olfactometers

Olfactometers are instruments designed to present odor stimuli under controlled conditions. They are used in sensory science to study human olfaction and in environmental odor assessment to quantify odor strength. The key idea is to deliver precise concentrations of odorant vapors to a test subject or detector, typically by diluting an odorant carrier with clean, odorless air.

There are several configurations, with dynamic or air-dilution olfactometers being the most common for human testing. In dynamic olfactometry, odorized air streams are mixed with clean air in a computer-controlled manner to produce brief pulses or steady concentrations. This enables experiments such as detection thresholds, recognition tasks, and intensity judgments. In environmental monitoring, dynamic olfactometry is coupled with trained panels to determine odor concentration in odor units per cubic meter (OU/m3) following standards such as EN 13725.

Operation relies on stable flow, temperature, and humidity, as well as careful calibration to avoid contamination and odor carryover. Samples may be generated from liquid or solid odorants and presented through a nosepiece or sniff port.

Applications span product development, quality control, regulatory odor assessment, and research on olfactory perception. Strengths include reproducibility and the ability to quantify odor exposure; limitations include panelist variability, adaptation effects, and the need for maintenance and sanitization.