It is very important to use only treated bamboo for construction. Such bamboos have a much longer lifespan and when used properly they can prolong the life of a structure to over 30 years. Bamboo treatment methods vary. These methods prevent the invasion of pests and the removal of the nourishment (starch content) in the bamboo that attracts the insects.
This activity involves the treatment, cleaning and preparation of bamboo culms. that have been harvested. The treatment method that we have been employing in Nongbah Myrdon is done in two stages for construction grade bamboo. This intensive treatment completely removes the starch from the bamboo, and also eliminates any existing borers/termites in the internodes.
Pressure Impregnation (or Boucherie method) – A solution (made with boric acid/borax, or with Cooper Chrome Boron, CCB) of 10% concentration (1 kg of chemical in 10 litres of water) is applied with pressure at one end of the basal end of a freshly cut bamboo. This drives out the starchy sap and replaces it with the preservative solution. This method uses a pressurized cylinder filled with the preservative solution, a compressor pump for pressure, pressure nozzles, valves to regulate the solution flow, a pressure indicator, a pressure release and outlet nozzles fitted to the bamboos. The process takes about 30 minutes and about 6 to 7 bamboos can be treated in one go.
Soaking or Immersion – Small holes are drilled in the bamboos in the internodes and they are soaked in a long and shallow tank in a solution of Boric Acid and Borax for a period of 3 days, and then stored in the shade to dry. The ratio of the Boric Acid to Borax is 1:1.5 and the concentration of chemical mix should be around 10% minimum, i.e., 100 kg of the chemical mix in 1000 litres of water.
Currently, we have two pressure tanks pressed into the treatment activity and a single soaking tank, where we are able to treat up to 50 to 80 bamboos per day. Around 10 youth have been trained specifically in this treatment and preparation activity and about 5 youth are regularly involved in regular operations. For the past two years we have utilised the structures built by the Umsning Block office for a Solid Liquid Resource Management (SLRM) unit. All acitivities right from storage of raw bamboo, treatment process, cleaning and storage of treated bamboo is done here. are currently on the drawing board for the setting up of a formal bamboo treatment facility which would also be integrated with a bamboo fabrication set up.