UL 1581 Swellling and Blistering in water

1043.1 The specifications for this test are located in Swelling and Blistering when Immersed in Fluid, in the Standard for Wire and Cable Test Methods, UL 2556.
1043.1 revised July 28, 2008
1043.2 Deleted July 28, 2008

1043.3 The cord does not comply where there is any evidence of blistering. Where there is no blistering, the maximum and minimum diameters of the cord are to be measured immediately at each of the five marked points. The sum of these ten measurements is to be divided by 10 and recorded as D, the average diameter of the cord after immersion. The cord does not comply where the increase I in average
diameter (swelling) calculated as follows exceeds 20.0 percent.

I = 100(D − d)/d

1044 – 1059 Reserved for Future Use

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