Paragraph 3 Apparatus

Test tubes shall conform to British Standard 3218:1982, nominal size 150/16, and shall be accurately marked at 10 ml. They shall be plugged with cotton wool or covered with closely fitting aluminium caps or stored in such a way as to prevent contamination.

Pipettes shall be 1.0 ml. straight-sided blow out delivery pipettes, and shall be plugged with cotton wool at the upper end.

Glassware and rubber stoppers shall be sterile immediately before use.

The water bath shall be fitted with a reliable automatic thermo-regulator capable of maintaining the water at a temperature of 37.5°C.±0.5°C.