ACGIH Threshold Limit Values

Material Safety Data Sheets (MSDS) issued by suppHers of acetone ate requited to be revised within 90 days to include new permissible exposure limits (PEL). Current OSHA PEL (54) and ACGIH threshold limit values (TLV) (55) ate the same, 750 ppm TWA and 1000 ppm STEL. Eot comparison, the ACGIH TWA values for the common mbbing alcohols are ethyl, 1000, and isopropyl, 400 ppm. A report on human experience (56) concluded that exposure to 1000 ppm for an 8-h day produced no effects other than slight, transient irritation of the eyes, nose, and throat. 

American Conference of Government Industrial Hygienists (ACGIH) threshold limit value = 5 ppm on an 8-h time-weighted average. 

Maleic Anhydride. The ACGIH threshold limit value in air for maleic anhydride is 0.25 ppm and the OSHA permissible exposure level (PEL) is also 0.25 ppm (181). Maleic anhydride is a corrosive irritant to eyes, skin, and mucous membranes. Pulmonary edema (collection of fluid in the lungs) can result from airborne exposure. Skin contact should be avoided by the use of mbber gloves. Dust respirators should be used when maleic anhydride dust is present. Maleic anhydride is combustible when exposed to heat or flame and can react vigorously on contact with oxidizers. The material reacts exothermically with water or steam. Violent decompositions of maleic anhydride can be catalyzed at high temperature by strong bases (sodium hydroxide, potassium hydroxide, calcium hydroxide, alkaU metals, and amines). Precaution should be taken during the manufacture and use of maleic anhydride to minimize the presence of basic materials. 

Potassium alum, which also occurs naturally as the mineral kalinite [7784-24-9], KAl(SO 2 12H20, sp gr 1.75, is used ia tanning skins, as a mordant ia dyeiag, and ia the pharmaceutical and cosmetic iadustries (see Pharmaceuticals Cosmetics). It is used as a styptic pencil and as a hardening agent and set accelerator for cement and plaster. The ACGIH threshold limit value TWA is 2 mgAl/m (1 ). 

Use of isopropyl alcohol in industrial appHcations does not present a health hazard. The alcohol produces anesthetic effects in high vapor concentration. Consequently, the OSHA permissible exposure limit (PEL) and the ACGIH threshold limit value (TLV) have been estabUshed at 400 ppm (0.098 mg/L) for an 8-h exposure (TWA) (138). This level causes a mild irritation of the eyes, nose, and throat (139). However, the TLV level does not produce symptoms of anesthesia (140). The OSHA and ACGIH short-term exposure limits (STELs) are 500 ppm. The odor threshold for isopropyl alcohol ranges from 3 to 200 ppm, which is the minimum concentration having identifiable odor (141). 

The ACGIH threshold limit value (TLV), time-weighted average for an 8 hour workday, 40 hour workweek, was set at 50 ppm (- 200 mg/m ) with a notation for skin absorption (29). 

The time-weighted average OSHA permissible exposure limit (PEL), as weU as the ACGIH threshold limit value (TLV), for cyclohexanone is 25... 

ACGIH. Threshold limit values for chemical substances and physical agents and biological exposure indices. Cincinnati, 1 992. 

Chemical and common names of all ingredients determined to be healtli liazards mid comprising less than 1 percent (0.1 percent for carcinogens) of tlie mi.xlure must also be listed if they can still exceed an established OSHA Permissible Exposure Limit (PEL) or tlic ACGIH Threshold Limit Value (TLV) or present a health risk to exposed employees in tlicsc concentrations. The next chapter will address PELs and TLVs in further detail. 

There are three biological exposure indices (BEls) for exposure to trichloroethylene at the ACGIH threshold limit value time-weighted average (TLV-TWA) of 50 ppm (ACGIH 1996). When measured at the end of a 40-hour workweek, TCA in urine is approximately 100 mg/g creatinine when measured at the end of an 8-hour shift at the end of a workweek TCA and trichloroethanol in urine is approximately 300 mg/g creatinine, and free trichloroethanol in blood is approximately 4 mg/L. 

Certain (ACGIH) criteria may be appropriate for use as benchmarks. The ACGIH threshold limit values — TLV-STELs and TLV-Cs — are designed to protect workers from acute effects resulting from exposure to chemicals such effects include irritation and narcosis. These criteria are discussed in chapter 2. These criteria can be used for toxic gas dispersion but typically produce a conservative result because they are designed for worker exposures. 

Guidelines a. Air ACGIH Threshold Limit Values for Occupational Exposure (TLV-TWA) Cyanogen TLV - Ceiling Hydrogen cyanide, sodium cyanide, calcium cyanide, potassium cyanide, acetone cyanohydrin Cyanogen chloride 21 mg/m3 5 mg/m3 0.75 mg/m3 ACGIH 1996... 

Acetic acid was not clastogenic in Chinese hamster ovary (CHO) cells in vitro when the pH of the culture medium was neutralized. The 2003 ACGIH threshold limit value-time-weighted average (TLV-TWA) for acetic acid is 10 ppm (25mg/m ) with a short-term exposure limit of 15 ppm (37mg/m ). 

The 2003 ACGIH threshold limit value-time-weighted average (TLV-TWA) for aluminum oxide is lOmg/m for total dust containing no asbestos and <1% crystalline silica. 

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