# CRITERIA DOCUMENT: RECOMMENDATIONS FOR AN OCCUPATIONAL EXPOSURE STANDARD FOR METHYL ALCOHOL
Section 2 -Medical Medical surveillance shall be made available as specified below for all employees occupationally exposed to methyl alcohol.
(a) Preplacement medical examinations shall include:
(1) A comprehensive work history.
(2) A complete physical examination which should include an ophthalmologic examination.

# (b)
Medical surveillance and management including ophthalmologic examination shall be promptly provided to any employee who develops ocular symptoms, or has had methyl alcohol splashed in the eyes, or has ingested methyl alcohol, or has been accidentally overexposed by inhalation or dermal contact.
(c) Periodic medical surveillance should be performed annually for all employees occupationally exposed to methyl alcohol.    The employee should be reinformed at least once a year, or whenever there is a process change. This apprisal shall include, as a minimum, all information set forth in Appendix III which is applicable to that specific product or material containing methyl alcohol. For all work areas in which there is potential for emergencies, procedures as specified below, as well as any other procedures appropriate for a specific operation or process, shall be formulated in advance and employees shall be instructed in their implementation.
(1) Procedures shall include prearranged plans for obtaining emergency medical care and for necessary transportation of injured workers.
(2) Firefighting procedures shall be established and implemented. These shall include procedures for emergencies involving the release of methyl alcohol vapor. In case of fire, methyl alcohol sources shall be shut off or removed. Containers shall be removed or cooled with water spray. Chemical foam, carbon dioxide, or dry chemicals should be used for fighting methyl alcohol fires, and proper respiratory protection and protective clothing shall be worn.
(3) Approved eye, skin, and respiratory protection as specified in Section 4 shall be used by personnel essential to emergency operations.
(4) Nonessential employees shall be evacuated from exposure areas during emergencies. Perimeters of hazardous exposure areas shall be delineated, posted, and secured.
(5) Personnel properly trained in the procedures and adequately protected against the attendant hazards shall shut off sources of methyl alcohol, clean up spills, and immediately repair leaks. workdays of any change in production, process, or control that might result in an increase in airborne concentrations. When a fan is located in duct work and where methyl alcohol is likely to be present at concentrations at or above 0.67% (one-tenth the lower flammable limit, 67,000 ppm), the fan rotating element shall be of nonsparking material or the casting shall be coated with, or consist of, a nonsparking material. The ventilation system shall contain devices along the length of the exhaust system intended to prevent the propagation of flashbacks.

# (c) Loading and Unloading
The handling and storage of methyl alcohol shall comply with NFPA Article 30 for flammable and combustible liquids.
(1) Safety showers and eyewash fountains shall be installed in loading and unloading areas.
Fire extinguishers approved for Class I B fires, such as dry chemical extinguishers, shall be available in loading and unloading areas. Fire extinguishers shall be inspected annually and recharged or replaced if necessary.
(3) The equipment required by c(l) of this Section shall be inspected regularly to ensure that it is in working order. The employer shall ensure that such inspection is performed by a qualified person.
(4) In the event of a leak that may lead to airborne concentrations exceeding the environmental limits, the operations shall be stopped and resumed only after necessary repair or replacement has been completed.
(5) Bonding facilities for protection against static sparks during the loading of tank vehicles shall be provided as required in 29 CFR

# 1910.106(f)(3)(IV). (d) Methyl Alcohol Car and Truck Loading Procedure
(1) Smoking, matches, or lighters shall be prohibited in the methyl alcohol car and truck loading area.
The safety shower and eyewash fountain in the loading and unloading area shall be checked regularly.
(3) A wheel chock, a car loading sign, and the derail shall be placed in position and ground cables attached before connecting any lines to the tank car.
(4) Wheel chocks, ground cables, and loading sign shall be in place before connecting any lines to a trailer.
(5) Ground cables shall be removed only when loading or unloading lines have been removed and the dome covers have been secured.

# (h) General Housekeeping
Employers shall ensure that proper maintenance of equipment is provided in order to minimize the accidental escape of methyl alcohol.
Cleanup of spills and repair of equipment and leaks shall be performed as soon as practical.
(a)

# Food Facilities
In accordance with the provisions of 29 CFR 1910.141(g)( 2) and (g)(4), the consumption or storage of food or beverages shall be prohibited in the worksite.

