Lux Hours

Lux Hours is an easy‑to‑use tool for monitoring the light exposure of items in display cases. You tap a slot on a drawn case and the app ranks each stored piece according to the measured light level, indicating whether it is allowed or too bright and how long it can remain there.

The app calculates a piece’s annual lux‑hours by multiplying the lux of each slot by the museum’s opening hours, summed over the past twelve months. It then compares the result with CIE 157:2004 limits for different material types, showing the values on a bar and a curve with the limit line drawn across.

When a piece reaches its limit, the slot shows the exact day and the remaining lux‑hours. After checking a lux meter, you can adjust the reading with a stepper and the app immediately tells you whether the current level is within the material’s limit.

Trustees can export a light record for every item, including its yearly lux‑hours and its share of the allowed limit, ready to be sent as plain text.

All content is included in the app and works completely offline. With Lux Hours, your favorites, notes, progress, and personal data are stored only on your device, with no registration, accounts, or cloud synchronization required.