Which of the following is a signal that work conditions may not be safe?

High winds and ice accumulation are clear indicators that work conditions may not be safe, especially for those involved in tower work. Wind can create hazardous conditions that affect balance and control when working at height, while ice accumulation can make surfaces slippery, leading to increased risks of falls or equipment accidents. These environmental factors can compromise the structural integrity of a telecommunications tower and hinder the worker's ability to perform tasks safely.

In contrast, low visibility and cloudy skies may pose challenges, but they do not inherently indicate a significant risk factor like high winds or ice would. Additionally, moderate temperature changes typically do not create immediate safety concerns unless they are extreme. Regular inspections are a proactive safety measure and suggest that the equipment and worksite are being properly maintained, which is a good practice rather than a signal of danger.