Here's why:
* UV Exposure: Windows (especially older ones) often don't block all UV rays. Even a small amount of UV exposure can damage your hair, making it brittle and prone to breakage, especially when combined with the harsh chemicals in bleach. Some windows, especially tinted ones, offer greater UV protection but it is better to be safe than sorry.
* Bleach Fumes: Bleach emits fumes that can be harmful to your lungs and irritating to your eyes, nose, and throat. Being in an enclosed space, even near a window, can concentrate these fumes. Proper ventilation is crucial when bleaching hair.
* Uneven Processing: The natural sunlight filtering through a window can cause uneven lightening, as some areas of your hair will be exposed to more light/UV than others.
* Heat: The sunlight passing through the window can also heat the hair, which can speed up the bleaching process unevenly and damage the hair.
Instead, follow these safety measures when bleaching your hair:
* Proper Ventilation: Bleach your hair in a well-ventilated room. Open windows and use a fan to circulate the air.
* Protective Gear: Wear gloves to protect your skin from chemical burns. Consider using an apron or old clothes to avoid staining.
* Follow Instructions: Carefully read and follow the instructions on the bleach product. Do not leave the bleach on longer than recommended.
* Strand Test: Always do a strand test before applying bleach to your entire head. This helps you determine how your hair will react to the bleach and avoid unexpected results.
* Use a Timer: Set a timer to ensure you don't leave the bleach on for too long.
* Professional Help: If you're unsure about bleaching your hair yourself, consult a professional hairstylist. They have the expertise and experience to safely bleach your hair and achieve the desired results.
In conclusion, while being near a window might provide some ventilation, it doesn't offer sufficient protection from UV rays or bleach fumes. Prioritize your safety and hair health by following the recommended precautions and seeking professional help when needed.