) found in 33 CFR Part 154, Appendix C, Section 6.3, and 33 CFR Part 155, Appendix B, Section 6.3. The USCG uses EDRC as one of many tools to rate and regulate the oil spill response capability of potential responsible parties and oil spill response organizations. To this end a draft protocol was developed (Ohmsett, 2004).
The draft protocol was used for the first time at the Ohmsett Facility during a contracted series of tests aimed at comparing seven different skimmers supplied by five manufacturers. Testing was conducted in the Ohmsett main test tank. Six condition sets formed the test matrix as derived from the targeted variables of oil type (ASTM Type I and Type III), oil slick thickness (10 mm and 25 mm), and water surface condition (calm vs. waves).
Results indicate that the draft test protocol produced reliable, reproducible data that can be used to compare skimmer performance for a given set of test conditions as long as ambient variables such as temperature and wind effect were constant. However, as would be expected, no correlation or trends were observable for tests conducted at different ambient conditions.
Based upon the data and experience of this first time use of the draft protocol, a number of observations and suggestions were forwarded by the authors to improve the procedure. It is hoped that further use, critical review, and adaptation of the protocol will allow it to evolve into an industry standard to compare skimmer performance. Additionally, the more comprehensive a protocol such as this may become, the more it may assist regulators in classifying response organizations as to their oil recovery capacity.
Development of skimmer testing protocol based on ASTM standards by minerals management service and U.S. coast guard at Ohmsett facility