Newsletter
RSS Feeds
Print This Page
Text Size<< Back to Occupational Safety and Health Guidelines
This guideline summarizes pertinent information about zirconium and zirconium compounds (measured as zirconium) for workers and employers as well as for physicians, industrial hygienists, and other occupational safety and health professionals who may need such information to conduct effective occupational safety and health programs. Recommendations may be superseded by new developments in these fields; readers are therefore advised to regard these recommendations as general guidelines and to determine periodically whether new information is available.
This guideline applies to zirconium and to zirconium compounds. Examples of some zirconium compounds are zirconium acetate, zirconium boride, zirconium carbide, zirconium carbonate, zirconium disulfide, zirconium glycolate, zirconium hydride, zirconium hydroxide, zirconium nitrate, zirconium oxide, zirconium oxychloride, zirconium phosphate, zirconium sulfate, zirconium tetrachloride, and zirconyl acetate. For illustrative purposes, the physical and chemical properties of zirconium and of several zirconium compounds are presented below.
Zirconium SUBSTANCE IDENTIFICATION * Formula Zr* Structure (For Structure, see paper copy)* Synonyms Zircat, zirconium metal* Identifiers 1. CAS 7440-67-7* Appearance and odor Zirconium is a grayish-white, lustrous, odorless metal; when powdered, it is bluish black. It is available commercially in powder, sponge, plate, strip, bar, wire, briquette, and foil forms.CHEMICAL AND PHYSICAL PROPERTIES * Physical data 1. Atomic number: 40Zirconium oxide SUBSTANCE IDENTIFICATION * Formula ZrO(2)* Structure (For Structure, see paper copy)* Synonyms Zirconia, zirconium dioxide, zirconium anhydride, zirconic anhydride* Identifiers 1. CAS 1314-23-4* Appearance and odor Zirconium oxide is a heavy, white, odorless powder.CHEMICAL AND PHYSICAL PROPERTIES * Physical data 1. Molecular weight: 123.2Zirconium oxychloride SUBSTANCE IDENTIFICATION * Formula ZrOCl(2)*8H(2)O* Structure (For Structure, see paper copy)* Synonyms Zirconyl chloride, zirconyl chloride octahydrate, zirconium oxide chloride, chlorozirconyl, dichlorooxozirconium* Identifiers 1. CAS 7699-43-6* Appearance and odor Zirconium oxychloride is an odorless, yellow to white solid.CHEMICAL AND PHYSICAL PROPERTIES * Physical data 1. Molecular weight: 322.3Zirconium tetrachloride SUBSTANCE IDENTIFICATION * Formula ZrCl(4)* Structure (For Structure, see paper copy)* Synonyms Zirconium chloride* Identifiers 1. CAS 10026-11-6* Appearance and odor Zirconium tetrachloride is a noncombustible, white, lustrous solid that has an acrid odor in moist air.CHEMICAL AND PHYSICAL PROPERTIES * Physical data 1. Molecular weight: 233Zirconium hydride SUBSTANCE IDENTIFICATION * Formula ZrH(2)* Structure (For Structure, see paper copy)* Synonyms Zirconium dihydride* Identifiers 1. CAS 7704-99-6* Appearance and odor Zirconium hydride is a flammable, odorless, dark grey to black, metallic powder.CHEMICAL AND PHYSICAL PROPERTIES * Physical data 1. Molecular weight: 93.2Zirconyl acetate SUBSTANCE IDENTIFICATION * Formula Zr(OH)(2)(C(2)H(3)O(2))(2)* Structure (For Structure, see paper copy)* Synonyms Diacetatozirconic acid; bis(acetato-o,o')oxo-zirconium* Identifiers 1. CAS 20645-04-9* Appearance and odor Zirconyl acetate is a colorless, tacky, resinous, amorphous solid.CHEMICAL AND PHYSICAL PROPERTIES * Physical data 1. Molecular weight: 225.3* Reactivity 1. Conditions contributing to instability vary with the form of zirconium or with the specific zirconium compound. Powdered zirconium and zirconium borings and shavings are highly flammable and may ignite spontaneously in air. In contact with water, zirconium tetrachloride reacts vigorously to form hydrogen chloride; this substance also ignites spontaneously in air. Zirconium hydride is a flammable solid; in powdered form, it can ignite and explode if exposed to heat, fire, or sparks.