A rapid method for the determination of boron in borosilicate glasses by neutron transmission has been developed and is described. The glass sample is dissolved in 48% HF, placed in a polyethylene cell, which is located near a Ra-Be neutron source. The neutron source and sample cell are embedded in a paraffin moderator. The attenuation of the neutron flux, which can be related to the boron concentration in the cell, is maintained with a BF3, enriched 10B proportional counter. Boron determinations can be made in approximately 40 min with an accuracy of 1%. Owing to the low sensitivity (approximately 1mg) the major disadvantage of the method is the large sample size necessary. The method is however well suited for use as a quality control procedure. Several experimental examples of its use are given. For glasses in which the boron content is less than 10% the accuracy decreases. It is possible to take larger samples, but for glasses containing small amounts of boron, the concentration of other constituents in the glass will also increase and cause attenuation of the neutron flux.
