IRSST - Institut de recherche Robert-Sauvé en santé et en sécurité du travail

Working Safely on Plastic Injection Moulding Machines

  •   May 25, 2017

Montréal, May 25, 2017 -  A study has just been published on the safety of workers operating or performing maintenance on plastic injection moulding machines that interact with peripherals such as robots, conveyors and granulators. By analysing accident reports, referring to the standards and carrying out a series of on-site observations, the researchers were able to determine the relevant risks and consider ways of reducing or eliminating them. Collecting this information helped the researchers arrive at a more concrete assessment of the reality faced by workers in the plastics processing industry who are exposed to hazardous situations that can sometimes be fatal.

The accident analysis highlighted a number of shortcomings to do with the strict enforcement of procedures, the bypassing of protective devices, familiarity with procedures and taking worker needs into account when designing and applying risk reduction measures. “For example, in many cases, there were no guards or else they were damaged, not functioning or incompatible with the work situation,” said engineer and lead researcher Yuvin Chinniah.

The researchers visited six mid-sized or large factories that all had safety officers or health and safety committees. They noted multiple technical and organizational risk factors, but were able to determine 43 means of risk reduction, only 5 of which were used in the six factories, i.e., requiring deliberate manual action to put a system or part of a system back into operation; antiskid surfaces; safety footwear; inspection of hoisting accessories; and the organization of heavy objects near the mould area. The researchers’ observations did, however, show that in most companies, “all the identified hazardous situations were addressed by at least one means of risk reduction.”

In defining best work practices to ensure worker safety in the mould area of an injection moulding machine, the researchers determined three characteristic risk reduction measures: (1) the use of a “partial lockout-tagout” procedure to prevent start-up by a third party; (2) the use of safety functions, such as interlocking movable guards with or without guard locking, pressure-sensitive mats for detecting whether someone is present, and emergency stop controls; and (3) inspection.

The findings of this study published by the Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST) are available for free download at


Jacques Millette
Public Affairs