Which category includes safety devices such as two-handed trip controls?

The correct answer encompasses the idea that the category of safety devices includes a range of mechanisms designed to enhance worker safety, such as two-handed trip controls. These devices are intended to prevent accidents by requiring the operator to use both hands to engage machinery, ensuring that the operator's hands are away from dangerous zones during operation.

Safety devices like these fall under the broad umbrella of safety measures that can also include other forms, such as physical barriers (guards that are actual obstructions preventing access to hazardous areas) and location-based guarding (placing machinery in such a manner that minimizes risk). Each of these categories serves a crucial role in workplace safety, collectively ensuring a safer working environment through various means of hazard prevention and control. Thus, recognizing that two-handed trip controls are a type of safety device that fits within a larger framework of safety mechanisms justifies why the all-encompassing choice is appropriate.