What ambient light level is sufficient for most tasks?

• A. 100 lux
• B. 300 lux
• C. 500 lux
• D. 50 lux

Answer: (B)

The main idea is that a moderate ambient level provides enough brightness for most common tasks without causing glare or eye strain. About 300 lux on the working plane is generally sufficient for typical desk tasks like reading, writing, and computer work, offering clear visibility with comfortable contrast. Levels around 100 lux or 50 lux are usually too dim for most activities, making it harder to see details and increasing eye strain. While higher levels like 500 lux can be beneficial for tasks requiring finer detail, they’re not necessary for the average task and can lead to glare or unnecessary energy use. Aim for a balanced ambient around 300 lux, and use task lighting to boost brightness where specific tasks demand it.