FIDOL represents frequency, intensity, duration, offensiveness and location. FIDOL is used as a means to characterize the effects of an odour annoyance.
Characterize an odour by its:
- Frequency – how often a person is exposed to an odour
- Intensity – strength of the odour
- Duration – the length of time of the detectable odour episode
- Offensiveness – hedonic tone of the odour;
- Location – relates an odour source with respect to land use. For example rural smells would be more accepted in rural areas versus urban areas.
From the five factors of FIDOL, offensiveness is difficult to quantify while the other four factors are quantifiable and may be subject to a regulatory guideline.