PRESENCE-SENSING DEVICE INITIATORS IN PUNCH PRESS OPERATIONS Produced by the Industrial Health and Safety Program and Professional and Specialized Services, Ministry of Labour. Disponible en fran¨ais. HAZARD SUMMARY: Unintentional triggering of presence-sensing device initiators (PSDI) caused two recent accidents that were reported to the Ministry of Labour. The initiators were used as substitutes for conventional mechanical palm buttons in activating punch presses. In both cases, amputations resulted. PSDI are being marketed as replacements for palm buttons to activate punch presses. Claims that they have ergonomic advantages over the buttons are being made. Two PSDI are used together on one punch press. Typically, they are U- shaped: a transmitter on one arm of the U directs an optical ray, usually infrared, at a receiver on the other arm. The operator inserts both hands into the U-shaped "tunnels" of each of the PSDI, breaking the optical rays simultaneously and thus sending a signal to the press to perform one cycle. As shown by the two recent accidents, inadvertent activation of the press is possible with these devices. Some manufacturers state clearly in their marketing material that PSDI are initiation devices only, not safety devices. LOCATIONS AND SECTORS: Manufacturing, automotive sector, fabrication shops, etc. REQUIRED ACTION: Wherever PSDI are installed as initiation devices in a punch press operation, the employer shall ensure that adequate protection for the worker is provided. This would involve installations such as point-of- operation safeguards, measures to prevent accidental activation of the PSDI, etc. If the PSDI has been installed on a punch press without adequate safeguards, the employer should: - stop the press from being used, and - provide appropriate point-of-operation safeguarding or measures to prevent accidental activation before the press is used again. If these precautions have not been taken, orders shall be issued by the Ministry of Labour inspector. The Ministry is presently studying adequate safeguards for PSDI which are to be used as initiation devices. The results of this study will be communicated to clients when it is completed.