How can we justify using of precision balances, which are having only 4 decimals capacity? By using this balances we can do calibration daily with 10 mg? If we do, what will be the tolerance limit for this as per USP?

How can we justify using of precision balances, which are having only 4 decimals capacity? By using this balances we can do calibration daily with 10 mg? If we do, what will be the tolerance limit for this as per USP?