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Title 8. Industrial Relations
Division 1. Department of Industrial Relations
Chapter 4. Division of Industrial Safety
Subchapter 7. General Industry Safety Orders
Group 16. Control of Hazardous Substances
Article 110. Regulated Carcinogens

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§5215. 4,4'-Methylenebis(2-Chloroaniline).

(a) Scope and Application.
(1) This section establishes requirements for the control of employee exposure to 4,4′-methylenebis(2-chloroaniline), MBOCA, Chemical Abstracts Service Registry No. 101144.
(2) This section applies to the manufacture, packaging, repackaging, storage, handling and use of MBOCA, but does not apply to:
(A) Fabricated products; or
(B) The storage or transportation of MBOCA in sealed, unbroken containers except for labeling of containers under Section 5215(j)(3), reporting of use under Section 5215(m) and preparation of emergency plan under Section 5215(h)(4).
(3) The requirements of this section are subject to the provisions of the Occupational Carcinogens Control Act of 1976 (Health and Safety Code, Division 20, Chapter 2).
(b) Definitions.
Authorized Person. Any person specifically authorized by the employer to handle or use MBOCA or to enter a controlled access area or any person entering such an area as a designated representative of employees for the purpose of exercising an opportunity to observe monitoring and measuring procedures.
Chief. The Chief of the Division of Occupational Safety and Health, P.O. Box 420603, San Francisco, CA 94142.
Controlled Access Area. An area where entry and exit are restricted and controlled for the purpose of limiting occupational exposure to MBOCA.
Engineering Controls. Methods of controlling occupational exposure to injurious materials or conditions by means of general or local exhaust ventilation, by process modification, or by isolation or enclosure of health hazard-producing operation or machinery. Engineering controls do not include employee personal protection.
Work Practice Controls. Methods of controlling occupational exposure to injurious materials or conditions by means of written procedures specifying handling, employee personal protection and personal hygiene.
Fabricated Products. Any elastomer or foam product processed so that the unreacted MBOCA is less than 1.0 percent by weight of polymer.
MBOCA. 4,4′-Methylenebis(2-chloroaniline), Chemical Abstracts Service Registry No. 101144. Appendix A contains other synonyms.
(c) Permissible Exposure Limit.
(1) Exposure to MBOCA shall be controlled such that no employee's urine contains more than 100 micrograms (μg) of MBOCA per liter of urine when the specific gravity of the urine is adjusted to 1.024.
(2) Where specific urine samples are not received as requested by the Chief or his authorized representatives:
(A) Employees shall not be exposed to an 8-hour time-weighted average concentration of MBOCA in excess of 10μg (micrograms) per cubic meter of air, and
(B) Employees shall not be exposed to a ceiling concentration in excess of 50μg per cubic meter of air during any 15-minute period, and
(C) Accessible surfaces which employees are likely to contact in controlled access areas or uncontrolled areas during their normal work shall not exceed 100μg MBOCA per 100 cm2 of surface. For regulatory purposes, the average of at least five wipe samples shall be used; if one sample exceeds the mean by a factor of 10 or more, it will be rejected as not being representative.
(d) Monitoring.
(1) Within 30 days of the effective date of this standard, employers using more than one kilogram of MBOCA regardless of concentration, dilution or form, except frozen premix, in any 6-month period shall institute a program of monitoring of surface contamination and urine analysis.
(2) All authorized employees who enter a controlled access area shall have the urine analysis repeated quarterly. Samples are to be obtained near the end of the work shift.
(3)(A) Employees whose urinary levels of MBOCA exceed 100 μg/1 with specific gravity adjusted to 1.024 shall be tested at least monthly until 2 consecutive samples taken no less than 3 days apart have been reduced to below 100 μg/liter.
(B) No later than 6 months from the effective date of this standard, employees whose urinary levels of MBOCA exceed 100 μg/1 with specific gravity adjusted to 1.024 shall be tested at least monthly until 2 consecutive samples taken no less than 3 days apart have been reduced to below 30μg/liter.
