Sorry, but I strongly disagree. To each his own, but I think
caution and safety first is the number one priority.With mine, Momma chin and her kits are allowed to take their first dust bath when the kits are 10 days old and not before. Momma will teach her little ones how to do it properly.
If there is any irritation or raw areas on my momma or her little ones, they must all wait till the one is healed, if they are all going to be in the same cage together.
Chins will often urinate in the dustbath dust, this and any other moisture in the dust bath dust will support growth of germs that might get into the exposed raw skin can set up an infection ... a problem you really do not want to have with a mom and her new litter.
Please, check with your vet ... I have the feeling he/she will tell you not to allow the dust baths until day 10 if they are familiar with chinchillas and their care.
Jo Ann