Safety should always be the top priority in any industry. The right for all workers to be safe from hazards is the law as stated by the OSHA act of 1970. Modern machining processes are designed to eliminate or make manageable all hazards that might be faced by the operator. There are many ways to address hazard exposure in any process from administrative controls (rules, procedures, etc.) to more physical methods known as engineering controls.
One of the most effective engineering controls that can be applied is the design and installation of machine guarding at critical hazard locations. These include rotating equipment, reciprocating tooling, cutting or high temperature surfaces, and generally any moving machinery that may pose the risk of entrapment.
To be effective a machine guard needs to meet several criteria.
First and foremost, the machine guard must prevent operator and others in the vicinity contact with the hazard. Although this seems to be self-explanatory, a guard may cover the hazard but leave access during non-standard operations such as cleaning or clearing or to passers-by.
Second, the new machine guard must not create any new hazards. This means no sharp edges or locations where a body part might be trapped and injured between two or more surfaces (pinch points).
Third, the guard must not interfere with the typical operation of the machine. If this is the case, it is highly likely that the operator will bypass or remove the machine guard, thereby rendering it useless. The guard should also be secure, making removal or alteration difficult or impossible.
Finally, the guard is required to protect the machine from falling objects. An object such as a tool that falls into rotating equipment quickly becomes a missile, capable of injuring anyone in the area.
Physical barriers such as guards offer substantial protection from hazards when designed and implemented correctly. Other non-physical barriers such as light curtains and sensors are also good choices, although careful consideration must be given to these devices to ensure that all of the criteria are met. A light curtain might protect the employee by shutting down the machine, but it may not protect from objects falling in to the equipment. In comparison, a physical machine guard may cover the hazard, while causing the operator to perform other unsafe acts due to lack of access.
With good hazard observation, every machine can and must be properly guarded to operate safely.
With thanks to our guest blogger Rachel Daughtery of Accurate Forming