(4) The method of monitoring and measurement shall be accurate and precise so that 95% of the determinations are within 25% of the true value at the exposure limit.
(5) Employees or their designated representatives shall be afforded reasonable opportunity to observe the monitoring and measuring required by this paragraph.
(6) Within 10 working days following any monitoring and measuring which discloses that any employee has been exposed in excess of the permissible exposure limit, each such employee shall be notified in writing of the numerical results of the monitoring.
(e) Controlled Access Area.
(1) All areas outside of controlled access areas shall be maintained so that MBOCA contamination of surfaces does not exceed 100 μg per 100 cm2.
(2) All equipment and materials removed from a controlled access area shall be decontaminated so that MBOCA does not exceed 100 μg per 100 cm2 of surface.
(3) Entry to controlled access areas shall be limited to authorized personnel and escorted visitors. A daily roster shall be made of persons who enter the controlled access area.
(4) Storage, consumption or use of food, beverages, cosmetics, smoking or chewing materials are prohibited in controlled access areas, except for foot-operated drinking fountains.
(f) Methods of Control.
(1) Employee exposures which exceed the limits specified in Section 5215(c) shall be prevented by engineering controls whenever feasible.
(2) Written plans, including timetables for attaining compliance with this section, shall be developed and furnished on request for examination and copying by the Chief or his authorized representative. Such plans shall be updated at least every six months until compliance is achieved and maintained to reflect current methods of control.
(g) Respiratory Protection.
(1) Respiratory protective equipment shall be provided in accordance with this subsection and Section 5144. Records of face fit tests shall be maintained.
(2) Appropriate selection, provision, and use of respiratory protective equipment shall be based on the following table.
Concentration of Airborne
Respiratory Type
1. Not greater than 0.1 milligram
Air-purifying with high efficiency parti-
per cubic meter.
culate filter* and half-mask;
Any supplied air respirator
with half-mask.
2. Not greater than 0.5 milligrams
Air-purifying, with high efficiency
per cubic meter.
particulate filter* and full facepiece;
Any supplied air respirator
with full facepiece;
Any self-contained breathing
apparatus with full facepiece.
Concentration of Airborne
Respiratory Type
3. Not greater 10 milligrams
Powered air-purifying, with high effici-
per cubic meter
ency particulate filter*, half-mask, full
facepiece, hood or helmet;
Supplied air, operated in
positive pressure mode, with
4. Not greater than 20 milligrams
Supplied air, operated in positive pressure
per cubic meter
mode, with full facepiece, hood, helmet,
or suit.
5. Firefighting and/or any high
Self-contained breathing apparatus with
or potentially high concentration
full facepiece operated in pressure demand
Combination breathing appar-
atus: supplied-air, positive
pressure, full facepiece
respirator with auxiliary
self-contained compressed air
supply with sufficient service
time for escape.
* High efficiency filter-99.97 percent efficiency against 0.3 micrometer monodisperse diethylhexyl phthalate (DOP) particles.
(3) Employee Options.
(A) Employees who wear respirators shall be allowed reasonable time to leave work areas to wash the face and respirator facepiece to prevent potential skin irritation associated with respirator use.
(B) Where air-purifying respirators are required for protection against MBOCA, the employee shall be permitted to change filter elements whenever an increase in breathing resistance is detected, a the employer shall maintain an adequate supply of filter elements for this purpose.
(C) Where compliance with this section requires employee use of an air-purifying respirator for a major portion of the work shift, the employer shall provide, at the option of each affected employee, a powered respirator within 120 days of the effective date of this order.
(h) Hazardous Operations and Emergencies.
(1) Employees engaged in hazardous operations, shall be provided with and required to use:
(A) Respiratory protection that is in accordance with Section 5215(g).
(B) Protective garments to prevent skin contact. The protective garments shall be selected for the operation and its possible exposure conditions.
(C) Eye and face protection where splash hazards from liquid or solution of MBOCA exist.
(2) Employees shall be decontaminated before removing protective garments.
(3) Protective garments shall be provided clean and dry for each use of the garments.
