Acoustic measurements of outdoor sites require researchers to carefully consider the appropriate method to ensure reliable results. This entails the consideration of the signal-to-noise ratio (SNR), the presence of visitors as well as restrictions that are specific to the site. The present paper presents the results of an experiment conducted in a controlled environment with the aim of comparing the reliability in the presence of different types of noise of three measurement techniques: the Exponential Sine Sweep (ESS) method using a 90-second sine sweep, this same method but with the application of time averaging of multiple measurements and the Inverse Repeated Sequence (IRS). The results are presented in relation to reverberation time and clarity parameters and demonstrate that under the test conditions the ESS method when used with a long sine sweep is the most dependable in the presence of the noise disturbances studied. These findings are of relevance for the application of convolution reverb in audio postproduction.