The BLRA's Small Container Working Party, in association with British Glass, has developed this specification for the manufacture of carbonated beverage bottles up to 6gm CO2/litre carbonation. A cider maker has also been involved in its preparation. The specification should be regarded as a reference document which stipulates minimum standards. A section covering "glass thickness" is included on page 5-6. Companies with any further specific requirements should deal with manufacturers individually. Some aspects of the specification have required extensive debate with the bottle manufacturers and one of the issues concerned hot end coating/treatments. The industry had requested a minimum body coating of 30 CTUs but the glass manufacturers have advised that the equipment used to measure the hot end coating value sometimes gave "false" zero or low readings depending on unevenness in the glass surface. For this reason, the manufacturers can only provide a"minimum average" value rather than an absolute minimum. It should be noted that the expression "defect" is not considered to be an appropriate term and that any faults should now be referred to as "imperfections". There are three categories of imperfection but the list is not considered to be exhaustive. It is proposed that the document be subject to a review process around November 1997, with particular reference to BS 7367 - Strength and performance of carbonated beverage bottles.
