Code of Practice for Anti-termite Measures in Buildings, Part 3: Treatment for Existing Buildings
2001 Edition

The code recommends using Chlorpyrifos 20 EC (as per IS 8944) and Lindane 20 EC (as per IS 632), both at a concentration of 1% active ingredient, as primary chemicals for termite control in existing structures. These are applied as water emulsions for soil treatment to effectively manage subterranean termite infestations. Due to their high toxicity, strict adherence to safety precautions outlined in Annex C is essential to prevent health hazards and environmental contamination. Proper application and periodic re-treatment are vital to ensure long-term termite protection.

To create a protective chemical barrier in the soil, drill vertical holes approximately 12 mm in diameter at intervals of 300 mm along joints, cracks, and expansion areas within the plinth zone. Using a hand-operated pressure pump, inject the recommended chemical emulsion until resistance is felt or up to a maximum of 1 litre per hole. After injection, seal the holes to maintain barrier integrity. This method ensures uniform chemical distribution beneath the building, effectively preventing termite ingress through soil and structural openings.

Infested timber that is repairable should be treated by drilling 3 mm diameter holes at a downward angle into concealed surfaces of the wood, spaced about 150 mm apart, covering the entire affected framework such as door frames, shelves, and joints. These holes are then thoroughly infused with the specified chemicals. For unpainted or unvarnished wood, two coats of the chemical preservative should be applied on all surfaces, including crevices adjoining masonry. At wood-to-masonry junctions, drill 6 mm holes at a 45-degree angle and inject chemical emulsion until refusal or a maximum of 0.5 litre per hole, then seal the holes. This approach eradicates termites while preserving the existing wood.

Early detection involves a thorough inspection of areas in contact with or near soil such as basements, ground floors, steps, columns, and porches. High moisture zones like bathrooms and places with leaking pipes should be carefully checked. Key signs include the presence of winged termite swarms or discarded wings, earth-like mud tubes on walls or foundations, surface blisters on wood, and hollow sounds when tapping timber indicating internal damage. Regular periodic inspections help identify early infestations, allowing prompt removal of affected material and chemical treatment to prevent spread.

Due to the high toxicity of chemicals like Chlorpyrifos 20 EC and Lindane 20 EC, handlers must wear appropriate personal protective equipment including gloves, protective clothing, and masks to prevent skin contact and inhalation of vapors or sprays. Applications should be carried out in well-ventilated areas, with all containers clearly labeled, securely closed, and stored away from children and pets. Avoid applying chemicals near water sources to prevent contamination. Immediate washing after exposure and adherence to first aid protocols per IS 4015:1998 are critical. Only trained personnel should manage these substances, following detailed precautions in Annex C of the standard.