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mind your safetyBy Dave SmithHard hats and jerkingknees... againMy column regarding foam-insert hard hatsseems to have created a bit of controversy(EBMag Dec/January 2009/10, “Heads upand hats off with foam inserts”). I received anemail from an individual who was concerned mycolumn may be misconstrued. He writes:I am very worried that your article will [push]the electrical community to [a] knee-jerkreaction, and many workers—as you say—[may] exercise the right to refuse unsafe work.In that column, I advise that when you arewearing a foam-insert hard hat inside theLimited Approach Boundary or Flash ProtectionBoundary, you should ensure that it has been arcflash or flame-resistant tested. Since there ispresently no standard for testing these materials,this cannot be done.A sidebar to the article referenced a video clipof a foam-insert igniting and melting the plastichard hat. The result was a hard hat that drippedto the floor around the test mannequin.Critics of the video have focused on the factthat it showed a 15-calorie test, claiming it isinvalid because, with 15-cal exposure, you wouldbe required to wear Category 3 FR clothing.(Which, by the way, is absolutely correct if youknew you were being exposed to 15 calories ofincident energy. If you identify the incidentenergy as 15 cal, then you definitely need to bein a Category 3 suit with a minimum rating of25 cal, plus other PPE listed in Table 5, page 48of CSA Z462, “Workplace Electrical Safety”.)But if you thought you were being exposed toa Category 0 HRC (based on the tasks in Table4, page 43, or incident energy below 1.2 cal, asstated on an equipment label), then the presentindustrial standard is to only wear a hard hat andsafety glasses. If that hard hat was of the foaminsert variety, you would have a risk.The first step prior to doing any electricalwork is to perform a Hazard/Risk Evaluation (pg22, 4.1.7.6 and pg 99, Annex F). You need tounderstand that, when the incident energy at 18in. from the source of the energy is determinedIdeal_EB_April10.indd 110 • April 2010 • www.EBMag.com3/17/10 1:30:37 PM