# (b) Smoking
Smoking shall be prohibited in areas where methyl alcohol is used, transferred, stored, or manufactured.

# (c) Handwashing Facilities
Adequate facilities providing soap and water for handwashing shall be made available. In addition, they studied some of the chemical and physical properties of wood alcohol.
In 1855, MacFarlan  reported on the industrial utility of "methylated spirit" as a substitute for the higher priced, strictly regulated "spirit of wine" (ethyl alcohol). Methylated spirit was a mixture of "wood naphtha" (methyl alcohol) and "spirit of wine" (ethyl alcohol) usually in a proportion of 1 to 9, respectively. MacFarlan also noted the toxic hazard associated with the industrial use of pure methyl alcohol, "as opposed to methylated spirit," indicating that the former affected the eyes of workers while the vapor of the latter rarely did.
This constitutes one of the earliest references to the occupational hazard of methyl alcohol found in the literature.  The studies discussed in the remainder of this section are concerned with methyl alcohol absorption, elimination, and metabolism in the human.
The effect of ethyl alcohol on the metabolism and elimination of methyl alcohol and the explanation why ethyl alcohol administration is effective in preventing or ameliorating some of the symptoms of acute methyl alcohol intoxication in humans will also be examined.
In During the second 6-hour period after ethyl alcohol administration ceased, however, the formic acid excretion actually increased, presumably as a result of an uninhibited methyl alcohol oxidation process. Another significant conclusion of these authors was that the kidneys must have a considerable power of concentrating formate.    The results of the equimolar doses of the alcohols Indicated that the peroxidative system is not the primary metabolic pathway for methyl alcohol in the monkey. If it were so, inhibition of methyl alcohol oxidation should have been around 50%. These findings suggested that the alcohol dehydrogenase system, or possibly a system other than the peroxidative system, was responsible for methyl alcohol oxidation in the monkey.
In another study,  the effect of 1-butanol on 14C-methyl alcohol metabolism in the monkey was observed. In vitro studies cited by the authors showed that, compared with ethyl alcohol, the reactivity of 1butanol was greater for the alcohol dehydrogenase system. Moreover, 1butanol was less reactive with the perioxidase system than either ethyl or methyl alcohol. With a molar ratio of 14C-methyl alcohol to 1-butanol of 1:0.5, the oxidation of methyl alcohol was inhibited 63% during the first 90 minutes following dosing. This finding is in contrast to the results of the rat experiments described earlier  where 1-butanol did not noticeably affect methyl alcohol metabolism. This again supported the view that for monkeys the alcohol dehydrogenase, or some system not involving catalase, is the primary metabolic pathway for methyl alcohol oxidation. 
The     Chemical substances should be listed according to their complete name derived from a recognized system of nomenclature. Where possible, avoid using common names and general class names such as "aromatic amine," "safety solvent," or "aliphatic hydrocarbon" when the specific name is known.
The "%" may be the approximate percentage by weight or volume (indicate basis) which each hazardous ingredient of the mixture bears to the whole mixture. This may be indicated as a range or maximum amount, ie, "10-40% vol" or "10% max wt" to avoid disclosure of trade secrets.
Toxic hazard data shall be stated in terms of concentration, mode of exposure or test, and animal used, ie, "6.8 ml/kg LD50-oral-rat," "16.  to these oxidation products, should be attempted. The occurrence of similar ocular and neurotoxic effects would be supportive evidence that these effects of methyl alcohol in humans are so mediated.
The sampling procedure recommended in this document, while usable, has not been tested in conjunction with the recommended analytic method.
NIOSH is currently testing a modified gas chromatographic method (similar to that in this document) to be used in conjunction with the recommended sampling method.
In view of the demonstrated differences in metabolism of methyl alcohol between primates and lower animals, the utility of mutagenic, 127 teratogenic, or carcinogenic studies in rodents, often the species of choice for such studies, is not clear. Perhaps experimental exposures of rodents to the human metabolites of methyl alcohol would give useful information on these points.

# D E P A R T M E N T OF H E A L T H . E D U C A T IO N , A N D W E L F A R E PUBLIC H E A L T H SERVICE
Collect air samples from within the employee's breathing zone.

# (b)
Record the following on all sampling data sheets:
(1) Date and time of sample collection.
(2) Sampling duration.
(3) Volumetric flowrate of sampling.
(4) Description of sampling location.
(5) Serial number of pump.
(6) Name of person performing the calibration or sampling.
(7) Other pertinent information (temperature, pressure, and information listed in paragraph (i) of Calibration of Equipment) .

# Recommended Method
The sampling train consists of a silica gel tube and a vacuum pump.

# Range and Sensitivity
The sampling method is intended to provide a measure of airborne methyl alcohol in the range of 100-1,000 ppm. This method has been validated at methyl alcohol concentrations of 100, 200, and 400 ppm and a sampling time of 60 minutes, and at 1,000 ppm for at least a 15-minute sampling period.
The gas chromatographic method can measure from 1 to 40 (xg/ml of methyl alcohol in aqueous solutions.
 When used in combination, it is estimated that the sampling and analytic methods will determine as little as 0.8 ppm methyl alcohol in a 3-liter air sample. For aqueous solutions, the working range for methyl alcohol is linear up to concentrations of 40

# Hg/ml.
 However, the gas chromatographic method can easily be applied to higher concentrations by appropriate serial dilution of the desorbing solution with distilled water.

# Interferences
Any compound which has the same retention time as methyl alcohol at the operating conditions described in this method will interfere with the analysis.
The retention time of any substance suspected of being present in the sample should be determined to evaluate the likelihood of its interfering with the procedure.

# Precision and Accuracy
The