(4) A written operational plan for hazardous operations and emergency situations shall be developed for each facility manufacturing, processing, handling, packaging, repackaging, releasing, storing, selling, transferring, transporting, disposing, or using MBOCA. Appropriate portions of the plan shall be implemented in the event of an emergency. The plan shall specifically provide that:
(A) Employees engaged in hazardous operations or correcting situations of existing hazardous spills shall be equipped as required in this paragraph.
(B) Other employees not so equipped shall evacuate the area and not return until conditions are controlled by methods required in Section 5215(f) and the emergency is abated.
(C) Areas containing hazardous operations, or where the emergency currently exists, shall be posted in accordance with Section 5215(l)(2).
(D) Reports shall be made as required by Section 5215(m).
(E) An employee with a known contact with MBOCA shall be required to shower and wash hair as soon as possible, unless prevented by physical injuries, and shall be given the option to provide a urine specimen for analysis of MBOCA content.
(i) Decontamination and Disposal. All waste contaminated with MBOCA shall be disposed of in accordance with Hazardous Waste Disposal Regulations, Title 22, California Code of Regulations, Sections 60001 through 60283.
(1) All shipping containers shall be considered contaminated until decontaminated, or shown not to be contaminated.
(2) Contaminated surfaces may be decontaminated by:
(A) Removal of MBOCA by appropriate mechanical and chemical means; or
(B) Reacting and sealing the MBOCA with urethane or isocyanate solutions.
(3) Decontaminated surfaces shall be retested by wipe samples or fixed with a label showing date and method by which surface was decontaminated, and the label required by Section 5215(j)(3).
(j) Communication of MBOCA hazards to employees.
(1) Hazard communication - general.
(A) Chemical manufacturers, importers, distributors and employers shall comply with all requirements of the Hazard Communication Standard (HCS) (Section 5194) for MBOCA.
(B) In classifying the hazards of MBOCA at least the following hazards are to be addressed: cancer; liver effects; blood effects; kidney effects; and acute toxicity effects.
(C) Employers shall include MBOCA in the hazard communication program established to comply with the HCS (Section 5194). Employers shall ensure that each employee has access to labels on containers of MBOCA and to safety data sheets, and is trained in accordance with the requirements of HCS and subsection (j)(4) of this section.
(2) Signs.
(A) The employer shall post entrances to controlled access areas with legible signs bearing the legend:
(B) The employer shall post signs at areas containing hazardous operations or where emergencies currently exist. The signs shall be legible and bear the legend:
(C) Prior to June 1, 2016, employers may use the following legend in lieu of that specified in subsection (j)(2)(A) of this section:
(D) Prior to June 1, 2016, employers may use the following legend in lieu of that specified in subsection (j)(2)(B) of this section:
(E) Prescribed emergency procedures shall be posted or available in appropriate locations.
(3) Labels.
(A) The employer shall ensure that labels or other appropriate forms of warning are provided for containers of MBOCA within the workplace. The labels shall comply with the requirements of subsection (j)(1) of this section and section 5194(f).
(B) Prior to June 1, 2015, employers may include the following information for containers of MBOCA in lieu of the labeling requirements in subsection (j)(1) of this section:
(C) No statement shall appear on or near any required sign, label, or instruction which contradicts or detracts from the effect of any required warning, information, or instruction.
(4) Information and Training.
Each employee engaged in an operation or activity where MBOCA is used shall receive an Information and Training Program including the information or requirements of this subsection and precautions for its safe use.
(A) Instruction shall include all information in the Safety Data Sheets applicable to the specific MBOCA-containing product to which there is possible exposure. Such a program shall be provided without cost to the employee.
(B) The program shall include:
1. The nature of the carcinogenic hazard, including local and systemic toxicity.
2. The specific nature of the operation involving MBOCA which could result in exposure in excess of the permissible exposure limits and necessary protective steps.
