I do need to explain the scientific method we apply. All odours are chemical. So to identify the so-called terror odour, we had to collect the various smells as a mixture of chemicals in the atmosphere when a particular victim was being delivered to a torture chamber for treatment.
Identifying and neutralising "normal" odours arising from this trauma, such as sweat and urine, is relatively simple, because we know their chemical composition. Over a period of time, we were able to isolate the chemicals making up the residual odour, which we believe is the terror smell.
We concentrated those chemicals and now use them in the experiments previously described, requiring subjects to sniff the concentrate.
I hope that clarifies things