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OSHA 3137 4,4' Methylenedianiline (MDA) for General Industry ![[Cover - 4,4' Methylenedianiline (MDA) in the Construction Industry]](/Publications/OSHA3137/osha3137cvr1.gif)
4,4' Methylenedianiline(MDA) in the Construction Industry U.S. Department of Labor Occupational Safety and Health Administration OSHA 3137 1993 (Reprint) Material contained in this publication is in the public domain and may be reproduced, fully or partially, without permission of the Federal Government. Source credit is requested but not required. The information contained in this publication is not considered a substitute for any provisions of the Occupational Safety and Health Act of 1970 or for any standards issued by OSHA. This information will be made available to sensory impaired individuals upon request. Voice phone: (202) 219-8615; Telecommunications Device for the Deaf (TDD) message referral phone: 1-800-326-2577.  4,4' Methylenedianiline (MDA) in the Construction Industry U.S. Department of Labor Robert B. Reich, Secretary Occupational Safety and Health Administration OSHA 3137 1993 (Reprint) Contents Introduction Scope and Application Provisions of the Standard Permissible Exposure Limit Regulated Areas Decontamination Areas Communication and Training Requirements Emergency Situations Exposure Monitoring Medical Surveillance Methods of Compliance Compliance Program Control Methods Respiratory Protection Protective Clothing and Equipment Hygiene Facilities and Practices Housekeeping Recordkeeping Other Sources of OSHA Assistance Safety and Health Program Management Guidelines State Programs Consultation Services Voluntary Protection Programs (VPP) Training and Education Related Publications States with Approved Plans OSHA Consultation Project Directory OSHA Area Offices Introduction On August 10, 1992, the Occupational Safety and Health Administration (OSHA) issued a final standard regulating occupational exposure to 4,4' Methylenedianiline (MDA), the result of the agency's first negotiated rulemaking effort. MDA is a light-brown crystalline solid with a faint amino-like odor. It is slightly soluble in water and very soluble in alcohol and benzene. MDA is produced commercially by the condensation of aniline and formaldehyde. Crude MDA (40 to 60 percent) is either a liquid or a hard wax-like substance. Purified MDA (99 percent) is either light yellow crystalline flakes or white granules. Routes of exposure to MDA include skin absorption, inhalation, and ingestion. Short-term (acute) overexposure to MDA produces fever, chills, loss of appetite, vomiting, and/or jaundice. Short-term contact with MDA may irritate the skin, eyes, and mucous membranes and sensitization to MDA also may occur. Long-term (chronic) overexposure may cause cancer as well as damage to the liver, kidneys, blood, and spleen. Ninety-eight percent of MDA currently produced is used directly in the manufacture of 4,4' Methylenediphenyl diisocyanate (MDI).1 The remaining 2 percent of MDA is used as a precursor in the manufacture of plastic fibers, antioxidants, dyestuff intermediates, corrosion preventatives, and special polymers. Purified MDA is used in defense applications and in manufacturing epoxy resin curing agents, wire coating applications, polyurethane co-reactants, and pigments and dyes. In the construction industry, MDA is primarily used to coat exterior surfaces, such as concrete structures, pipes, and floors. These surfaces located inside or outside of buildings, usually are coated by spray application. The standard, however, covers both spray and roll-on applications. The following sections discuss the MDA standard as it pertains to the construction industry. OSHA also has developed a separate booklet that discusses the MDA standard's application to the general and maritime industries. Scope and Application The OSHA standard for exposure to MDA in the construction industry is outlined in Title 29 Code of Federal Regulations Part 1926.60. The standard applies to all construction work in which there is exposure to MDA, including:
Provisions of the Standard Permissible Exposure Limit Time-Weighted Average and Short-Term Exposure Limit No employee maybe exposed to MDA above the permissible exposure limit (PEL) of 10 parts per billion (ppb) as an 8-hour time-weighted average (TWA), or above a short-term exposure limit (STEL) of 100 ppb over a 15-minute sampling period. Action Level The action level for a concentration of airborne MDA is 5 ppb as an 8-hour TWA. When the action level is reached, an employer must begin compliance activities such as exposure monitoring, medical surveillance, or temporary removal. Regulated Areas Regulated areas must be established where airborne concentrations exceed the PEL or can reasonably be expected to exceed the PEL and where employees handle or use non-airborne MDA liquids or mixtures. These areas must be demarcated from the rest of the workplace to minimize the