Re-identifying smaller than #6 AWG conductors is not allowed because

Conductor Ampacity:
#6 AWG and larger conductors have a higher ampacity than smaller conductors. Re-identifying a smaller conductor (e.g., #10 AWG) as #6 AWG could lead to overloading and potential fire hazards.

Voltage Drop

Smaller conductors have a higher resistance than larger conductors. Re-identifying a smaller conductor as a larger conductor could result in excessive voltage drop, affecting the performance of electrical equipment.

Code Compliance

The National Electrical Code (NEC) and local electrical codes prohibit the re-identification of conductors smaller than #6 AWG. Changing the color code of a conductor violates electrical safety standards and could lead to confusion and potential hazards.

Safety Concerns

Incorrectly re-identified conductors can pose serious safety risks. If a smaller conductor is accidentally overloaded or subjected to a fault current, it could overheat, melt, or start a fire.

In your case:

The fact that #10 AWG conductors have been taped white in your installation raises concerns about potential safety hazards. It's strongly recommended that you consult with a qualified electrician to have the installation inspected and the conductors properly identified and labeled. Flag for review