This test method was prepared as a guide for evaluating the application of polymeric coatings to the internal surfaces of metallic tubular goods used in the oil and gas industry. It is not intended as a means of predicting the service life or service performance of these coatings. This test method is based on the current technology and experience of the petroleum production industry. NACE Standard Test Method TM0384 addresses holiday detection of internal tubular coatings of less than 10 mils (0.25 mm) day film thickness.

This NACE test method was prepared by Task Group T-1 G-9 of Unit Committee T-1 G on Protective Coatings, Elastomers, and other Nonmetallic Materials for Oil Field Use and is issued under the auspices of NACE Group Committee T-1 on Corrosion Control in Petroleum Production, which is composed of representatives from industry including consumers, producers, and interested individuals.

1.1 This NACE standard provides a nondestructive test method for the detection of holidays in a nonconductive coating film that has been applied to the inner wall (bore) of oil field tubular goods. Test apparatus for conducting this test are described along with the recommended procedure for conducting the test. Methods of reporting the test data are described.

1.2 The test method applies to coatings that have a dry film thickness of 10 to 30 mils (0.25 to 0.70 mm) and have not been in service or previously tested for holidays with a salt solution. With holiday testing coatings which have been in service or previously tested for holidays with a salt solution, there is a possibility of misleading results arising from surface contamination or salt bridging. The coating surface shall be free of materials that give added electrical insulation or will mechanically damage the coating during the test.

1.3 For the purposes of this standard, a "holiday" is defined as an area in an applied nonconductive coating which exhibits electrical conductivity when exposed to a known impressed voltage.

1.4 The voltage range for holiday detection is 100 to 300 volts (DC) per mil of dry film thickness. The test voltage is determined by the type of probe, the maximum specified dry film thickness, applicable coating application, and the customer. The voltage shall be measured between the probe and the pipe. Historical Document 1989