Page images
PDF
EPUB
[blocks in formation]
[blocks in formation]

Chemical of the month

4/C M. D. Bush

Isopropyl Alcohol

The chemical isopropyl alcohol (IPA) has the formula CH3CHOHCH3. It is also referred to as isopropanol, 2-propanol, di-methyl carbinol and petrohol, but is most commonly known as rubbing alcohol.

At room temperature, IPA is a clear liquid with a slight odor resembling that of an ethanol and acetone mixture. It is the 44th highest-volume chemical produced in the United States, and is commonly shipped in drums, tank trucks and railroad cars.

IPA has many uses other than for body rubbing. Like most alcohols, it is highly volatile and, therefore, used in quick-drying inks and oils, in anti-freeze compositions and as a solvent in gums and shellacs. A common denaturant for ethyl alcohol, it is found in hand lotions, after shave lotions and cosmetics. In addition, IPA is used in the production of acetone, glycerol and isopropyl acetate. Hazards

Although it does not react with water or any common materials, IPA, like all flammable liquids, should not be regarded as harmless. It is a grade C flammable liquid and has a NFPA hazard classification of three under the flammability category because of its relatively low flash point of 53°F. IPA's vapors may explode if ignited in an enclosed area and a flashback may occur along a vapor trail. Flammability limit in air reaches from a low of 2.3 percent to a high of 12 percent. If a fire occurs,

extinguish it with dry chemical, foam or carbon dioxide. (Water may not be effective.)

IPA has a slightly bitter taste, but is not at all potable. Although it is harmless to the skin, ingestion of 100 milligrams of IPA can be fatal. Inhalation of large quantities of the vapor can cause nausea, dizziness, vomiting, headache, coma, narcosis or mental depression.

A victim overcome by vapors should be immediately removed from exposure, and a physician should be called. Anyone who gets IPA in the eyes should flush them with water for at least 15 minutes.

Shipping

IPA is shipped in grades of 91 percent, 95 percent and 99 percent. Other than being flammable, the chemical presents no great shipping hazard. It is stable when stored at normal surrounding temperatures. Open ventilation or a pressure vacuum is required.

IMO considers IPA a non-pollutant, and has assigned it to appendix III of Annex II of MARPOL 73/78.

IPA does not react with most common construction materials. However, water solutions will react with aluminum, especially at elevated temperatures, and will cause rusting of mild steel. Shipping regulations require that a "flammable liquid" label be attached to any container of IPA.

Continued on page 38

[blocks in formation]

M. D. Bush was a fourth class cadet at the Coast Guard Academy when

this article was written as a special chemistry project for LCDR Thomas Chuba.

All data in this article was reviewed by the Hazardous Materials Branch of the Marine Technical and Hazardous Materials Division of the Coast Guard's Office of Marine Safety, Security and Environmental Protection. Telephone: (202) 267-1577.

Keynotes

March-April, 1992

Final rule correction

CGD 88-040, Benzene correction (46 CFR parts 30, 151, 153 and 197) RIN 2115-AD08 (December 13).

On October 17, 1991, the Coast Guard published a final rule in the Federal Register (56 FR 52122) revising the special carriage requirements for benzene and benzene mixtures, and adding new regulations limiting occupational exposure to benzene on Coast Guard-inspected vessels. This document corrects the final rule which will be effective January 15, 1992, by clarifying: (1) that the new rules do not require all U.S. flag vessels carrying liquid mixtures containing 0.5% to 10% benzene to comply with the requirements of 46 CFR 151 and 153; and (2) that the new rules do not apply to foreign flag vessels. This correction document also changes the effective dates for some of the monitoring and medical surveillance requirements.

EFFECTIVE DATE: January 15, 1992.

For further information, contact: Dr. Alan L. Schneider, Hazardous Materials Branch, Office of Marine Safety, Security and Environmental Protection, (202) 267-1217.

Notice of proposed rule

CGD 91-030, Direct user fees for inspection or examination of U.S. and foreign commercial vessels (33 CFR part 143, 46 CFR part 2) RIN 2115-AD78 (December 18).

The Omnibus Budget Reconciliation Act of 1990 requires the Coast Guard to establish user fees for services related to the inspection and examination of U.S. and foreign vessels, and issuance of Certificates of Inspection, Certificates of Compliance, and related documents. The proposed fees are based on the way the Coast Guard presently conducts vessel inspection activities. This proposal is intended to recover costs of providing certain vessel inspection services.

DATE: Comments must have been received by February 18, 1992.

For further information, contact: CDR Bruce A. Russell, Chief, Plans and Analysis Branch (GMP-1), Office of Marine Safety, Security and Environmental Protection, (202) 267-6923.

Notice of proposed rule correction

Appendix A was omitted from the notice of proposed rule concerning direct user fees (above) when published in the Federal Register on December 18, 1991. This appendix appears in full in the December 24, 1991, issue of the Federal Register on page 66766.

For further information, contact: CDR Bruce A. Russell, Chief, Plans and Analysis Branch (GMP-1), Office of Marine Safety, Security and Environmental Protection, (202) 267-6923.

Notice of proposed rule

CGD 91-204, Use of automatic pilot: area restrictions and performance requirements (46 CFR part 35) RIN 2115-AE00 (January 6).

The Coast Guard proposes to implement a provision of section 4114(a) of the Oil Pollution Act of 1990 (OPA 90), by defining the conditions under which, and designating the waters where, tank vessels may operate with the automatic pilot engaged. This proposed rulemaking will promote the safe operation of tank vessels in U.S. waters. Section 4114(a) also requires restrictions on operations of tank vessels with unattended machinery spaces. Regulations restricting operations with unattended machinery spaces are the subject of a separate rulemaking.

DATE: Comments must be received on or before March 6, 1992.

Continued on page 40

« PreviousContinue »