In military and first responder training, malodor (i.e., unpleasant odor) exposure is common. First responders are required to perform life-saving interventions during highly stressful events.

The purpose of this longitudinal study was to research tourniquet application reaction times with malodor exposure.  Participants were randomly assigned to one of three groups, in two parts.  The two parts were separated by approximately forty days.  Part 1 had seventy-one participants, while Part 2 had fifty-eight participants.  Group 1 was exposed to malodor in both parts, Group 2 was not exposed in Part 1, but was exposed to malodor in Part 2, and Group 3 was not exposed in either part.  All participants received tourniquet training via videos, flash cards, and application to an arm. The culminating event was a timed tourniquet application to a leg.

The results revealed that malodors did not negatively impact performance.  Groups 1 and 2 (exposed to malodors during Part 2) reported a slight increase in perceived odor but did not suggest a negative impact.  These two groups also applied the tourniquet faster, maintaining the same accuracy with possible odor adaptation.  Group 1 (receiving odors during both parts) increased performance (faster tourniquet) over the other groups.  Group 2 (exposed to odors during Part 2) significantly outperformed their reaction time during Part 1 (no exposure). It is important to note Group 3 (not exposed to malodors in either part) did not perform as well as the groups that were exposed to malodors. The results from this study suggest that the addition of a malodor, in the proper context, may improve performance without having a negative impact on subjective measures.