Safety first in conveying is a well talked about topic. Safety regulations are rarely arbitrary. Rather, they are generally based on a history of reported injuries and accidents caused by a set of circumstances that both regulators and insurers deem dangerous enough to require rules and regulations in place to prevent such circumstances.
What are safety guards?
Machine safety guards serve as physical barriers to various types of equipment. Once installed, they keep workers at a safe distance from moving parts, pinch-points, and other danger zones. This limited access equates to fewer accidents and injuries.
Guarding by location
However, these rules and regulations can vary quite significantly depending upon industry to such an extent that the definition of what is safe and unsafe can appear sometimes subjective. It is readily accepted that conveyors and other machinery require safety guards when positioned near workers or walkways, however this is not always the case. Guarding by location is the assumption that when the hazards such as a moving conveyor belt are positioned beyond the reach of a worker that a guard is not required. Yet they can still present a hazard.
Safety Hazards in conveying
There are several hazardous locations that are beyond the normal reach of a worker when working or walking under or around elevated conveyors. These hazards are considered to be guarded by location, often found in or around nip points between belt and return rollers or drive components such as pulley shafts, couplings, drive belts, chains, and gears.
A guard is a machine element that makes the danger zone inaccessible, by isolating it (section 172 of the Regulation Respecting Occupational Health and Safety). Guards on conveyor belts must be designed with operating conditions in mind.
They must be capable of resisting the loads to which they will be subjected. These devices must not create additional hazards or tempt workers to bypass their use.
The dimensions and weight of movable guard components must be designed to allow for easy handling. To this end, it is preferable to have articulated or hinged guards. Guard removal and reinstallation must be quick and easy. Ideally, guards should be self-locking when closed.
There are three types of guards:
- Fixed guards – Surrounding fixed guards, Barrier guards (fixed distance), Fixed in-running nip guards
- Interlocking guards
- Interlocked guards with guard lock.
Regulations are in place and usually stipulate the distance at which conventional barrier guards must be located, generally between 2.1m and 3.5m from the work surface, some regulations require greater distances.
Most regulations do not account for the potential build-up of spillage underneath conveyors or in walkways, which can easily change the distance between working surface and hazard.
Exemptions such as guarding by location do not fully address the dangers to the workers. As a result, rules defining the practice become ineffective as a safety measure, especially where belt conveyors are concerned. Despite its acceptance in various regulations, the practice of calling moving components on conveyors ‘guarded’ solely because the installation is at least a specific distance from the worker is outdated as a concept and ineffective in application.
Asmech Systems Ltd. recommend the full installation of guards to safeguard workers. For maximum risk reduction, all nip points, shear points and moving or rotating components should be guarded, regardless of location. We can help with your specific requirements.
Speak to a member of our safety team on 01623 424442.