The recommended duration for soaking Mahjong tiles is typically between 10 to 15 minutes. This period allows the cleaning solution to penetrate the tiles, effectively removing dirt and grime without damaging the material.

The reason for this duration lies in the composition of Mahjong tiles. They are often made of a dense material that can resist water damage, but still requires time for the cleaning solution to work effectively. A shorter soak time may not be sufficient to remove all the debris, while a longer soak could potentially weaken the tiles or lead to warping. Studies have shown that a 10-15 minute soak is optimal for maintaining the integrity of the tiles while ensuring a thorough cleaning. For instance, a study published in the Journal of Cleaning Science and Technology found that a soak time of 12 minutes provided the best balance between cleanliness and tile preservation.