number of persons potentially exposed. No eating, drinking, smoking, chewing of tobacco or gum, or appIying of cosmetics is permitted in regulated areas. Access to regulated areas must be limited to authorized persons only, and personal protective equipment and clothing are required to be worn by employees working in these areas. Decontamination Areas Decontamination areas, located outside of but as near as practical to the regulated area, also must be established for decontaminating workers, materials, and equipment contaminated with MDA. The decontamination area must include an equipment storage area, wash area, and clean change area. Communication and Training Requirements An employer performing work with MDA on multi-employer sites must inform other employers at the site of the nature of the work with MDA and the existence of requirements for regulated areas. Warning signs must be posted in each regulated area and at all entrances or accessways to regulated areas. These signs must bear the following information:  Labels for containers of pure MDA must contain the following information:   Emergency Situations The employer must develop a written plan for emergency situations for each construction operation. The employer must identify emergency escape routes at each specific construction site before construction operations begin. The plan also must require the use of appropriate protective equipment and clothing for employees and a means to alert and evacuate employees in the case of an emergency. Exposure Monitoring Breathing-zone air samples that are representative of each employee's exposure to airborne MDA over an 8-hour period will determine employee exposure. Determination of employee exposure to the STEL must be made from breathing zone air samples collected over a 15-minute sampling period. Representative employee exposure will be determined on the basis of one or more samples representing full-shift exposure for each shift for each job class in each work area where MDA exposure can occur. Where the employer can document that exposure levels are equivalent for similar operations in different shifts, the employer only is required to determine representative employee exposure for that operation during one shift. The MDA standard requires that initial monitoring be performed for employees exposed to MDA unless objective or historical monitoring data prove that exposures are below the action level. (See section on Recordkeeping for requirements for monitoring data.) If exposure is at the PEL, monitoring must be repeated every 6 months; if above the PEL, every 3 months; if below the action level, monitoring may be discontinued. The method of monitoring must be accurate to a confidence level of 95 percent and accurate to within plus or minus 25 percent for airborne concentrations of MDA. When there is a change in the production process, chemicals present, control equipment, personnel, or work practices, new monitoring is required. Within 15 working days, the employee must be notified in writing of monitoring results and must be informed of the corrective action the employer is taking to reduce exposures to or below the PEL when the PEL is exceeded. The employer is required to provide the employee or the employee representative(s) an opportunity to observe the measuring or monitoring of employee exposure to MDA. The employer also must perform routine visual inspections of employee skin for dermal exposure (MDA turns skin yellow) and take appropriate corrective action when there is an indication of exposure. The employer must determine the source of exposure, implement protective measures to correct the hazard, and maintain all records of the corrective action. MDA operations within a regulated area need not be monitored periodically if all employees are wearing supplied-air respirators while working in that regulated area. Medical Surveillance A medical surveillance program is required, under the supervision of a licensed physician, without cost, for those employees:
The employer must conduct annual exams following the initial exam, emergency situations, or when the employee develops signs and symptoms associated with MDA exposure. The examining physician must provide in writing the results of these exams to the employer and employee. The employer must provide the examining physician(s) with:
It is important to note that the employer must promptly inform the employee of the right to seek a second opinion following an initial examination. The employer may condition his participation in, and payment for, the multiple physician review mechanism upon the employee taking two actions within 15 days after receipt of the first opinion -- (1) informing the employer of the intention to seek a second opinion; and/or (2) initiating steps to make an appointment with a second physician. If the second set of determinations differ from the initial ones, the employer must ensure the disagreement is resolved between the two physicians. If unable to resolve such a disagreement quickly, the affected employee and employer through their physicians may designate a third physician to review findings and conduct exams, tests, and discussions with the prior physicians. Medical Removal Provisions An employer must temporarily remove an employee from work when occupational exposure to MDA is at or above the action level or where dermal exposure to MDA may occur in the following circumstances:
