Document ID: chunk:federal_register_of_legislation:F2007L04903:body:0:p3
Version: federal_register_of_legislation:F2007L04903
Segment Type: other
Provision Reference: 
Character Range: 5734–7880

reveal the grain direction and a drop of ink placed on a face of the piece of wood will spread most readily in the direction of the grain. A swivel handled scribe may also be used to determine the slope of grain in wood.

B — Alternative method for the determination of moisture content

      Take a small sample of the timber from the appropriate position, weigh it (W1) to an accuracy of 1% of its weight and then desiccate it in an oven at a temperature of 100C-105C until the weight is constant (WO), taking great care to prevent any change in moisture content between the cutting of the sample and the first weighing and also between removal from the oven and the subsequent weighing.

      Calculate the moisture content as follows:

      Moisture content, per cent =

C — Method for the determination of density

      Cleanly cut a sample, approximately 2.5 cm long and of the full cross-section of the board or plank, from each end of the piece at a position clear of weathering, where the moisture content is known or is about to be determined.

      Make a series of measurements of the length, width and thickness of each sample, obtain the arithmetic mean of each dimension and calculate the volume (V) of the samples in cubic centimetres. From each sample take the weight (W) in grams to an accuracy of ± 1% of its weight.

      Calculate the density as follows:

      Density =  kilograms per cubic metre

      where: — W is in grams
       V is in cubic centimetres.

D — Brittleness (Izod) test

       Test specimens

      Two samples must be cut from diagonally opposite edges from 1 end of the plank.

      A notched specimen, the sides of which are cut radially and tangentially, of the form and dimensions shown in Figure 1 must be prepared from each of the samples.

       Procedure

      The test specimens must be broken in an Izod impact testing machine, the blow being applied in the direction tangential to the growth rings. The testing machine must be of a type which will permit the test results being determined to within 0.3 joule.

      Figure 1 — Impact test specimen