* Flammability The National Fire Protection Association (NFPA) has assigned a flammability rating of 4 (extreme fire hazard) to zirconium in powdered form. Zirconium hydride's fire hazard is rated by another source as slight [Genium MSDS 1987, No. 212], and neither zirconium oxide nor zirconium tetrachloride is flammable. No information is available on the flammability of the other zirconium compounds highlighted in this guideline.1. Flash point: Not applicable 2. Autoignition temperature: For zirconium, the autoignition temperature varies with particle size: for 18-m particles, it is approximately 350 degrees C (662 degrees F); however, 3-m particles are reported to have a high autoignition potential. For zirconium hydride, the autoignition temperature is 270 degrees C (518 degrees F). 3. Flammable limits in air: Not applicable 4. Extinguishant: For a fire involving zirconium powder, do NOT use water, carbon dioxide, halocarbon, or soda ash extinguishants; use dry sand, Fuller's earth, or a proprietary metal fire extinguishant. For a fire involving zirconium hydride, do NOT use water, carbon dioxide, or halocarbon-based extinguishing agents; use powdered limestone (dolomite), dry sand, graphite powder, or a proprietary metal fire extinguishant. For a fire involving zirconium oxide or zirconium tetrachloride, use an extinguishant that is suitable for the material involved in the surrounding fire. Fires involving zirconium or zirconium compounds should be fought upwind and from the maximum distance possible. Keep unnecessary people away; isolate hazard area and deny entry. Emergency personnel should stay out of low areas and ventilate closed spaces before entering. Explosion hazards may occur indoors, outdoors, or in sewers. Containers of powdered zirconium or zirconium compounds may explode in the heat of the fire and should be moved from the fire area if it is possible to do so safely. If this is not possible, cool containers from the sides with water until well after the fire is out. Stay away from the ends of containers. Personnel should withdraw immediately if a rising sound from a venting safety device is heard or if there is discoloration of a container due to fire. Dikes should be used to contain fire-control water for later disposal. If a tank car or truck is involved in a fire, personnel should isolate an area of a half a mile in all directions. Firefighters should wear a full set of protective clothing, including a self-contained breathing apparatus, when fighting fires involving powdered zirconium or a flammable or combustible zirconium compound.* Warning properties Zirconium and most zirconium compounds are odorless; these substances are therefore considered to have inadequate odor warning properties.* Eye irritation properties No quantitative data are available on the eye irritation threshold for zirconium or zirconium compounds; however, these substances are not known to be eye irritants.EXPOSURE LIMITS The current Occupational Safety and Health Administration (OSHA) permissible exposure limits (PELs) for zirconium and zirconium compounds (measured as zirconium) are 5 milligrams per cubic meter (mg/m(3)) of air as an 8-hour time-weighted average (TWA) concentration and 10 mg/m(3) as a 15-minute TWA short-term exposure limit (STEL). A STEL is the maximum 15-minute concentration to which workers may be exposed during any 15-minute period of the working day [29 CFR 1910.1000, Table Z-1-A]. The National Institute for Occupational Safety and Health (NIOSH) has not issued a recommended exposure limit (REL) for zirconium and zirconium compounds. The American Conference of Governmental Industrial Hygienists (ACGIH) has assigned zirconium and zirconium compounds (measured as zirconium) threshold limit values (TLVs) of 5 mg/m(3) as a TWA for a normal 8-hour workday and a 40-hour workweek and a short-term exposure limit (STEL) of 10 mg/m(3) for periods not to exceed 15 minutes [ACGIH 1988, p. 43]. The OSHA and ACGIH limits are based on the risk of pulmonary effects associated with exposure to zirconium or its compounds.
