American Chemical Society (ACS) Laboratory Safety Test 2025 – 400 Free Practice Questions to Pass the Exam

Ultraviolet (UV) light is categorized into different regions based on its wavelength, which can have varying effects on biological tissues. The UV spectrum is generally divided into three main ranges: UVA (320-400 nm), UVB (280-320 nm), and UVC (100-280 nm).

Wavelengths shorter than 250 nm belong to the UVC range, which is particularly harmful due to its high energy. This energy is sufficient to cause direct damage to cellular DNA and contribute to the formation of harmful reactive oxygen species. Such damage can lead to cellular mutations, skin cancer, and other serious health risks. Additionally, UVC radiation is commonly produced by certain types of UV lamps used in laboratories and sanitation, making it important to consider this range as dangerous.

The other ranges of UV light have varying degrees of potential harm, but wavelengths in the UVC range are generally recognized as the most hazardous. Wavelengths longer than 400 nm are considered less dangerous as they fall into the UVA range, which, while still capable of causing skin damage with prolonged exposure, does not have the same level of immediate threat posed by UVC radiation. Thus, identifying wavelengths shorter than 250 nm as dangerous is accurate based on their known effects