Fig. 2

Retrieved colony forming units from alternative assays (oligotrophs, alkaliphiles, vegetatives, fungi and anaerobes) and bioburden measurements, grouped by sample origin. Horizontal lines and given numbers reflect the median of all samples taken at this certain timepoint in the respective cleanroom (source: Additional file 2: Table S2 and Additional file 4: Table S4). Boxes represent the first and third quartile. Red triangles refer to a median of 0. Colony forming units (CFUs) are given in a logarithmic scale (Y-axis). Colours indicate the different sampling campaigns, sampling locations are indicated (X-axis)