Odor Sampling : Establishing appropriate protocols
Depending on the goals and the configuration of the source, odor sampling is typically carried out according to one of the following methods:
- Surface sampling through the use of a dynamic flux chamber. The approach allows for the determination of the surface odor flow rate from an unchanneled source such as a windrow, stockpile or lagoon.
- Point source sampling: Typically accompanied by a measurement of the flow rate. Used for sources with significant and confined flows and for efficiency assessments of abatment systems. In certain cases, ambiant sampling (inside a confined space or structure) can also performed.
A surface source is defined as a source of diffuse emissions over an area. Landfills, contaminated sites, compost and manure piles, waste water treatment lagoons, spreading fields are examples of such sources. Gas or odor sampling from surface sources is carried out using inert materials (sampling bags, piping, connections and all surfaces in contact with the gas).
The Odoflux™ flux chamber consists of a cylindrical enclosure with a spherical top. The flux chamber is supplied with a controlled flow of ultra pure air from a cylinder. The sample is taken from the chamber at a controlled flow rate to fill the inert sampling bag. The method allows for the calculation of a flux rate in g/m2-s or in o.u./m2-s.
Point source sampling
A stack, a conduit, a room or a static sample are all candidates for point source sampling. Depending on the characteristics of the source, a protocol may imply sampling and speed measurements according to established guidelines (at various points and at a specified distance of any disturbance).
Additionnally, specific issues such as high humidity, particulate levels, stack temperature or harsh climatic conditions (winter) may require specific protocols to be developped (heated sampling, dynamic dilutions, etc.) to avoid condensation in the sampling train and the samples themselves.
Of course, for both approaches, sampling conditions are to be thoroughly documented (ambient conditions, source conditions, processing data/rates, etc.) for later analysis.
Filled samplings bags are protected from sunlight and heat and are rapidly shipped to the lab where the qualified jury awaits to conduct the analyses in the shortest possible timeframe. In addition to odor concentration measurements, our laboratories can carry out odor intensity measurements, and investigations of odor synergies and hedonic tone.