One lid was sterilized by one tincture of iodine and alcohol tampon. The lids were exposed 0. 5, 1, 2, 4 and 6 min to air after there were sterilized as above method. Bacterial culture was done.

• 另取同样液体150瓶；分为A、B、C、D、E5组；每组30瓶；1根碘酊、乙醇棉签消毒1个瓶盖；分别于消毒后放置0.；5、1、2、4、6min取样行细菌培养。