One of the most common hazards from playing badminton outdoors, or playing outdoors in general is the sunlight and the heat from the sun.  In 2018, there was a massive heat wave that arrived at Quebec, and people who weren't able to avoid the heat wave suffered injuries. Around 54 people died in the heatwave!

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This is an important case to understand that you have to prepared wherever you go. I was playing badminton a lot outdoors during the summer, and the intense heat from the sun really made me lose energy fast. It was important to keep hydrated and have intermittent rest inside a shaded area to prevent health concerns. Once you sweat, you're also sweating out a lot of sodium from the body. When water and salt are lost from the body from sweat, you may have dehydration and muscle cramps. Drink some sports drinks to replenish electrolytes, and this can help with delaying or preventing muscle cramps.

Sunlight is also a big factor in danger in the environment. Ultra-Violet Rays (UV rays), although seemingly a great way to get tanned, is harmful for your skin and body. If you are out in the sun for too long, sunburns can form. I remember when I had my first sunburn, in where my skin was taut and red, and it would peel causing me tremendous pain. Sunburns are probably the most common injuries that occur from the sun. Always be aware of the time that you are spending in the sun, get plenty of shade, and don't forget to apply the sunscreen.