Determination of odour intensity and hedonic quality of the gas sample
The gas samples for the determination of odour intensity and hedonic quality are taken correspondingly to the samples for the determination of odour concentration by dynamic olfactometry, except for their pre-dilution.
To determine odour intensity and hedonic quality, a sample of the gas is given to each evaluator. Each evaluator is tasked with smelling the gas in the sample. The presentation of the gas sample is done by opening the sample and gently releasing the present gas, sniffing the sample two to three times to allow evaluator determination of the intensity, hedonic quality and type of gas, and then plugging it. A sample is given separately to assess the odour intensity, the hedonic quality of the gas and the type of odour. This procedure is designed to reduce the sensory load on the evaluators (fewer responses to the number of gas sample presentations – one presentation -> one response).
The results of the odour intensity are presented for a single sample as the arithmetic mean of the answers given by all the evaluators (scale: from 0 – no odour perceptible to 6 – extremely intense). On the other hand, when several samples have been taken from a single source, the aggregate (final) result is presented as the arithmetic mean of all the samples evaluated for that source.
| SCALE OF ODOUR INTENSITY |
| 0 undetectable |
| 1 very weak |
| 2 weak |
| 3 clear |
| 4 strong |
| 5 very strong |
| 6 extremely strong |
The results of the hedonic quality of the gas sample are presented in the same way (scale from -4 to +4)
| SCALE OF HEDONIC QUALITY |
| +4 very pleasant |
| +3 |
| +2 pleasant |
| +1 |
| 0 neutral |
| -1 |
| -2 unpleasant |
| -3 |
| -4 very unpleasant |
Please send inquiries regarding cooperation to the following address: rzeszow@ottoindustries.com.pl or via the contact form available on the website in the Contact us tab.