Which of the following are key safety practices when operating a trencher?

The correct choice emphasizes the importance of performing regular maintenance and checking fluids as a key safety practice when operating a trencher. This practice is vital because it ensures that the equipment is in good working order, reducing the risk of malfunctions during operation. Regular maintenance helps identify potential issues before they become serious problems, thus safeguarding the operator and others nearby from accidents or injuries. Additionally, checking fluids like oil, fuel, and coolant is crucial because low levels can lead to equipment failure or overheating, which can pose significant hazards.

Other choices do not contribute positively to safe operation. Ignoring the manual can lead to improper use of the trencher, potentially resulting in accidents or damage to the equipment. Using the trencher without securing it presents a risk of the machine moving unexpectedly or becoming unstable, which can lead to serious injuries. Operating only during daylight hours is a beneficial practice for visibility but does not encompass the broader scope of safety that regular maintenance and checks provide. Thus, understanding and implementing key safety practices, including regular maintenance, is essential for safe trenching operations.