HEALTH HAZARD INFORMATION * Routes of Exposure Exposure to zirconium and zirconium compounds can occur via inhalation, ingestion, and eye or skin contact.* Summary of toxicology 1. Effects on Animals: Inhalation of the dust of zirconium compounds has caused pulmonary granulomas in experimental animals. The oral LD(50)s for zirconium compounds range from 1.7 to 10 g/kg, depending on the compound [Proctor, Hughes, and Fischman 1988, p. 517]. In rats, the intraperitoneal LD(50) for zirconyl acetate is 400 mg/kg, while the oral LD(50) for the same substance is 4100 mg/kg [RTECS 1989c; Clayton and Clayton 1981, p. 2054]; the intraperitoneal toxicity both of the inorganic and organic compounds of zirconium is approximately 20 times greater than their oral toxicity [Clayton and Clayton 1981, p. 2054]. Animals acutely poisoned with zirconium show progressive depression and decreasing activity before death [Clayton and Clayton 1981, p. 2054]. Exposure to zirconium lactate or barium zirconate at airborne concentrations greater than 5 mg/m(3) produced severe, chronic, interstitial pneumonitis in laboratory animals [Parmeggiani 1983, p. 2343]. Daily 20-minute inhalation exposures to an unspecified concentration of the mist of sodium zirconium lactate for 6 weeks produced bronchial abscesses (with lobar pneumonia) or peribronchial granulomas in rabbits [Clayton and Clayton 1981, p. 2055]. Intensive (not further specified) exposure of rats to the dust of zirconium silicate for 7.5 months produced shadows on the lungs radiographically, but no histologic changes were seen in these animals at autopsy [Clayton and Clayton 1981, p. 2955]. Several inhalation studies involving animals of different species and exposure for 1 year either to zirconium oxide dust or zirconium tetrachloride mist (at a zirconium concentration of 3.5 mg/m(3)) measured mortality, weight changes, hematologic parameters, and urinary protein and found only slight decreases in hemoglobin and erythrocyte count in dogs exposed to high (6 mg/m(3) zirconium) concentrations of zirconium tetrachloride; no histological changes were seen in these animals at autopsy [ACGIH 1986, p. 647].* Signs and symptoms of exposure 1. Acute exposure: The signs and symptoms of skin contact with zirconium compounds include small, reddish-brown papules in linear streaks on the abraded skin.* Emergency procedures: In the event of an emergency, remove the victim from further exposure, send for medical assistance, and initiate the following emergency procedures: 1. Eye exposure: If zirconium or a zirconium compound gets into the eyes, immediately flush the eyes with large amounts of water for a minimum of 15 minutes, lifting the lower and upper lids occasionally. If irritation persists, get medical attention as soon as possible.EXPOSURE SOURCES AND CONTROL METHODS The following operations may involve zirconium and zirconium compounds and lead to worker exposures to this substance: Zirconium:
1. ACGIH [1986]. Industrial ventilation--a manual of recommended practice. Cincinnati, OH: American Conference of Governmental Industrial Hygienists. 2. Burton DJ [1986]. Industrial ventilation--a self study companion. Cincinnati, OH: American Conference of Governmental Industrial Hygienists. 3. Alden JL, Kane JM [1982]. Design of industrial ventilation systems. New York, NY: Industrial Press, Inc. 4. Wadden RA, Scheff PA [1987]. Engineering design for control of workplace hazards. New York, NY: McGraw-Hill. 5. Plog BA [1988]. Fundamentals of industrial hygiene. Chicago, IL: National Safety Council. MEDICAL MONITORING Workers who may be exposed to chemical hazards should be monitored in a systematic program of medical surveillance that is intended to prevent occupational injury and disease. The program should include education of employers and workers about work-related hazards, placement of workers in jobs that do not jeopardize their safety or health, early detection of adverse health effects, and referral of workers for diagnosis and treatment. The occurrence of disease or other work-related adverse health effects should prompt immediate evaluation of primary preventive measures (e.g., industrial hygiene monitoring, engineering controls, and personal protective equipment). A medical monitoring program is intended to supplement, not replace, such measures. To place workers effectively and to detect and control work-related health effects, medical evaluations should be performed (1) before job placement, (2) periodically during the period of employment, and (3) at the time of job transfer or termination. * Preplacement medical evaluation Before a worker is placed in a job with a potential for exposure to zirconium or a zirconium compound, the examining physician should evaluate and document the worker's baseline health status with thorough medical, environmental, and occupational histories, a physical examination, and physiologic and laboratory tests appropriate for the anticipated occupational risks. These should concentrate on the function and integrity of the respiratory system and skin. Medical monitoring for respiratory disease should be conducted using the principles and methods recommended by NIOSH and the American Thoracic Society.