What is the threshold of smell?
Odor threshold is the minimum concentration of a substance at which a majority of test subjects can detect and identify the characteristic odor of a substance. While odor thresholds can serve as useful warning properties, they must be used cautiously because olfactory perception varies among individuals.
How is odor threshold determined?
The odor detection threshold is the lowest concentration of a certain odor compound that is perceivable by the human sense of smell. The threshold of a chemical compound is determined in part by its shape, polarity, partial charges, and molecular mass. As such, odor thresholds cannot be accurately predicted.
What is the odor threshold for methyl mercaptan?
An odor threshold of 0.002 ppm has been reported for methyl mercaptan, but olfactory fatigue may occur and thus, it may not provide adequate warning of hazardous concentrations. Vapors of liquified methyl mercaptan gas are heavier than air and spread along the ground.
How many ppm can a human smell?
OSHA says the Odor Threshold is between 5 and 50 ppm. Although most organizations agree that most people can smell ammonia somewhere around 5 ppm, there is some evidence that people can lose their ability to detect ammonia after working around it for a while.
At what ppm can you smell ammonia?
5 ppm
The odor of ammonia can be detected by humans at concentrations >5 ppm; the odor is highly penetrating at 50 ppm (10 min).
What is recognition threshold?
the shortest exposure to a stimulus at which recognition of that stimulus can occur. The shortest exposure at which words, for example, will be recognized is typically between 10 and 40 ms.
What ppm can you smell ammonia?
The Odor Threshold for ammonia has been documented in different studies as low as . 04 ppm and as high as 57 ppm. The American Association of Railroads says most people can smell ammonia between 0.04 to 20 ppm. OSHA says the Odor Threshold is between 5 and 50 ppm.
What is the formula of ethyl mercaptan?
C₂H₆S
Ethanethiol/Formula
What is the odor threshold for hydrogen sulfide?
Health Hazards
| Concentration (ppm) | Symptoms/Effects |
|---|---|
| 0.00011-0.00033 | Typical background concentrations |
| 0.01-1.5 | Odor threshold (when rotten egg smell is first noticeable to some). Odor becomes more offensive at 3-5 ppm. Above 30 ppm, odor described as sweet or sickeningly sweet. |
At what ppm can you smell natural gas?
10 ppm
The gas has a smell at an odor threshold of 1 ppb, and OSHA has a Permissible Exposure Limit for mercaptan of 10 ppm. See more in the FAQ in About Gas Odorization.
Is ethyl acrylate safe to use?
One favorable safety aspect is that ethyl acrylate has good warning properties; the odor threshold is much lower than any level of health concern. In other words, the bad odor warns people of ethyl acrylate’s presence long before the concentration reaches a level capable of creating a serious health risk.
What is the detection threshold of acetic acid?
The detection threshold, the concentration at which there is 75% correct detection, was determined using least-squares linear regression. The correlation coefficients for the linear regressions for acetic acid and ethyl acetate were r = 0.996 (p < 0.001) and r = 0.972 (p < 0.001), respectively.
What is the threshold for acetic acid in wine?
The thresholds for acetic acid and ethyl acetate were 3.185 and 0.198 g/l, respectively. The threshold for acetic acid was approximately three times that found in table wines, but was relatively unchanged for ethyl acetate.
What is the chemical formula for ethyl acrylate?
Ethyl acrylate is an organic compound with the formula CH 2CHCO 2CH 2CH 3. It is the ethyl ester of acrylic acid.