IMO you need more data. Difficult to give an opinion based on 1 datum /area.
Do you clean, check ATP, sanitize, check micro. or ??
Were all the cleaned surfaces visually satisfactory ?
Are areas 1,2,3 likely to be similarly "contaminated" ?
ATP and micro.data are 2 ways of evaluating the "cleanliness" of a surface.
As noted in previous post microbiological testing may or may not correlate with ATP readings, since the two techniques measure different parameters. Microbiological methods detect residual micro-organisms (usually bacteria), which should decrease as a result of cleaning/sanitization (C/S). The magnitude of any decrease will depend on the method, materials and chemicals used. ATP bioluminescence is a measure of cleanliness that detects organic soiling (OS) (microbial and non-microbial ATP). (The non-microbial contribution to total ATP is frequently much greater than microbial.)
Despite the above comments, there are some published correlations also.
Verification cleaning efficiency, ATP vs micro..pdf 465.97KB
Ideally one would obviously like to achieve satisfactory results for both.
If all the data is representative of the routine C/S procedure and quantitatively reliable, suggests that -
Area 1 is OS unsatisfactory but micro.satisfactory (with respect to TPC/coliform)
Areas 2,3 are OS satisfactory but micro. unsatisfactory (with respect to TPC/coliform) (how much unsatisfactory depends on the quant. meaning of TNTC)
(I daresay you knew that already).
i suggest you should establish a baseline for both test procedures/sampling points/routine cleaning-sanitizing process. I think this is recommended by ATP unit suppliers.
Edited by Charles.C, 26 September 2015 - 12:39 AM.