Iowa Code § 215.22

The speed of a monorail scale operation used by a packer shall not exceed the manufacturer’s recommendation or specifications for accurate weighing under normal, in-use operating conditions. The operational speed shall be permanently marked on the indicating element. Adequate measures shall be provided whereby testing and inspections can be conducted under normal in-use conditions. Tare weights for trolleys or gambrels shall be registered with the department. The registered tare adjustment on the indicating element shall be sealed or pinned.