Safety of machinery: Hazardous energy control and LOTO management

Hazardous energy control and LOTO (Lockout /tagout) management in machine safety. 1. Why should we pay attention to LOTO? ● There are more than 5,000 deaths worldwide due to accidental release of mechanical energy each year, of which more than 90% can be avoided with proper LOTO management! ● China’s “Production Safety Law” clearly stipulates: “dangerous operations must take energy isolation measures, failure to implement the maximum fine of 2 million yuan!” Common risks on site: ● Misoperation Restart equipment: touch the button incorrectly during maintenance, resulting in sudden mechanical operation. ● Residual energy hurts: the hydraulic system is not emptied, and it is suddenly released during maintenance. ● Multi-person coordination chaos: multiple employees work at the same time, unlocking the wrong sequence caused an accident. Second, LOTO’s core principles: energy isolation “four-step method” step 1: Stop and notification ● Clear stop signal: press the emergency stop button, turn off the main power supply, and notify all affected personnel “equipment is about to be repaired, no operation”. ● Case warning: a factory did not notify the operator, resulting in the equipment was mistakenly started during maintenance, and the worker’s arm was involved in the machinery. The second step: isolation and locking ● “three locks and one card” principle: ○ The main power supply is locked with a personal lock, and the key is kept by maintenance personnel; ○ Collective work using collective lock box, one lock per person; ○ Hang a red warning sign: “Do not start, maintenance”. ● Key points: Isolation devices must be “visible to the naked eye and cannot be bypassed”, such as valve locks and electrical switch locks. The third step: verification failure ● three-step verification method: 1. Press the start button to confirm that the device does not respond; 2. Test residual energy (such as zero hydraulic pressure gauge); 3. Take photos to record the isolation status and retain evidence. Step 4: Unlock and restore ● Unlock order: the first person to unlock, the last person to confirm the safety of the collective lock box removed; ● Do not skip: unlocking directly without verification may cause the device to start suddenly!