When the 2011 Tohoku earthquake and tsunami struck, one of the biggest headaches for many areas became how to dispose of waste from toilets that were no longer in service due to power outages, disruptions of water supplies or broken mains.

The situation with toilets at the time of any natural disaster directly affects health and hygiene. Improving the situation, therefore, became an urgent task.

"You couldn't use the sewer and the stench was horrible," said Kazuma Morino, head of the ACT Institute of Disaster Medicine, whose nonprofit organization helped conduct a training course for medical professionals at Maebashi Red Cross Hospital in Gunma Prefecture last year.