Except the band-type guard, the thickness of the guard that is made of rolled steel shall base on the highest using peripheral velocity of the grinding wheel, the thickness and the diameter of that wheel to be the value no less than in Attachment table 27.Based on the type of material, the thickness of the guard that is made of cast iron, malleable iron or cast steel shall be over the thickness get from the preceding paragraph multiplied by the coefficient in Attachment table 28.Attachment table 27.pdfAttachment table 27.docAttachment table 28.pdfAttachment table 28.doc