3. The purpose, proper use, and limitations of respiratory protective devices, gloves and protective garments.
4. The purpose for, and application of, decontamination procedures.
5. The purpose for, and significance of, emergency practices and procedures.
6. The employee's specific role in prescribed emergency procedures.
7. Employee familiarization with the prescribed emergency procedures and rehearsal in their application.
8. Specific information to aid the employee in recognition of conditions which may result in exposure to MBOCA.
9. The purpose for, and application of, specific first aid procedures and practices.
10. The purpose for, and description of, the monitoring program.
11. The purpose for, and description of, the medical surveillance program.
12. Employee rights under this section and the CAL/OSHA program.
13. A review of this section at the employee's first training and indoctrination program and annually thereafter.
(C) All materials relating to the program shall be provided on request to the Chief or his authorized representative.
(D) The employer shall make a copy of this section and its appendices readily available to all affected employees.
(k) Medical Surveillance. A program of medical surveillance shall be instituted for each authorized person. The employer shall provide each such employee with an opportunity for medical examinations and tests in accordance with this subsection. All medical examinations and procedures shall be performed by or under the supervision of a licensed physician, and shall be provided without cost to the employee.
(1) Frequency of medical examinations:
(A) Prior to time of initial assignment or within 90 days of the effective date of this order.
(B) At least every 3 years for the first 10 years of employment involving the use of MBOCA, and annually thereafter.
(2) Content of medical examinations:
(A) A comprehensive medical history with emphasis on pertinent medical, occupational, genetic, and environmental factors (employee and employee's family).
(B) A comprehensive physical examination with emphasis on detecting abnormalities of the liver, pulmonary system, urinary system, breasts, and hematologic system.
(C) Evaluation of the advisability of the employee using negative or positive pressure respirators.
(D) Laboratory tests shall include:
1. Chest X-ray (14-inch by 17-inch, posterior-anterior).
2. Serum total bilirubin.
3. Serum alkaline phosphatase.
4. Serum glutamic oxaloacetic transaminase (SGOT) or serum glutamic pyruvic transaminase (SGPT).
5. Complete blood count (CBC).
6. Complete urinalysis (UA).
(3) Information provided to the physician by the employer:
(A) A copy of this standard and its appendices.
(B) The results of the biological monitoring required by this section since the last medical examination.
(4) The examining physician's written opinion to the employer regarding each employee shall include:
(A) The results of the medical tests performed.
(B) Any medical condition that could place the employee at an increased risk of material impairment of health from his employment.
(5) The employer shall provide a copy of the written opinion to the affected employee.
(l) Records.
(1) All records maintained in accordance with this section shall include the name an social security number of each employee where relevant.
(2) Records of required monitoring and measuring, face fit tests, medical records, and authorized personnel rosters shall be made and shall be available upon request for examination and copying to authorized representatives of the Chief. Such records shall also be provided upon request to authorized representatives of the Chief in accordance with Section 3204.
(3) The daily roster of employees entering regulated areas or a summary of the rosters shall be retained for a period of a year. The roster and/or summaries shall be provided upon request to authorized representatives of the Chief.
(4) Monitoring and measuring records shall be maintained for not less than 30 years and shall contain the following information:
(A) Date, location, and concentration of each determination;
(B) Instruments and methods used;
(C) Any additional information necessary to determine individual employee exposure.
(5) Face fit tests shall be maintained for not less than one year and shall include persons tested, method used and results.
(6) The employer shall maintain the originals or true copies of the physician's written opinions regarding each affected employee for the duration of the employment plus 20 years or for 30 years, whichever is longer.
(7) In the event that the employer ceases to do business and there is no successor to receive and retain the records for the prescribed period, these records shall be transmitted by Registered Mail to the Director of National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services.
The employer shall also comply with any additional requirements involving the transfer of records set forth in Section 3204.
(8) Employees, former employees, or their designated representatives shall be provided records of required monitoring and measuring in accordance with Section 3204.
(9) Upon written request of any employee or former employee, a copy of the medical record of that employee shall be furnished to the employee or to any physician or other individual or organization designated by the employee or former employee in accordance with Section 3204.
(m) Reports. See section 5203.