* Periodic medical examinations and biological monitoring Occupational health interviews and physical examinations should be performed at regular intervals during the employment period, as mandated by any applicable Federal, State, or local standard. Where no standard exists and the hazard is minimal, evaluations should be conducted every 3 to 5 years or as frequently as recommended by an experienced occupational health physician. Additional examinations may be necessary if a worker develops symptoms attributable to exposure to zirconium or a zirconium compound. The interviews, examinations, and medical screening tests should focus on identifying the adverse effects of zirconium and zirconium compounds on the respiratory system or skin. Current health status should be compared with the baseline health status of the individual worker or with expected values for a suitable reference population.* Medical examinations recommended at the time of job transfer or termination The medical, environmental, and occupational history interviews, the physical examination, and selected physiologic or laboratory tests that were conducted at the time of placement should be repeated at the time of job transfer or termination to determine the worker's medical status at the end of his or her employment. Any changes in the worker's health status should be compared with those expected for a suitable reference population.WORKPLACE MONITORING AND MEASUREMENT PROCEDURES Determination of a worker's exposure to airborne zirconium or a zirconium compound (measured as zirconium) is made using a tared low ash polyvinyl chloride filter (5 microns). Samples are collected at a maximum flow rate of 2 liters per minute until a maximum air volume of 960 liters is collected. The sample is then analyzed gravimetrically. This method has a sampling and analytical error of 0.01 and is included in the OSHA Computerized Information System [OSHA 1985] and the OSHA Chemical Information Manual [OSHA 1987]. NIOSH has a sampling and analytical method for zirconium compounds (measured as zirconium) that involves filter collection, acid digestion, and atomic absorption spectrophotometric analysis and is described in Method S185 of the NIOSH Manual of Analytical Methods, 2nd edition, Volume 3 [NIOSH 1977].
PERSONAL HYGIENE PROCEDURES If zirconium or a zirconium compound contacts the skin, workers should immediately wash the affected areas with soap and water. Clothing contaminated with zirconium or a zirconium compound should be removed immediately, and provisions should be made for the safe removal of the chemical from the clothing. Persons laundering the clothes should be informed of the hazardous properties of zirconium and zirconium compounds, particularly their potential to cause irritation of the skin. A worker who handles zirconium or a zirconium compound should thoroughly wash hands, forearms, and face with soap and water before eating, using tobacco products, or using toilet facilities. Workers should not eat, drink, or use tobacco products in areas where zirconium or a zirconium compound is handled, processed, or stored. STORAGE Zirconium or zirconium compounds should be stored in a cool, dry, well-ventilated area in tightly sealed containers that are labeled in accordance with OSHA's Hazard Communication Standard [29 CFR 1910.1200]. Dry powdered zirconium is ignitable at room temperature by static electricity or simple friction and should therefore be stored under a dry argon atmosphere. Powdered zirconium or zirconium hydride should be handled either in a dry, inert atmosphere or under water. Containers of powdered zirconium should be examined regularly for signs of rust or moisture. All lines and equipment used near powdered zirconium or zirconium hydride must be bonded and grounded, and all tools used with these substances must be nonsparking. A supply of powdered limestone, dry sand, Fuller's earth, or a metal extinguishant must be kept readily available to extinguish fires involving these substances. Containers of zirconium or a zirconium compound should be protected from physical damage and be separated from incompatible chemicals, water or moisture, heat, sparks, and open flame. Because empty containers that formerly contained zirconium or a zirconium compound may contain product residues, they should be handled appropriately. SPILLS AND LEAKS In the event of a spill or leak involving zirconium or a zirconium compound, persons not wearing protective equipment and clothing should be restricted from contaminated areas until cleanup has been completed. The following steps should be undertaken following a spill or leak: 1. Do not touch the spilled material. 2. Notify safety personnel. 3. Remove all sources of heat and ignition. 4. Ventilate potentially explosive atmospheres. 5. Use cleanup methods that minimize the generation of dust. 6. Only nonsparking tools may be used to clean up powdered zirconium, zirconium hydride, or other flammable zirconium compounds. 7. Spills of powdered zirconium must be kept wet at all times to avoid ignition and must be collected and stored under water in a metal drum for later disposal. 