Our previous discussion on modifications to the basic 1220 formula dealt only with results from our in-house testing. Since that time, other companies using different test machines and criteria have run comparative tests with the basic 1220 coating and the modified 1220C coating and have obtained increased performance similar to our in-house tests.

Table III summarizes the results using three different test machines including our pin and vee groove machine. This table illustrates that all three procedures show similar improvement in performance even though they differ greatly in specimen configuration and test conditions.