Final answer:
Protective eyewear should be worn when applying pesticides whenever the label requires it, during the mixing and loading processes, or based on employer directives adhering to OSHA guidelines to ensure a safe working environment.
Step-by-step explanation:
Protective eyewear is required to be worn when applying a pesticide in the following circumstances: A. When the label requires it or for mixing and loading. This is because pesticides can be hazardous, and it is important to minimize exposure to them to protect one's health. Wearing protective eyewear, such as goggles, can prevent harm to the eyes from potential splashes or mists of pesticides, especially during the mixing, loading, or applying stages. These stages present a higher risk of exposure to harmful chemicals.
Moreover, protective eyewear is beneficial when working with substances that could cause irritations or more serious harm to the eyes. It's also essential for protecting against ultraviolet (UV) radiation. This is particularly relevant for outdoor applications where sunlight can compound the risks of eye exposure to pesticides. Ordinary glasses provide some protection, but full coverage or specialized safety goggles are recommended for their ability to block most UV rays, specifically if the lenses are made of materials like polycarbonate.
In all cases, following the safety instructions on pesticide labels and adhering to OSHA guidelines is critical for maintaining a safe working environment. Employers must provide their workers with proper safety information and equipment, and workers should use personal protective equipment (PPE) like gloves, goggles, and safety aprons as directed to prevent pesticide exposure and associated health risks.