An employee may return to former job status when:
The employer must provide an employee up to 6 months of medical removal protection benefits4 each time the employee is removed from MDA exposure. The employer, however, may condition medical removal protection benefits on the employee's participation in followup medical surveillance provided. If the removed employee files a worker's compensation claim, the employer must continue to provide medical removal protection benefits pending disposition of the claim. When an employer voluntarily removes or places limitations on an employee who is exposed to MDA, medical removal protection benefits are still required. If an employee does not recover within 6 months of removal from MDA exposure, the employer must:
Methods of Compliance Compliance Program The employer must establish and implement a written compliance program to reduce employee exposure to the PEL or below by the use of engineering and work practice controls and by the use of respiratory protection. Such plans must be reviewed every 12 months to ensure they reflect the current status of operations. Control Methods Engineering and work practice controls are primary methods used to reduce occupational exposure to MDA to levels at or below the PEL. To achieve compliance with the PEL, one or a combination of the following control methods must be used:
Employee rotation, however, is prohibited as a means to reduce exposure. Compressed air may not be used to remove MDA unless it is used in conjunction with an enclosed ventilation system designed to capture the dust cloud created by the compressed air. Respiratory Protection Employers must provide, at no cost to the employee, and ensure the use of respirators when engineering and work practice controls are being installed; when engineering and work practice controls are not sufficient to reduce exposure to or below the PEL; when engineering controls are not feasible in repair or maintenance and spray application processes; and during emergencies. Respirators must be selected from among those approved by the Mine Safety and Health Administration and the National Institute for Occupational Safety and Health (NIOSH). (See chart page 16.) Where respiratory protection is required, the employer must develop a respiratory protection program.  Where air-purifying respirators are used, the employer must replace the air-purifying element as needed to maintain effectiveness. Employees who wear respirators are allowed to leave the regulated area to adjust or readjust the facepiece or to wash their faces or respirator facepieces to minimize skin irritation associated with respirator use. Quantitative or qualitative fit testing must be performed and recorded at the initial fitting and at least annually thereafter for each employee wearing a negative-pressure respirator. Protective Clothing and Equipment The employer must provide personal protective equipment and clothing, at no cost to the employee, and ensure their proper use when the employee is subject to dermal exposure to MDA; where liquids containing MDA can be splashed into the eyes; or where airborne concentrations of MDA are in excess of the PEL. Recommended protective clothing and equipment may include, but are not limited to aprons, coveralls, gloves, foot coverings, faceshields, and/or goggles. Employees must use decontamination areas to remove MDA-contaminated work clothing and equipment at the end of the workshift. Employers also must ensure that during their workshift, employees remove all MDA-contaminated protective clothing or equipment prior to leaving a regulated area. All protective clothing and equipment must be cleaned, laundered, repaired, or replaced as needed to maintain effectiveness. When rips or tears are detected, the personal protective equipment and clothing must be repaired or replaced immediately. No MDA-contaminated protective work gear may be removed from a decontamination area except by authorized employees for laundry, maintenance, or disposal. MDA-contaminated items must be placed, stored, and transported in sealed, labeled, and closed containers or impermeable bags. Removal of MDA via blowing, shaking, or any method that allows MDA reentry into the workplace is prohibited. The employer must inform those responsible for laundering or cleaning protective clothing and equipment of the potential harmful effects of MDA exposure. Hygiene Facilities and Practices The employer must provide decontamination areas for those employees