Odor safety factor

The sense of smell can sometimes be of use in ascertaining that the TLV of a hazardous substance has been exceeded before it is too late. J.E. Amoore and E. Hautala (Journal of Applied ToxicologyS, No. 6 (1983) 272ff) have developed an Odor Safety Factor classification with five categories the have also compiled a list of mean odor limits for 214 volatile substances based on various sources. These limits indicate the atmospheric concentration at which 50% of the test subjects, having been given prior warning, were just able to identify the odor. 

Thus the OSF Is 1 when a concentration equal to the TLV-value is detected by 50% of the subjects. 

Amoore and Hautala also investigated the effects of distraction (e.g. by work-related tasks) on odor Identification and discovered that, under these conditions, the OSF reached 26 before 50% of subjects detected that the TLV had been attained. In the case of subjects given prior warning, 99% could detect attainment of the TLV at OSF=26. 

A 550 More than 90% of exposed persons able to detect attainment of TLV by smell, even when distracted by work environment 

C 1-26 Less than 50% of the distracted subjects able to detect 

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Health and Safety Factors. The following toxicides for acetonitrile have been reported oral LD q (lats), 3030—6500 mg/kg skin LD q (rabbits), 3884—7850 mg/kg and inhalation LC q (i ts), 7500—17,000 ppm (29). Humans can detect the odor of acetonitrile at 40 ppm. Exposure for 4 h at up to 80 ppm has not produced adverse effects. However, exposure for 4 h at 160 ppm results in reddening of the face and some temporary bronchial tightness. 

The odor threshold for most atmospheric pollutants may be found in the literature (1). By properly applying the diffusion equations, one can calculate the height of a stack necessary to reduce the odor to less than its threshold at the ground or at a nearby structure. A safety factor of two orders of magnitude is suggested if the odorant is particularly objectionable. 

HeaUh and Safety Factors. The 2-cyanoacrylic esters have sharp, pungent odors and arc lacrimators. even at very low concentrations. The TLV for methyl 2-eyanoacrylate is 2 ppm and the sliort-tenii exposure limit is 4 ppm. Good ventilation when using the adhesives is essential. 

Health and Safety Factors. Mesityl oxide is more toxic than saturated ketones and is highly irritating to all tissues on vapor or liquid contact and for this reason sales of mesityl oxide ceased in the United States in 1986. It is absorbed through intact skin, and prolonged exposure can damage liver, kidneys, and lungs. Repeated exposure to vapors can cause anemia and leukopenia (187) however, the odor is so intolerable that long-term exposure is unlikely. Mesityl oxide is still produced, but is consumed captively as an intermediate in the production of MIBK, methyl isobutyl carbinol, and isophorone. 

One of hydrogen sulfide s most readily recognized properties is its odor, which is most frequently encountered as the offensive odor of rotten e s. Hydrogen sulfide is toxic but our noses can detect H2S in extremely low, nontoxic concentrations. A sulfur-containing organic molecule, such as dimethyl sulfide, (CH3)2S, which is similarly odoriferous and can be detected by smell at a level of one part per trillion, is added to natural gas as a safety factor to give it a detectable odor. 

The industrial hygiene data collected demonstrated that there were no detrimental human, health or safety factors associated with the storage or handling of the tire chips at the plant. There were no noticeable odors from the tire chips, either inside or outside the plant, and the results of testing indicated there were no significant worker hazards associated with tire chip burning when compared to burning coal alone. 

Chemical selection depends on many factors. These factors include the treatment objective, the quality and variability of the untreated water, chemical availability, delivery time, suitable storage, feed equipment and accuracy, safety considerations, cost, and employee training. The treatment objective is perhaps the most important factor in chemical selection. A treatment objective might include reduction of lead levels in customers homes with a corrosion inhibitor, elimination of taste and odor compounds with ozone, or maintenance of a chlorine residual at the farthest end of the system. 

The causes of flow-related problems include faulty connections between units and total or partial interconnection failure. In the case of fluids, the factors that must be considered with care from the safety perspective include flammability, loss of pressure, toxicity, lubricity, contamination, and odor. 

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