(a) Treatment with approved chemicals shall be in accordance with label directions as follows to foundation walls, piers, and chimneys:

1. (1) To all cracks in concrete;
2. (2) To mortar joints, cracks, and voids in the horizontal layer of masonry (stone, brick, concrete blocks, and tiles) which is adjacent to the treated ground at the bottom of the trench; and
3. (3) To voids between walls, as in brick veneer and stucco construction.

(b) Note 1.

1. (1) When the foundation wall is of hollow masonry blocks and the blocks are not capped with metal or solid concrete, each void should be drilled and injected with chemical unless specified otherwise by the label directions.
2. (2) This should be done even though there is no visible sign of infestation.

(d) Note 3.

1. (1)

   1. (A) Sections 54-415 – 54-417 of this part do not permit spot treatment of dwellings.
   2. (B) The license holder is held responsible for the entire structure on one-family dwelling units.

2. (2)

   1. (A) Commercial, industrial, and institutional buildings may, however, be spot treated at the license holder’s option.
   2. (B) The license holder’s responsibility in such cases shall be limited to retreatment and repair of the area spot treated, provided the area is shown on the graph, described in the contract, and understood by the property owner before the contract is signed.