Unlike lockout/tagout, which is intended to control hazardous energy during maintenance, repair, or inspection of a machine, “machine guarding” is the engineered control of hazardous energy during the normal operation of a machine. Machine guarding requirements can be found under OSHA 29 CFR 1910.212 General Requirements for All Machines, as well as in industry specific regulations like OSHA 29 CFR 1917 relating to marine terminal operations and equipment.
What constitutes hazardous energy? A machine, process, or device may contain a variety of forms of hazardous energy including:
- Electrical energy
- Pneumatic or hydraulic pressure, typically stored in pressure vessels
- Mechanical energy (i.e. springs, gravity)
- Thermal energy
- Chemical energy
Engineered elements of machine guarding may include some or all of the following:
- A fixed barrier between the operator and moving parts of the machine.
- An interlocked barrier that disables and stops the machine when the barrier is opened during normal operating processes.
- Emergency stops, operator machine control stops, and operation key stops.
- Lockout/tagout for processes that require regular processes for the operator in proximity to hazardous energy. Per 1910.147, the engineering and administrative methods for lockout/tagout of a machine may also become part of the normal production process for a machine in the event operators or indirectly exposed employees have to remove or bypass normal protective devices or policies as a regular part of the production process.
- Pressure-sensing pads that require the operator to be at a certain station before the machine will operate.
- Laser or light barrier curtains that disable a machine if an object crosses a certain plane or region.
- Adjustable and/or mobile guards that accommodate a variety of processes.
- Function-enabled switches that require operators to be at a certain station before the machine can be enabled and operated.
If you have a machine guarding or lockout/tagout case or claim, ARCCA’s engineers have the multi-discipline background to assist.