Tom Card and CE Schmidt have been conducting odor source assessment project for over 20 years.  The odor emission assessment protocol treats odor similarly to any other study compound where sample collection and analysis is performed with the USEPA flux chamber.  The results are reported in 'odor emission factors' for the source tested.  Two common applications are shown in Photos 1 and 2, landfill odor assessment and compost site assessment, respectively.  Here odor samples are collected in Tedlar bags and shipped off to an odor lab (Odor Science and Technology or St. Croix Sensory) for analysis by one of two analytical methods: ASTM Method E-679 or EN 13725- both quantify olfactory odor as 'dilution to threshed' or DT units (like concentration).  These data are then used to diagnose odor sources on site, for engineering retrofit and odor abatement, or even input to dispersion models.  These odor emission factors are qualified by published test method, and most useful for predicting off-site odor impacts predicted as an 'odor level', typically ambient DT, which is directly comparable to odor measured in ambient air downwind of the site as determined by field measurement by a technique as a Nasal Ranger or an analytical method such as ASTM Method E-679 or EN 13725.

Recently, our team has been working with municipal agencies responsible for writing and enforcing odor codes.  One project included writing a detailed odor code for the enforcement branch of a city located in the Western states, which included a definition of an odor nuisance, acceptable ambient odor levels found on facility property lines, definition of a reportable complaint including odor level, frequency of odor event occurrence, and persistence of odor levels per odor episode.  This code was tailored to over ten types of facility or source including industrial/municipal (e.g., wastewater treatment, sewage collection, restaurants, marijuana grow and distribution, agricultural facilities, etc.) and residential sources (e.g., pet odors, waste storage, etc.).  We did this so that enforcement would be clearly defined per type or category of odor source, even including options for measurement and monitoring of olfactory odor and site-specific analytical methods for compounds associated with specific facilities or sources (e.g., hydrogen sulfide for sewage related sources).  The goal was to clearly define all aspects of a nuisance odor, protocols for assessment or enforcement, even documentation of the odor episodes for legally defensible enforcement files.  Note- An added benefit of the code and defined protocols is the protection of the municipality and the odor enforcement staff.  After writing the odor code for the municipality (actually two branches of the city- Enforcement Division and Public Works), we developed and presented a one-day workshop on the odor code and the enforcement of the odor code, including demonstrations of commonly used measurement (instrumental) and monitoring methods such as the use of the Nasal Ranger (Photo 3), sample collection in Tedlar bags using a decompression lung, screening with a Jerome hydrogen sulfide analyzer (Photo 4; J631X) and detection tubes.  An added benefit was an 'Odor Code Enforcement Handbook' for staff to use and refer to regarding enforcing the code, and tool that could be used for continued education for the municipality and orientation/training for new employees.  After reviewing dozens of odor codes across the nation, we have come to the conclusion that this odor code and enforcement protocol is the most thorough and comprehensive of its kind.  We would be most happy to assist you with your odor code development and odor code enforcement tasks.



Photo 1.  Assessing Odor Emissions from a Landfill

Assessing Odor Emissions from a Landfill



Photo 2.  Assessing Odor Emissions from a Compost Facility
Assessing Odor Emissions from a Compost Facility



Photo 3. St. Croix Sensory Nasal Ranger (Chuck McGinly shown)
nasal ranger



Photo 4. Screening for H2S Odors with a Jerome 631X Instrument




CE Schmidt, PhD, Environmental Consultant
19200 Live Oak Road, Red Bluff, California 96080
PHONE: (530) 529-4256 FAX: (530) 529-4878
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