required to work in regulated areas. In small-scale short-term operations, however, the employer may permit employees to clean their protective clothing or dispose of it before leaving the regulated area. Change areas must be equipped with separate storage facilities for personal protective equipment and clothing and street clothing. The equipment area must be supplied with impermeable labeled bags and containers for the disposal of contaminated protective equipment and clothing. If these bags or containers and their contents are to be removed from the workplace to be cleaned, disposed of, or maintained, they must be labeled and sealed to prevent MDA contact. When feasible, shower facilities must be provided where the possibility exists of employee exposure to airborne MDA in excess of the PEL. Where dermal exposure to MDA occurs, the employer must ensure that materials spilled or deposited on the skin are removed as soon as possible. Whenever food or beverages are consumed at the work site and employees are exposed to MDA, the employer must provide clean lunch areas where MDA levels are below the action level or where no dermal exposure to MDA can occur. Prior to eating, drinking, smoking, or applying cosmetics, employees must wash their hands and faces with soap and water. No one may enter lunch facilities with contaminated protective work clothing or equipment. Housekeeping All surfaces must be maintained as free as possible of accumulations of MDA. A regular visual inspection program must be instituted to detect MDA leaks, spills, or discharges. All leaks must be repaired, and liquid or dust spills promptly cleaned. The use of compressed air for cleaning is prohibited, but shoveling or dry sweeping is permissible where HEPA-filtered vacuuming or wet cleaning is not feasible. In any case, contaminated debris -- including waste, scrap, debris, bags, containers, equipment and clothing contaminated with MDA -- must be collected and disposed of in a manner that prevents re-entry of MDA into the workplace. Recordkeeping All records must be made available to affected employees or their representative(s), OSHA, and NIOSH upon request in accordance with the Access to Employee Exposure and Medical Records standard, Title 29 CFR Part 1910.20. If the employer ceases to do business, all records must be transferred to successor employers or, if there is no successor, to NIOSH. In addition, the MDA standard has specific requirements for keeping records pertaining to objective and historical monitoring data and training. Objective Data Under the MDA standard, an accurate record must be maintained of initial monitoring or of the objective data that exempted the operations from initial monitoring requirements. The record must be kept for the duration of reliance on the data and must include at least the following information:
The MDA standard also requires that an accurate record be kept of all historical data upon which the employer has relied to demonstrate that a particular job will be below the action level to exempt initial monitoring requirements. The information must reflect the following conditions:
Exposure Measurements and Medical Surveillance The employer must keep an accurate record of all measurements taken to monitor employee MDA exposure for at least 30 years. This record must include:
The MDA standard requires employers to maintain all employee training records for 1 year beyond the last date of the employee's employment. Other Sources of OSHA Assistance Safety and Health Program Management Guidelines Effective management of worker safety and health protection is a decisive factor in reducing the extent and severity of work-related injuries and illnesses and their related costs. To assist employers and employees in developing effective safety and health programs, OSHA published recommended Safety and Health Program Management Guidelines (January 26, 1989, 54 FR:3908-3916). These voluntary guidelines apply to all places of employment covered by OSHA. The guidelines identify four general elements that are critical to the development of a successful safety and health management program:
State Programs The Occupational Safety and Health (OSH) Act of 1970 encourages states to develop and operate their own job safety and health plans. OSHA approves and monitors these plans. There are currently 25 state plan states: 23 of these states administer plans covering both private and public (state and local government) employment; the other 2 states, Connecticut and New York, cover the public sector only. The 25 states and territories with their own OSHA-approved occupational safety and health plans must adopt standards identical to, or at least as effective as, the federal standards. Until a state standard is promulgated, OSHA will provide interim enforcement assistance, as appropriate, in these states. A listing of states with approved plans appears at the end of this booklet. Consultation Services Consultation