8. Zirconium hydride spills should be covered with limestone before being cleaned up; use a clean shovel and place the material into a clean, dry container; cover and remove the container from the spill area. EMERGENCY PLANNING, COMMUNITY RIGHT-TO-KNOW, AND HAZARDOUS WASTE MANAGEMENT REQUIREMENTS The Environmental Protection Agency's (EPA's) regulatory requirements for emergency planning, community right-to-know, and hazardous waste management may vary over time. Users are therefore advised to determine periodically whether new information is available. * Emergency planning requirements Zirconium and zirconium compounds are not subject to EPA emergency planning requirements under the Superfund Amendments and Reauthorization Act (Title III).* Reportable quantity requirements for hazardous releases Employers are not required by the emergency release notification provisions of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) [40 CFR Part 355.40] to notify the National Response Center of an accidental release of zirconium or a zirconium compound; there is no reportable quantity for these substances.* Community right-to-know requirements Employers are not required by Section 313 of the Superfund Amendments and Reauthorization Act (SARA) to submit a Toxic Chemical Release Inventory form (Form R) to EPA reporting the amount of zirconium or zirconium compounds emitted or released from each facility annually.* Hazardous waste management requirements EPA considers a waste to be hazardous if it exhibits any of the following characteristics: ignitability, corrosivity, reactivity, or toxicity, as defined in 40 CFR 261.21-261.24. Under the Resource Conservation and Recovery Act (RCRA), EPA has specifically listed many chemical wastes as hazardous. Although zirconium and its compounds are not specifically listed as a hazardous waste under RCRA, EPA requires employers to treat any waste as hazardous if it exhibits any of the characteristics discussed above.RESPIRATORY PROTECTION * Conditions for respirator use Good industrial hygiene practice requires that engineering controls be used where feasible to reduce workplace concentrations of hazardous materials to the prescribed exposure limit. However, some situations may require the use of respirators to control exposure. Respirators must be worn if the ambient concentration of zirconium or a zirconium compound exceeds prescribed exposure limits. Respirators may be used (1) before engineering controls have been installed, (2) during work operations such as maintenance or repair activities that involve unknown exposures, (3) during operations that require entry into tanks or closed vessels, and (4) during emergency situations. If the use of respirators is necessary, the only respirators permitted are those that have been approved by NIOSH and the Mine Safety and Health Administration (MSHA).* Respiratory protection program Employers should institute a complete respiratory protection program that, at a minimum, complies with the requirements of OSHA's Respiratory Protection Standard [29 CFR 1910.134]. Such a program must include respirator selection (see Table 1), an evaluation of the worker's ability to perform the work while wearing a respirator, the regular training of personnel, fit testing, periodic workplace monitoring, and regular respirator maintenance, inspection, and cleaning. The implementation of an adequate respiratory protection program (including selection of the correct respirator) requires that a knowledgeable person be in charge of the program and that the program be evaluated regularly. For additional information on the selection and use of respirators and on the medical screening of respirator users, consult the NIOSH Respirator Decision Logic [NIOSH 1987c] and the NIOSH Guide to Industrial Respiratory Protection [NIOSH 1987a].PERSONAL PROTECTIVE EQUIPMENT Protective clothing should be worn to prevent skin contact with zirconium or a zirconium compound. Flame-resistant gloves and chemical- and flame-resistant protective clothing (aprons, coveralls, etc.) are recommended when workers handle powdered zirconium, zirconium hydride, or other flammable zirconium compounds. Chemical protective clothing should be selected on the basis of available performance data, manufacturers' recommendations, and evaluation of the clothing under actual conditions of use. No reports have been published on the resistance of various protective clothing materials to permeation by zirconium or a zirconium compound. If permeability data are not readily available, protective clothing manufacturers should be requested to provide information on the best chemical protective clothing for workers to wear when they are exposed to zirconium or a zirconium compound. If zirconium or a zirconium compound is dissolved in water or an organic solvent, the permeation properties of both the solvent and the mixture must be considered when selecting personal protective equipment and clothing. Safety glasses, goggles, or faceshields should be worn during operations in which zirconium or a zirconium compound might contact the eyes (e.g., through dust particles or splashes of solution). Eyewash fountains and emergency showers should be available within the immediate work area whenever the potential exists for eye or skin contact with zirconium or a zirconium compound. Contact lenses should not be worn if the potential exists for exposure to any of these substances.
