(a) A permitted brand of sodium orthophenylphenate in a proportion of at least one pound to 12 gallons of water is permitted in tuberculosis eradication work for disinfecting infected premises following the removal of cattle that reacted to the tuberculin test.

(b) It is absolutely necessary that the solution be applied at a temperature of 60 °F. or over. Whenever the temperature of the building to be disinfected is below 60 °F., as indicated by a wall thermometer, the solution shall be heated to 120 °F. and higher in very cold weather, to insure effective disinfection.