MATERIALS HANDLING
Overhead belts and rollers should be guarded to prevent nip point injuries and falling components
circumstances that both regulators and insurers deem dangerous enough to require explicit rules to prevent. However, rules can vary drastically
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between countries (and even within countries) to such an extent that the definition of what is safe and unsafe can appear subjective, and in some cases, can present more design and safety issues than the regulation is attempting to remedy. An example is the concept of “guarding by location.” Guarding that is the result of the physical inaccessibility of a particular hazard under normal operating conditions is called ‘guarding by location.’ Machinery may be safeguarded by location if the
afety regulations are rarely arbitrary. Tey are generally based on a history of reported injuries and fatal accidents caused by a set of
distance to dangerous moving parts is greater than the prescribed safety distance, which varies by jurisdiction. Most people readily accept that
conveyors and other machinery require safety guards when positioned near workers or walkways. Guarding by location is the assumption that when hazards such as a moving conveyor belt are positioned beyond the normal reach of a worker, they don’t require a guard. Yet they can still present a serious hazard.
HAZARDS FROM ABOVE By not requiring a physical barrier, guarding by location creates what can be considered an exception to the general requirements for the guarding of hazards in the workplace. For example, Te American Society of Mechanical Engineers (ASME) B20.1-2015 Safety Standard for
Conveyors and Related Equipment notes in section 5.9.2(a): “Remoteness from frequent presence of public or employed personnel shall constitute guarding by location.” Tere are several hazardous locations
that are beyond the normal reach of a worker when working or walking under or around elevated conveyors. Tese hazards are considered to be guarded by location, often found in or around nip points between the belt and return rollers or drive components such as pulley shafts, couplings, drive belts, gears and chains. Additional hazards from falling components may be inadvertently ignored if considered guarded by location.
REGULATIONS AND STANDARDS Regulations usually stipulate the distance at which conventional barrier guards must
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