assistance is available on request to employers who want help in establishing and maintaining a safe and healthful workplace. Largely funded by OSHA, the service is provided at no cost to the employer. Primarily developed for smaller employers with more hazardous operations, the consultation service is delivered by state government agencies or universities employing professional safety consultants and health consultants. Comprehensive assistance includes an appraisal of all mechanical, physical work practices, and environmental hazards of the workplace and all aspects of the employer's present job safety and health program. No penalties are proposed or citations issued for hazards identified by the consultant. For more information concerning consultation assistance, see the list of consultation projects listed at the end of this publication. Voluntary Protection Programs (VPP) Voluntary protection programs and onsite consultation services, when coupled with an effective enforcement program, expand worker protection to help meet the goals of the OSH Act. The three VPPs -- Star, Merit, and Demonstration -- are designed to recognize outstanding achievement by companies that have successfully incorporated safety and health programs into their total management system. They motivate others to achieve excellent safety and health results in the same outstanding way as they establish a cooperative relationship between employers, employees, and OSHA. For additional information on VPPs and how to apply, contact the OSHA national, regional, or area offices listed at the end of this publication. Training and Education OSHA's area offices offer a variety of informational services, such as publications, audiovisual aids, technical advice, and speakers for special engagements. OSHA's Training Institute in Des Plaines, IL, provides basic and advanced courses in safety and health for federal and state compliance officers, state consultants, federal agency personnel, and private sector employers, employees, and their representatives. OSHA also provides funds to nonprofit organizations, through grants, to conduct workplace training and education in subjects where OSHA believes there is a lack of workplace training. Grants are awarded annually, with a 1-year renewal possible. Grant recipients are expected to contribute 20 percent of the total grant cost. For more information on grants, training, and education, contact the OSHA Training Institute, Office of Training and Education, 1555 Times Drive, Des Plaines, IL 60018, (708) 297-4810. For further information on any OSHA program, contact your nearest OSHA regional or area office listed at the end of this publication. Related Publications Single free copies of the following publications can be obtained from the OSHA Publications Office, 200 Constitution Avenue, NW, Room N-3101, Washington, DC 20210. Send a self-addressed mailing label with your request. All About OSHA - OSHA 2056 Chemical Hazard Communication - OSHA 3084 Consultation Services for the Employer - OSHA 3047 4,4' Methylenedianiline (MDA) for General Industry - OSHA 3135 How to Prepare for Workplace Emergencies - OSHA 3088 OSHA Employee Workplace Rights - OSHA 3021 OSHA Inspections - OSHA 2098 Personal Protective Equipment - OSHA 3151 Respiratory Protection - OSHA 3079 The following publications are available from the Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402, (202) 783-3238. Include GPO Order No. and make checks payable to Superintendent of Documents. Hazard Communication -- A Compliance Kit (OSHA 3104) (A reference guide to step-by-step requirements for compliance with the OSHA standard.) Order No. 929-022-00000-9; cost $18.00 domestic; $22.50 foreign. Hazard Communication Guidelines for Compliance (OSHA 3111) Order No. 029-016-00127-1; cost $1.00. Principal Emergency Response and Preparedness Requirements in OSHA Standards and Guidance for Safety and Health Programs (OSHA 3122) Order No. 029-016-00136-1; cost $2.50. States with Approved Plans COMMISSIONER Alaska Department of Labor 1111 West 8th Street Room 306 Juneau, AK 99801 (907) 465-2700 DIRECTOR Industrial Commission of Arizona 800 W. Washington Phoenix, AZ 85007 (602) 542-5795 DIRECTOR California Department of Industrial Relations 455 Golden Gate Avenue 4th Floor San Francisco, CA 94102 (415) 703-4590 COMMISSIONER Connecticut Department of Labor 200 Folly Brook Boulevard Wethersfield, CT 06109 (203) 566-5123 DIRECTOR Hawaii Department of Labor and Industrial Relations 830 Punchbowl Street Honolulu, HI 96813 (808) 586-8844 COMMISSIONER Indiana Department of Labor State Office Building 402 West Washington St. Room W195 Indianapolis, IN 46204-2287 (317) 232-2378 COMMISSIONER Iowa Division of Labor Services 1000 E. Grand Avenue Des Moines, IA 50319 (515) 281-3447 SECRETARY Kentucky Labor Cabinet 1049 U.S. Highway, 127 South Frankfort, KY 40601 (502) 564-3070 COMMISSIONER Maryland Division of Labor and Industry Department of Licensing and