One way to reduce distractions and reach flow state at work
One of our practices to protect private hours was that between 1 pm and 3 pm we do not talk or disturb each other. If someone really needed to get in touch with a colleague, they used Slack. This action was intended to eliminate interruption when being in flow. Our other rule about not disturbing wearing earphones is still in place.
Nowadays, our working hours are even more flexible and we often work remotely, but we still take effort to help each other reach flow state at work.