Minnesota Administrative Rules
Agency 144 - Health Department
Chapter 4720 - PUBLIC WATER SUPPLIES
Part 4720.0030 - FLUORIDATION

Subpart 1. Application.

This part shall be applicable to all municipal water supplies, as required by Minnesota Statutes, section 144.145.

Subp. 2. Fluoride content.

The fluoride content of the water shall be controlled to maintain an average concentration of 0.7 milligrams per liter; the concentration shall be neither less than 0.5 milligrams per liter nor more than 0.9 milligrams per liter.

Subp. 3. Chemical feeder.

The chemical feeder apparatus for introducing fluoride to the water supply shall conform to the standards of the commissioner of health.

Subp. 4. Testing.

Equipment for the adequate and reliable testing of the fluoride content shall be furnished for each installation. The method of testing the fluoride content of the water shall be approved by the commissioner of health. Approval shall require either a photometric colorimetric procedure, preceded when necessary by distillation or other treatment to remove interfering materials, or a fluoride-specific electrode and an associated potential measuring device. Continuous monitoring systems shall be approved when they can be installed to monitor a representative portion of the entire supply.

Subp. 5. Samples collected daily.

Samples shall be collected daily at a point(s) in the distribution system representative of the entire supply. Sampling point(s) shall be located downstream sufficiently distant from the point(s) at which fluoride is fed into the water supply to ensure that the distance traversed and the time elapsed since the introduction of the fluoride concentrate is adequate to allow its complete mixing with the water. At least once each three months, at a time designated by the commissioner of health, a duplicate of the usual daily sample(s) shall be collected in containers furnished by the commissioner of health and sent to the Department of Health for comparative analysis.

Subp. 6. Records of fluoridation.

Daily records of water fluoridation plant operations shall be maintained by the owners, officials, or their representatives. These records shall show the amount of water pumped, amount of fluoride chemical fed, fluoride test results, and any other pertinent information required by the commissioner of health. A report of the operation of each water fluoridation plant shall be submitted monthly to the commissioner of health on forms furnished by them.