In the EDITORIAL by this title, published in the May 28 issue (224:1287, 1973), this misstatement occurred in the second paragraph: "... nurses and physicians wear nonconductive shoes, and hospital floors are made of nonconductive material." Technical requirements for fire and explosion safety as related to electrostatic charges are, in fact, that the shoes and floor be conductive.
Furthermore, the last paragraph of the editorial refers to "polarity" as a problem in operating room electrical systems. As usually understood with reference to alternating current, polarity is not ordinarily checked or a matter of concern in isolated systems. Although consistency in wiring orientation is advisable for explosion-proof outlets, that consistency is rarely carried to connected equipment, and it is not prescribed by code.