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In this paper we analyze an experiment for the use of low-cost gas sensors intended to detect bacteria in wounds using a non-intrusive technique. Seven different genera/species of microbes tend to be present in most wound infections. Detection of these bacteria usually requires sample and laboratory testing which is costly, inconvenient and time-consuming. The validation processes for these sensors with nineteen types of microbes (1 <i>Candida</i>, 2 <i>Enterococcus</i>, 6 <i>Staphylococcus</i>, 1 <i>Aeromonas</i>, 1 <i>Micrococcus</i>, 2 <i>E. coli</i> and 6 <i>Pseudomonas</i>) are presented here, in which four sensors were evaluated: TGS-826 used for ammonia and amines, MQ-3 used for alcohol detection, MQ-135 for CO₂ and MQ-138 for acetone detection. Validation was undertaken by studying the behavior of the sensors at different distances and gas concentrations. Preliminary results with liquid cultures of 10⁸ CFU/mL and solid cultures of 10⁸ CFU/cm² of the 6 <i>Pseudomonas aeruginosa</i> strains revealed that the four gas sensors showed a response at a height of 5 mm. The ammonia detection response of the TGS-826 to <i>Pseudomonas</i> showed the highest responses for the experimental samples over the background signals, with a difference between the values of up to 60 units in the solid samples and the most consistent and constant values. This could suggest that this sensor is a good detector of <i>Pseudomonas aeruginosa</i>, and the recording made of its values could be indicative of the detection of this species. All the species revealed similar CO₂ emission and a high response rate with acetone for <i>Micrococcus</i>, <i>Aeromonas</i> and <i>Staphylococcus</i>.