225 ILCS 470/5

Weights and measures supplied to the State of Illinois by the federal government or otherwise obtained by the State for use as State standards shall, when certified to be satisfactory for use as such by the National Institute of Standards and Technology, be the standards of weight and measure of this State. The State standards shall be retained in a safe and suitable place in the office or laboratory of the Department and shall not be removed from the office or laboratory except for repairs or certification.