In efforts to reduce illness and injury within the plastics industry, safety measures must be followed meticulously. Through stable well-established safety procedures and consistent training, these injuries can be avoided and eliminated.

Molding Machinery—Features for Safety

A horizontal injection molding machine has 10 distinct features. It is important to know the functions of each feature in order to comply with O.S.H.A. safety measures and machine safety operation.

Distinct Horizontal Injection Molding Machine Features —10 Operator’s Safety Features

  1. Control Panel
  2. Electrical Cabinet Guards
  3. Hopper
  4. Hoses and Fittings
  5. Hydraulic Safety Interlock Valve
  6. Moveable and Fixed Front and Rear Guards
  7. Operator’s Gate
  8. Purge Guard
  9. Robot
  10. Under Guard

Control Panel

A red emergency button located on the front side control panel of the horizontal injection molding machine stops any movement of the machine when engaged.

Electrical Cabinet Guards

This guard covers electrical wires and components protecting from voltaic hazards. Electrical cabinet guards’ secondary objective is to guard against unauthorized use.


The Hopper guards the area where resin is fed through the horizontal injection molding machinery. It protects against accidental insertion of extremities into the machine while the machine is in motion.

Hoses and Fittings

Hoses and fittings can be hazardous if they wear out. Hot oil can spew causing burn injuries and can even cause fires. Hose and fittings inspections are necessary. Personal Protective Equipment (PPE) is always required. 

Hydraulic safety interlock valve

These valves keep the molding machinery’s clamp from engaging unless the operator’s gate is closed.

Fixed and Moveable Front and Rear Guards

Fixed guards on some models, moveable front and rear guards protect against contact with the operator and the molding machinery’s moving parts while the machine is running. The machine should not be engaged unless the movable front guard is in place. The moveable rear guard should only be accessed for maintenance.

Operator’s Gate

The operator has mold access through the operator’s gate. It is suggested that electrical and hydraulic interlocks be an integral part of the operator’s gate, machine’s operations, and set up in order to initiate operation. Only after this gate is latched should the machine resume movement. Reaching inside the gate while the machine is running is prohibited.

Purge Guard

Covering the machine’s nozzle, the purge guard prevents burn injuries and crushing injuries. It is suggested that electrical and hydraulic interlocks be an integral part of the purge guard molding machinery operations.


Robots prevent injury during tasks that may be hazardous, or repetitive tasks that may potentially endanger and operator. Robots are attached to the machine or adjoined to the horizontal injection molding machinery and is guarded to avoid hazards while the machine is in motion.

Under Guard

Protecting the area beyond the operator’s gate, the under guard keeps the area free from reach. Place a guard at the opening for parts discharge to prevent an employee from operator reach while the horizontal injection molding machinery is in motion.