1.  Dry heat at a temperature of 320 degrees Fahrenheit (160 degrees Centigrade) for at least 1 hour and preferably 2 hours;

2.  Steam pressure sterilization (autoclave), approved by the City Health Officer;

3.  Needles must be thoroughly cleaned with soap and water after each use.  To prepare for sterilization each needle shall be flushed with freshly distilled water and left distinctly moist, just before being placed in the sterilizer.  The tubes containing the needles shall rest on their sides in the sterilizer to facilitate air removal and steam intake to each tube and needle.  Under these conditions the exposure period is 30 minutes at 250 degrees Fahrenheit, followed by drying for not less than 15 minutes.