Most people have their own way of loading a dishwasher. And, of course, their way is “the right way.” Thankfully, a study has been conducted to put arguments to rest.

The study was conducted by engineers at the University of Birmingham. They analysed how water circulates inside empty and fully loaded household dishwasher. They used radioactive isotopes to monitor the speed and direction the jets of water travelled when the dishwasher was in use.

In the end, they found that not all places in the dishwasher are created equal. Dr Raul Pérez-Mohedano, who led the work at the department of chemical engineering at the University of Birmingham said that the team concluded that the most efficient way to pack your dishwasher is in a circle around the cutlery basket. He added that dishes should be packed according to the type of stain they contain.

Plates that need the full force of water, such as those caked in mashed potato, should be positioned immediately above the rotating arms of the dishwasher and in the centre of the top shelf. Meanwhile, dishes that require the detergent to have more time to work on them should be closer to the walls of the dishwasher at a height between 5cm (2 inches) and 20cm (8 inches) where velocities of the water are at their lowest.

According to the study, most commercial dishwashers are designed incorrectly. The ejection of water is produced in a circular movement, while the distribution of the crockery follows a rectangular pattern. This, according to Dr Pérez-Mohedano, means that there are areas where the impact of water is going to occur for longer. Naturally, the team also cautioned against overloading the dishwasher.

Dr Pérez-Mohedano hopes that the findings can be used to design more efficient and effective automatic dishwashers. He said that he thinks a redesign of the way of distribution of water is necessary. But, he is positive that dishwasher manufacturers are working on these inefficiencies. Dr Pérez-Mohedano noted that there are some ideas “that have been or are ready to be commercialised.”