That's an excellent and very practical question. The short answer is yes, metal urban trash bins can absolutely get hot enough to be uncomfortable or even painful to the touch when placed in direct sunlight, especially during peak summer hours.
Here’s a more detailed, natural explanation from my own experience and understanding:
Metal is an excellent conductor of heat. When the sun beats down on a dark-colored or even standard silver metal bin, the surface absorbs a significant amount of solar radiation instead of reflecting it. This is why you'll often find that bins with darker paint jobs get much hotter than lighter-colored ones. On a clear, hot day with temperatures around 90°F (32°C), the surface temperature of a metal bin can easily soar to 130-150°F (54-65°C) or higher. That's hotter than a typical hot tub and certainly enough to cause a quick, unpleasant burn or surprise, especially for a child, pet, or someone not expecting it.
You might have noticed this yourself when touching a car door handle or a metal playground slide in the summer. The same principle applies. The heat buildup is most intense on the sides facing the sun, and the lid can become particularly hot.
Is it a major daily hazard? For most aware adults, it's more of a momentary discomfort. However, it's a genuine safety consideration for public spaces. Responsible city planners and park managers are aware of this. You might see some mitigation efforts, like placing bins in partially shaded areas whenever possible, using lighter-colored, reflective paints, or even opting for modern plastic/composite bins in high-traffic family areas, which generally don't conduct heat as efficiently.
So, to answer your question naturally: Yes, they can get surprisingly hot. It's a good idea to be a little cautious when using public metal bins on a scorching day—maybe use the back of your hand or your elbow to open the lid if it's been sitting directly in the sun all afternoon. It's just one of those small, real-world physics lessons we encounter in urban life!