ACGIH [1988]. TLVs. Threshold limit values and biological exposure indices for 1988-1989. Cincinnati, OH: American Conference of Governmental Industrial Hygienists. Clayton G, Clayton F [1981]. Patty's industrial hygiene and toxicology. 3rd revised edition. New York, NY: John Wiley & Sons. Code of Federal regulations. Washington, DC: U.S. Government Printing Office, Office of the Federal Register. Gosselin RE, Smith RP, Hodge HC [1984]. Clinical toxicology of commercial products. 5th edition. Baltimore, MD: Williams & Wilkins. NIOSH [1977]. NIOSH manual of analytical methods. 2nd edition. Cincinnati, OH: U.S. Department of Health, Education, and Welfare, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health. NIOSH [1987a]. NIOSH guide to industrial respiratory protection. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health. DHHS (NIOSH) Publication No. 87-116. NIOSH [1987b]. NIOSH pocket guide to chemical hazards. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health. DHHS (NIOSH) Publication No. 85-114. NIOSH [1987c]. Respirator decision logic. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health. DHHS (NIOSH) Publication No. 87-108. OSHA [1987]. Chemical information manual. Washington, DC: U.S. Department of Labor, Occupational Safety and Health Administration. OSHA [1985]. Computerized information system. Washington, DC: U.S. Department of Labor, Occupational Safety and Health Administration. Parmeggiani L [1983]. Encyclopedia of occupational health and safety. 3rd revised edition. Geneva, Switzerland: International Labour Organisation. Proctor NH, Hughes JP, Fischman ML [1988]. Chemical hazards of the workplace. Philadelphia, PA: J.B. Lippincott Company. RTECS [1989c]. Zirconyl acetate. Bethesda, MD: Registry of Toxic Effects of Chemical Substances, National Library of Medicine.
ACGIH [1986]. Documentation of the threshold limit values and biological exposure indices. 5th edition. Cincinnati, OH: American Conference of Governmental Industrial Hygienists. Hawley's condensed chemical dictionary [1987]. Sax NI, Lewis RJ. 11th edition. New York, NY: Van Nostrand Reinhold Company. Hazardous Substance Fact Sheet [1986]. Zirconium. Trenton, NJ: New Jersey Department of Health. HSDB [1986]. Zirconium. Bethesda, MD: The Hazardous Substances Data Bank, National Library of Medicine. Material Safety Data Sheet No. 17 [1980]. Schenectady, NY: Genium Publishing Corporation. Material Safety Data Sheet No. 212 [1987]. Schenectady, NY: Genium Publishing Corporation. Material Safety Data Sheet No. 213 [1987]. Schenectady, NY: Genium Publishing Corporation. Merck Index [1983]. Windholz M. 10th edition. Rahway, NJ: Merck & Company. NFPA [1986]. Fire protection guide on hazardous materials. 9th edition. Quincy, MA: National Fire Protection Association. NIOSH [January 1981]. NIOSH/OSHA occupational health guidelines. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health. DHHS (NIOSH) Publication No. 81-123. RTECS [1989a]. Zirconium. Bethesda, MD: Registry of Toxic Effects of Chemical Substances, National Library of Medicine. RTECS [1989b]. Zirconium hydride. Bethesda, MD: Registry of Toxic Effects of Chemical Substances, National Library of Medicine. Sax NI, Lewis RJ [1989]. Dangerous properties of industrial materials. 7th edition. New York, NY: Van Nostrand Reinhold Company. Sittig M [1985]. Handbook of toxic and hazardous chemicals. 2nd edition. Park Ridge, NJ: Noyes Publications. USCG [1984a]. CHRIS (chemical hazards response information system) hazardous chemical data manual: Zirconium oxychloride. Washington, DC: U.S. Department of Transportation, U.S. Coast Guard, Commandant Instruction M16465.12A. USCG [1984b]. CHRIS (chemical hazards response information system) hazardous chemical data manual: Zirconium tetrachloride. Washington, DC: U.S. Department of Transportation, U.S. Coast Guard, Commandant Instruction M16465.12A. Weast RC [1984]. CRC handbook of chemistry and physics. 64th edition. Boca Raton, FL: CRC Press, Inc.
|
|||||||||||||||||||||||||||||||||||||||||||
 |
||
|
||