That's an excellent and very practical question. The short answer is: it depends entirely on the bin's material and construction. Many heavy-duty commercial and municipal outdoor trash bins are specifically designed to withstand high-pressure power washing, which is a common and efficient cleaning method in public spaces.
For instance, stainless steel and high-density polyethylene (HDPE) bins are champions here. Stainless steel is naturally corrosion-resistant and handles power washing beautifully. High-quality HDPE is tough, won't rust, and its smooth surface makes it ideal for blasting away grime. Many manufacturers explicitly state their products are "power wash safe."
However, the key is using the correct technique. You should use a wide-angle nozzle (40-degree is good) and keep the pressure washer at a moderate setting (around 1200-2000 PSI) from a safe distance of about 12-18 inches. Avoid concentrating a pinpoint jet stream on seams, decals, or locks, as this can cause damage over time. For bins made of thinner galvanized steel or with internal liners, check the manufacturer's guidelines first, as intense pressure can compromise coatings or cause water intrusion.
So, for most robust outdoor bins in parks, city streets, or commercial properties, power washing is not only acceptable but recommended for deep sanitation. Just match the cleaning power to the bin's build quality for the best, longest-lasting results.