BS EN 47:2016 pdf download. Wood preservatives — Determination of the toxic values against larvae of Hylotrupes bajulus (Linnaeus) — (Laboratory method).
8 Procedure
8.1 Preparation of test specimens
8.1.1 Conditioning of test specimens before treatment
Allow the test specimens to condition in the conditioning chamber (5.3.2), for a minimum of two weeks.
8.1.2 Treatment of the test specimens
8.1.2.1 Preparation of the treatment solutions
8.1.2.1.1 Solid preservatives
Water-soluble preservatives:
— dissolve the preservative in the water (5.2.2) in a series of concentrations.
Non-water-soluble preservatives:
— dissolve the preservative in an appropriate solvent (5.2.3) in a series of concentrations.
8.1.2.1.2 Liquid preservatives
If appropriate, use the preservative without further preparation other than any necessary stirring If it is a concentrate, dilute the preservative with the diluent to the required working concentration, using the procedure specified by the manufacturer. All treatment solutions shall be freshly prepared. 8.1.2.1.3 Preparation Prepare a series of at least five concentrations by mass, distributed evenly about the expected toxic values. A solvent or diluent control, i.e. treatment at concentration = 0, shall also be used. If the approximate toxic values are unknown, the concentrations shall form a widely spaced geometric progression for a first test and a more closely spaced geometric or arithmetic progression for subsequent tests. All treatment solutions shall be freshly prepared. 8.1.2.2 Impregnation Carry out impregnation in ascending order of concentration, starting with the solvent control (concentration = 0). The following procedure ensures the required complete impregnation of test specimens by the test solutions. For each concentration weigh each test specimen, to the nearest 0,05 g, and then stack the test specimens in one of the treatment vessels (5.3.5) so that as much of their surface as possible is exposed (e.g. by piling them crosswise). Ballast the stack of test specimens with the weights (5.3.6) to prevent them from floating later when the liquid is admitted. Place each beaker in one of the vacuum vessels (5.3.8), attach the vacuum pump (5.3.9) and reduce the pressure to 700 Pa. Maintain it for 15 min. Observe the proper safety measures for vacuum vessels. After this period, close the stopcock to the vacuum pump (5.3.9) and open the other stopcock to allow the solution of the preservative to be drawn into the treatment vessel. Keep the test specimens covered completely by the solution throughout the remainder of the impregnation process.BS EN 47 pdf download.