Definition: “Guarded” means shielded, fenced, or enclosed by covers, casings, shields, troughs, spillways or railings, or guarded by position or location. Examples of guarding methods are guarding by location (positioning hazards so they are inaccessible to employees) and point of operation guarding (using barrier guards, two-hand tripping devices, electronic safety devices, or other such devices).
While OSHA’s penalties for machine guarding violations do not tell the whole story, they illustrate how much work remains in dealing with this “simple” problem with a scope that remains difficult to define. There is no doubt about it, machine and equipment guarding continues to challenge industry.
Unfortunately, the most common way to learn of a machine or equipment guarding shortcoming is when an injury occurs. Furthermore, accidents associated with improperly or inadequately guarded machines or equipment often produce more severe injuries.
The United States Bureau of Labour Statistics presents more disappointing data. Despite improvements during recent years, nearly 6,000 occupational amputations were recorded in the United States during 2009. Many of these amputations are products of improperly guarded machines or equipment or lockout violations.
Ignorance is no defence
While it is unknown how many of the referenced machine guarding injuries or violations were detected after the employer had taken action to adequately guard the equipment in question, the existence of such cases is well documented. For example:
Impact of improperly guarded equipment
While injured workers are the ultimate victims of accidents, their employers don’t escape unscathed, either. The business impacts of accidents and injury are both tangible and intangible. Cost leads the way in terms of tangible impacts, including increased workers’ compensation costs, OSHA penalties and legal fees.
Less tangible impacts can have even greater effect, however. When a worker suffers a serious injury, plants can expect:
Obviously, businesses do not want their workers to be hurt, endure enforcement actions or bear additional cost. So why do machine guarding problems persist? Perhaps the topic is not as easy to understand as it may seem. Consider the following:
One has to consider a myriad of variables in defining the proper machine guarding solutions. First, the equipment not only has to be properly guarded, but it also must continue to serve its production demands. Proper guarding strategies must consider all variables – production, set-up, tool changes, inspection, maintenance and abnormal or upset conditions.
Over the last 4 decades, machine guarding has progressed from largely a mechanical undertaking to one that is more electronically focused. Much of the manual machinery that was being used 40 years ago has been replaced by highly automated, computer-controlled equipment. The number of interlocks and interfaces associated with properly guarding automated equipment is not easy to understand.
Newer equipment is sophisticated and is produced by a growing number of global companies. Too many purchasers of newer equipment incorrectly believe that the equipment manufacturer is responsible for proper machine guarding. Purchasers also can gain a false sense of confidence through requirements that equipment “must be guarded in accordance with OSHA standards.” The fact that an equipment manufacturer accepts this requirement does not mean that they understand how to properly guard the equipment.
Machine guarding is like other technical functions – new products, approaches and requirements are continuously introduced. Few people have the time – or the ability – to keep pace. While OSHA does not approve equipment, approval by third parties (e.g., UL, ANSI and NFPA) is required or recommended for many machine guarding components.
When manufacturing operations struggle with limited resources, they may assign machine guarding functions to whoever is available whenever they can fit it into their schedules. In some cases, this means that the workers assigned responsibility do not have the technical background needed to understand and apply the proper technology. It also can mean significant delays in completing the guarding task while waiting for an opening in the schedule, researching options and the trials and errors of installation. Unfortunately, even after going through this process, there is no guarantee that the work will be properly completed.
Even manufacturing companies with broad and deep engineering resources may find it difficult to divert their technical resources away from core functions.
Machine guarding is a niche specialty. Even the most competent of internal engineers faces a learning curve to understand the complexity of the OSHA standards and application of the many consensus standards that are involved.
Many companies take a hybrid approach to machine guarding. It is not uncommon for an internal employee to identify the guarding need through an informal review. That person then may work with a local industrial equipment firm to specify guarding hardware and software. Design may be contracted or handled by other internal or external resources, while yet another contractor or internal maintenance team may complete the installation.
In this case, it can be difficult to identify the accountable party in the event of a question or problem. If no member of the ad hoc team has in depth knowledge of machine guarding technologies and requirements, it’s also possible the original project objectives of properly guarding the equipment while maintaining optimum productivity will be lost.
The Holistic Solution
Holistic machine guarding approaches include:
The comprehensive approach to machine guarding is useful when converting “zero injury” philosophies into reality.
The documented, machine-by-machine guarding risk assessments and the employee involvement fostered by the assessments directly support OSHA VPP recognition and OHSAS 18001 (Occupational Health and Safety Management System) registration efforts.
Holistic firms can work with equipment manufacturers to review and sanction guarding approaches for new equipment before it is shipped to the holistic firm’s customer.
Guarding designs and approaches can be used for identical pieces of equipment that may reside in multiple locations.
Machine guarding risk assessments can be used to qualify equipment for transfer from one country to another where different standards may be observed. Many emerging countries require such documentation before imported equipment can be sanctioned for use.
Consistent approaches to machine guarding results in better operation/maintenance and requires fewer spare parts in inventory. This is similar to the Southwest Airlines model of flying only Boeing 737s.