Comments on "Experience with the merry-go-round test" [with reply]

For original paper by S.M. Gubanski see ibid., vol.25, p.331-40 (1990). The commenter raises the question of how long silicone rubber can preserve its hydrophobicity despite pollution, in the context of the interpretation in the above-titled paper of merry-go-round (MGR) test results. The commenter also raises the issue of the validity of the MGR test in relation to polymers containing each different quantities of filler. Gubanski discusses the first issue in some detail, and the second briefly. Gubanski concludes that the MGR test leads, in many cases, to contradictory results and that more work has to be done before it could be applied for material assessment for HV outdoor insulation.<>