Table 2.

Results from validation of microbiological assessment

Micro-organism	Agar type	Test solution cfu	Positive control cfu (c)	Lower limit (c÷2)	Higher limit (c×2)	Pass/Fail*
Aspergillus brasiliensis	TSA	37	23	12	46	Pass
A. brasiliensis	SDX	50	47	24	94	Pass
Escherichia coli	TSA	34	24	12	48	Pass
Bacillus subtilis	TSA	50	37	19	74	Pass
Candida albicans	TSA	38	32	16	64	Pass
C. albicans	SDX	42	39	20	78	Pass
Staphylococcus aureus	TSA	38	53	27	106	Pass
Pseudomonas aeruginosa	TSA	41	36	18	72	Pass

*Validation passes if the number of colonies from the test solution does not differ by a factor greater than 2 from the number of colonies from the positive control solution.

Notes: Negative controls and environmental monitoring comply.

The system has been shown to be suitable when (1) between 10 and 100 cfu of each type of micro-organism are present in the positive controls; (2) there is no interfering growth in the sample; (3) there is no growth on the negative control; and (4) there is no growth on the settle plate.

cfu, colony-forming units; TSA, tryptone soya agar; SDX, sabouraud dextrose agar.