Appendix A
Physical and Chemical Data
(1) Synonyms:
4,4′-methylenebis(2-chloroaniline) - methylenebis(2-chloroaniline)
di(4-amino-3-clorofenil)metano (Italian)
3,3′ dicloro-4,4′ diaminodifenilmetano (Italian)
4,4′-metilene-bis-o-cloranilina (Italian)
3,3′-dichlor-4,4′-diaminodiphenylmethan (German)
MOCA (R), DuPont
Cyanaset (R), American Cyanamid
Curalon M (R), Uniroyal
Curene 442 (R), Anderson Chemical
Bis-Amine A (R), Wakayama Seiko/Polyester Corp.
Activator M (R), MVR
Cuamine M, Ihara Chemical
MBK, Kulkman
(2) Identification and General Properties:
Structural formula:
Molecular weight: 267
Specific gravity of solid: 1.44 at 75o (24oC)
Melting range: 212-228oF (100-109oC)
Color: light creamy yellow to light gray tan
Odor: slight
Appendix B
Supplemental Medical Information
(1) When required tests under Section 5215(k)(2) reveal abnormalities, the tests should be repeated as soon as practicable within 30 days. If the tests remain abnormal, consideration should be given to withdrawing the employee from contact with 4,4′-methylenebis(2-chloroaniline) while a more comprehensive examination is made.
(2) Additional tests that may be useful;
(A) Pulmonary system
1. Sputum cytology
2. Bronchoscopy with bronchial washings for cytology and tissue biopsy.
3. Computerized axial tomography with or without use of a contrast medium.
(B) Liver
1. Liver scan
2. Percutaneous liver biopsy
3. Hepatic angiography
(C) Urinary system
1. Urine cytology, 24-hour specimen
2. Blood urea nitrogen (BUN)
3. Serum creatinine
4. Creatinine clearance
5. Radioactive renogram
6. Intravenous pyelogram (IVP)
7. Cystoscopy with retrograde pyelogram and/or urinary bladder biopsy, as indicated.
8. Percutaneous renal biopsy.
(D) Breasts
1. Mammography
2. Breasts biopsy
(3) Known toxicity of 4,4′-methylenebis(2-chloroaniline)
(A) Pulmonary carcinoma*
(B) Malignant tumors of the liver*
(C) Carcinoma of the breast*
(D) Carcinoma of the urinary bladder*
(E) Kidney irritation
(F) Methemoglobinemia*
*Observed in experimental animals only
(4) Routes of absorption
(A) Skin (primary)
(B) Inhalation (secondary)
(C) Ingestion (minor)
Appendix C
Analytical Methods
(Laboratory methods used by CAL/OSHA will be furnished on request.)
Note: Authority cited: Sections 142.3, 9020, 9030 and 9040, Labor Code. Reference: Sections 142.3, 9004(d), 9009, 9020, 9030, 9031 and 9040, Labor Code.
1. New section and Appendices A-C filed 5-25-79; effective thirtieth day thereafter (Register 79, No. 21).
2. Amendment of subsection (m) filed 3-20-81; effective thirtieth day thereafter (Register 81, No. 12).
3. Editorial correction of subsection (b) filed 3-3-83 (Register 83, No. 10).
4. Change without regulatory effect amending definition of Chief in subsection (b) filed 3-4-92 pursuant to section 100, title 1, California Code of Regulations (Register 92, No. 19).
5. Amendment of subsection (n), repealer of subsections (n)(1)-(3) and amendment of Note filed 7-6-99; operative 8-5-99 (Register 99, No. 28).
6. Change without regulatory effect providing more legible illustration within Appendix A filed 3-2-2009 pursuant to section 100, title 1, California Code of Regulations (Register 2009, No. 10).
7. Amendment filed 5-5-2014; operative 5-6-2014 pursuant to Government Code section 11343.4(b)(3) (Register 2014, No. 19).
8. Editorial correction removing duplicate subsection (j) (Register 2014, No. 31).
9. Editorial correction of subsections (d)(3)(A) and (d)(3)(B) (Register 2016, No. 35).

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