OSHA Directive: Slide-Locks Now OK for More Machines
On Dec. 21, 1998, OSHA issued an interpretation letter to General Motors prohibiting the use of slide-locks to replace safety blocks on mechanical power-presses. A slide-lock device is a positive mechanical engaging device capable of preventing a slide from closing of its own deadweight, and the letter said such devices would not meet the safety requirements contained in Section 1910.217(d)(9)(iv), which covers mechanical power presses. Now, however, because of improved technology and requests for further guidance on the subject, OSHA has issued directive CPL 02-01-043, effectively canceling that letter and establishing enforcement policy, inspection procedures, and performance guideline criteria regarding slide-locks when they are used for hazardous energy control purposes. The directive became effective Sept. 14 and applies OSHA-wide.
According to the directive, OSHA has reevaluated the use of slide-locks as energy isolating devices when used on mechanical power-presses (in place of safety blocks) and when used on other general machinery. The directive's appendix contains the Performance Guideline Criteria for Slide-locks, which includes design criteria addressing safety factor design. Compliance officers must use the guidance material contained in this directive when evaluating the adequacy of slide-lock use as energy isolating devices.
To view the directive, visit www.osha.gov/OshDoc/Directive_pdf/CPL_02-01-043.pdf.