Work Break Timer uses slow, gentle pulse effects for alarms and visual nudges to both guide the user and cater for silent alarms. Components will alternate background colour every 2 seconds to indicate wanring and suggestions. Whilst not technically “flashing”, this behaviour may cause discomfort to some individuals.
These effects are designed to comply with internationally recognized safety standards for flashing content, including guidelines for photosensitive epilepsy. These visual effects can be disabled and the app has been designed to still provide visual cues, but without the benefits of having a ‘silent alarm’.
The application’s pulse rate of 0.25hz is well within various safety thresholds:
- British Epilepsy Society: States that it is uncommon to be sensitive at frequencies less than 3 Hz (common trigger rates are 3-30 Hz).
- Web Content Accessibility Guidelines (WCAG) – SC 2.3.2: Requires content to flash no more than 3 times per second (3.0 Hz) or meet thresholds for low contrast and size.
- Americans with Disabilities Act (ADA): Limits fire-alarm flash rates to a maximum of 2.0 Hz.
Flashing Components in Work Break Timer:
These components can be individually enabled.
- Main Timer Panel / Full Screen Mode:
- Flashes when a timer runs out to compliment or replace the audible alarm, where silence is required.
- Alternates between black and white every 2 seconds for a total duration of 50 seconds, followed by a 10-second pause without alternating.
- This creates a slow pulse rate of 0.25 Hz, and provides a 10 second rest period, remaining well within safety limits.
- Start/Next Interval & Finish Buttons, End Timer, and Current Time Labels:
- Pulses when a timer runs out, or a break is recommended.
- These small buttons & labels alternate every 2 seconds, at a flash rate of 0.25 Hz.
These rates are intentionally low to provide a gentle, non-intrusive visual experience while adhering to accessibility and safety guidelines.
As a side effect of ensuring the app is fully inclusive for all users, slowing down the pulse rate to cater for those with extreme photosensivity has made the application feel less ‘naggy’ so it’s a win for everyone 🙂