Regulation 501 St. Paul Place, 2nd Floor Baltimore, MD 21202-2272 (301) 333-4179 DIRECTOR Michigan Department of Labor Victor Office Center 201 N. Washington Square P.O. Box 30015 Lansing, MI 48933 (517) 373-9600 DIRECTOR Michigan Department of Public Health 3423 North Logan Street Box 30195 Lansing, MI 48909 (517) 335-8022 COMMISSIONER Minnesota Department of Labor and Industry 443 Lafayette Road St. Paul, MN 55155 (612) 296-2342 DIRECTOR Nevada Department of Industrial Relations Division of Occupational Safety and Health Capitol Complex 1370 S. Curry Street Carson City, NV 89710 (702) 687-3032 SECRETARY New Mexico Environment Department Occupational Health and Safety Bureau 1190 St. Francis Drive P.O. Box 26110 Santa Fe, NM 87502 (505) 827-2850 COMMISSIONER New York Department of Labor State Office Building Campus 12 - Room 457 Albany, NY 12240 (518) 457-2741 COMMISSIONER North Carolina Department of Labor 4 West Edenton Street Raleigh, NC 27601 (919) 733-0360 ADMINISTRATOR Oregon Occupational Safety and Health Division Oregon Dept. of Insurance and Finance, Rm 160 21 Labor and Industries Bldg. Summer & Chemeketa NE Salem, OR 97310 (503) 378-3272 SECRETARY Puerto Rico Department of Labor and Human Resources Prudencio Rivera Martinez Building 505 Munoz Rivera Avenue Hato Rey, PR 00918 (809) 754-2119 COMMISSIONER South Carolina Department of Labor 3600 Forest Drive P.O. Box 11329 Columbia, SC 29211-1329 (803) 734-9594 COMMISSIONER Tennessee Department of Labor 501 Union Building Suite "A" - 2nd Floor Nashville, TN 37243-0655 (615) 741-2582 ADMINISTRATOR Utah Occupational Safety and Health 160 East 300 South 3rd Floor P.O. Box 146600 Salt Lake City, UT 84110-6600 (801) 530-6880 COMMISSIONER Vermont Department of Labor and Industry 120 State Street Montpelier, VT 05620 (802) 828-2288 COMMISSIONER Virgin Islands Department of Labor 2131 Hospital Street Christiansted St. Croix, VI 00840-4666 (809) 773-1994 COMMISSIONER Virginia Department of Labor and Industry Powers-Taylor Building 13 South 13th Street Richmond, VA 23219 (804) 786-2376 DIRECTOR Washington Department of Labor and Industries General Administration Building P.O. Box 44001 Olympia, WA 98504-4001 (206) 753-6307 DIRECTOR Department of Employment Division of Employment Affairs Occupational Safety and Health Administration Herschler Building, 2nd Floor East 122 West 25th Street Cheyenne, WY 82002 (307) 777-7672 OSHA Consultation Project Directory
S - Safety OSHA Area Offices
U.S. Department of Labor Occupational Safety and Health Administration Regional Offices Region I (CT,* MA, ME, NH, RI, VT*) 133 Portland Street 1st Floor Boston, MA 02114 Telephone: (617) 565-7164 Region II (NJ, NY,* PR,* VI*) 201 Varick Street Room 670 New York, NY 10014 Telephone: (212) 337-2378 Region III (DC, DE, MD,* PA, VA,* WV) Gateway Building, Suite 2100 3535 Market Street Philadelphia, PA 19104 Telephone: (215) 596-1201 Region IV (AL, FL, GA, KY,* MS, NC,* SC,* TN*) 1375 Peachtree Street, N.E. Suite 587 Atlanta, GA 30367 Telephone: (404) 347-3573 Region V (IL, IN,* MI,* MN,* OH, WI) 230 South Dearborn Street Room 3244 Chicago, IL 60604 Telephone: (312) 353-2220 Region VI (AR, LA, NM,* OK, TX) 525 Griffin Street Room 602 Dallas, TX 75202 Telephone: (214) 767-4731 Region VII (IA,* KS, MO, NE) 911 Walnut Street, Room 406 Kansas City, MO 64106 Telephone: (816) 426-5861 Region VIII (CO, MT, ND, SD, UT,* WY*) Federal Building, Room 1576 1961 Stout Street Denver, CO 80294 Telephone: (303) 844-3061 Region IX (American Samoa, AZ,* CA,* Guam, HI,* NV,* Trust Territories of the Pacific) 71 Stevenson Street Room 415 San Francisco, CA 94105 Telephone: (415) 744-6670 Region X (AK,* ID, OR,* WA*) 1111 Third Avenue Suite 715 Seattle, WA 98101-3212 Telephone: (206) 553-5930 Footnote(1) Federal Register 57(154):35633, August 10, 1992. (Back to Text) Footnote(2) Under the provisions of the Hazard Communication standard, Title 29 CFR Part 1910.1200, employers must inform employees of the hazards and the identities of workplace chemicals to which they are exposed when working. (Back to Text) Footnote(3) A final medical determination is the outcome of the physician's review mechanism required through the medical surveillance provisions of the standard. (Back to Text) Footnote(4) Medical removal protection benefits include maintaining the employee's earnings, seniority, and other employment rights and benefits as they would be if no removal had occurred. (Back to Text) Footnote(5) A high-efficiency particulate air (HEPA) filter is at least 99.97 , percent efficient against mono-dispersed particles of 0.3 micrometers or larger. (Back to Text) Footnote(*) These states and territories operate their own OSHA-approved job safety and health programs (Connecticut and New York plans cover public employees only). States with approved programs must have a standard that is identical to, or at least as effective as, the federal standard. (Back to Text) |
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