10 Common Machine Guarding Mistakes by Manufacturers

December 5, 2013

Why is machine guarding so important for manufacturers?

machine guarding plant safety mistakesAccidents in the manufacturing environment can be devastating. Not only can they lead to tragic loss of life or irreversible injury, they can bring an entire manufacturing operation to a screeching halt, costing millions of dollars. For moral, ethical, and financial reasons, avoiding manufacturing accidents should be the number one priority. At the end of the day, everyone wants to see their employees go home unharmed.

Our plant safety specialists have developed this list of the 10 most common machine guarding mistakes we have seen implemented by manufacturers. Are any of these mistakes happening in your manufacturing operation?

10 Common Machine Guarding Mistakes Implemented by Manufacturers

  1. Plant risk assessments and risk reduction plans do not dive deep enough; they do not take into account all interaction types with the use of machinery. Therefore, machine safeguards are typically defeated to meet needs of plant production.
  2. There are no specific safety standard requirements given to machine builders, systems integrators, or contractors. Typically, only the specification of a type of device or brand of device is given. This allows for some of the following situations to occur:
    a) There is no consistency in how “safe” each machine or process is designed and implemented
    b) Each design may not be as safe as it should be
    c) Safety devices are not mounted in accordance to the safe mounting distance formula (e.g. a light curtain mounted to a machine frame for convenience as opposed to complying with the safe mounting distance formula) creating “the illusion of a safety”.
  3. Safety devices are mounted and installed correctly, but not programmed or configured correctly – leading to the “illusion of safety” (e.g. laser scanner is mounted and
    wired correctly, but the programmed “safe zone” is too small or the wrong shape).
  4. Manufacturers believe that meeting Category 3 or Performance Level D circuit performance per ISO 13849-1 means your machine is “safe”.
  5. Maintenance staff is permitted to defeat machine safeguards to clear jams and clean equipment.
  6. The use of standard PLCs to “mute” safety functions during non-hazardous portions of a machine cycle/process (e.g. mute a light curtain when the machine is stopped).
  7. Misapplying and misusing protective stops, cycle stops, and emergency stops.
  8. Not including the pneumatic and hydraulic functions of a machine in the safety circuit.
  9. No secondary safeguards (either presence sensing devices or administrative procedures backed by a safety-rated control scheme) are in place where full body access is possible within a work cell.
  10. Rope-pull emergency stop devices not designed to detect “slack” in the line. This could lead to the rope-pull only working under “some” conditions.

Put an end to machine guarding mistakes by leveraging plant safety expertise

There are many things to consider when trying to combat current machine guarding mistakes and taking steps to tackle a plant-wide machine guarding project. It can be extremely advantageous to leverage the expertise and experience of companies who specialize in plant safety. When searching for a service provider capable of performing complete machine guarding projects, you must ensure the provider is able to demonstrate the appropriate expertise in entire safeguarding process. This includes:

  • Staying current on all national and international regulations
    and standards,
  • Conducting machine guarding assessments,
  • Developing risk reduction strategies at both a machine and company level,
  • Designing, installing and validating safety systems, and
  • Delivering machine safety training.

In addition to a third-party resource providing expertise where needed, they can also provide peace of mind. It is invaluable to know a job was done correctly, ultimately providing a work
environment for all employees.

machine safety guide buttonDownload our complete 26-page Machine Safety Guide for Manufacturers now as a first step to assessing your current machine guarding strategy to reduce machine down time, increase plant safety, and achieve continuous improvement in manufacturing.

Grantek’s safety team possesses the complete set of skills required for a truly complete safeguarding project. Grantek takes a comprehensive approach to machine guarding combined with a strong competency in automation leading to a fully integrated safeguarding solution, not just “adding guards” around your existing system.