This occupational health standard establishes requirements for employers to control occupational exposure to methylene chloride (MC). Employees exposed to MC are at increased risk of developing cancer, adverse effects on the heart, central nervous system and liver, and skin or eye irritation. Exposure may occur through inhalation, by absorption through the skin, or through contact with the skin. MC is a solvent which is used in many different types of work activities, such as paint stripping, polyurethane foam manufacturing, and cleaning and degreasing. Under the requirements of subsection (d), each covered employer must make an initial determination of each employee's exposure to MC. If the employer determines that employees are exposed below the action level, the only other provisions of this section that apply are that a record must be made of the determination, the employees must receive information and training under subsection (l) and, where appropriate, employees must be protected from contact with liquid MC under subsection (h). The provisions of the MC standard are as follows:
Action level means a concentration of airborne MC of 12.5 parts per million (ppm) calculated as an eight (8)-hour time-weighted average (TWA).
Authorized person means any person specifically authorized by the employer and required by work duties to be present in regulated areas, or any person entering such an area as a designated representative of employees for the purpose of exercising the right to observe monitoring and measuring procedures under subsection (d), or any other person authorized by the Chief.
Chief means the Chief of the Division of Occupational Safety and Health, or designee.
Emergency means any occurrence, such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment, which results, or is likely to result in an uncontrolled release of MC. If an incidental release of MC can be controlled by employees such as maintenance personnel at the time of release and in accordance with the leak/spill provisions required by subsection (f), it is not considered an emergency as defined by this standard.
Employee exposure means exposure to airborne MC which occurs or would occur if the employee were not using respiratory protection.
Methylene chloride (MC) means an organic compound with chemical formula, CH2Cl2. Its Chemical Abstracts Service Registry Number is 75-09-2. Its molecular weight is 84.9 g/mole.
NIOSH means the Director of the National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Physician or other licensed health care professional is an individual whose legally permitted scope of practice (i.e., license, registration, or certification) allows him or her to independently provide or be delegated the responsibility to provide some or all of the health care services required by subsection (j).
Regulated area means an area, demarcated by the employer, where an employee's exposure to airborne concentrations of MC exceeds or can reasonably be expected to exceed either the 8-hour TWA PEL or the STEL.
Symptom means central nervous system effects such as headaches, disorientation, dizziness, fatigue, and decreased attention span; skin effects such as chapping, erythema, cracked skin, or skin burns; and cardiac effects such as chest pain or shortness of breath.
Table 1.--Initial Determination Exposure Scenarios and Their Associated Monitoring Frequencies
Exposure scenario | Required monitoring activity |
Below the action level and at or below the STEL. | No 8-hour TWA or STEL monitoring required. |
Below the action level and above the STEL. | No 8-hour TWA monitoring required; monitor STEL exposures every three months. |
At or above the action level, at or below the TWA, and at or below the STEL. | Monitor 8-hour TWA exposures every six months. |
At or above the action level, at the STEL. | Monitor 8-hour TWA exposures every six months and monitor STEL exposures every three months. |
Above the TWA and at or below the STEL. | Monitor 8-hour TWA exposures every three months. In addition, without regard to the last sentence of the note to subsection (d)(3), the following employers must monitor STEL exposures every three months until either the date by which they must achieve the 8-hour TWA PEL under subsection (n) of this section or the date by which they in fact achieve the 8-hour TWA PEL, whichever comes first: employers engaged in polyurethane foam manufacturing; foam fabrication; furniture refinishing; general aviation aircraft stripping; product formulation; use of MC-based adhesives for boat building and repair, recreational vehicle manufacture, van conversion, or upholstery; and use of MC in construction work for restoration and preservation of buildings, painting and paint removal, cabinet making, or floor refinishing or resurfacing |
Above the TWA and above the STEL. | Monitor 8-hour TWA exposures and STEL exposures every three months. |
Note to subsection (d)(3): The employer may decrease the frequency of 8-hour TWA exposure monitoring to every six months when at least two consecutive measurements taken at least seven days apart show exposures to be at or below the 8-hour TWA PEL. The employer may discontinue the periodic 8-hour TWA monitoring for employees where at least two consecutive measurements taken at least seven days apart are below the action level. The employer may discontinue the periodic STEL monitoring for employees where at least two consecutive measurements taken at least seven days apart are at or below the STEL.
Note to subsection (e)(3): An employer who has implemented all feasible engineering, work practice and administrative controls (as required in subsection (f)), and who has established a regulated area (as required by subsection (e)(1)) where MC exposure can be reliably predicted to exceed the 8-hour TWA PEL or the STEL only on certain days (for example, because of work or process schedule) would need to have affected employees use respirators in that regulated area only on those days.
Note to subsection (f)(3)(B): See Appendix A for examples of procedures that satisfy this requirement. Employers covered by this standard may also be subject to the hazardous waste and emergency response provisions contained in § 5192(q).
Note to subsection (h)(3): See Appendix A for examples of disposal procedures that will satisfy this requirement.
Note to subsection (j)(5)(A): See Appendix B for an example of a medical and work history format that would satisfy this requirement.
Note to subsection (j)(5)(C): See Appendix B for information regarding medical tests. Laboratory surveillance may include before- and after-shift carboxyhemoglobin determinations, resting ECG, hematocrit, liver function tests and cholesterol levels.
Note to subsection (j)(6)(D): See Appendix B for examples of tests which may be appropriate.
Note to subsection (j)(9)(B): The written medical opinion may also include information and opinions generated to comply with other Title 8 health standards.
Note to subsection (m)(4)(A): All records required to be maintained by this section may be kept in the most administratively convenient form (for example, electronic or computer records would satisfy this requirement).
Cal. Code Regs. Tit. 8, § 5202
2. Change without regulatory effect amending subsection (n)(1) filed 2-3-98 pursuant to section 100, title 1, California Code of Regulations (Register 98, No. 6).
3. Editorial correction of subsection (b) (Register 98, No. 6).
4. Amendment of former subsections (g)(1)-(g)(7)(B) including subsection renumbering and relettering resulting in newly designated subsections (g)(1)-(g)(4)(B) filed 8-25-98; operative 11-23-98 (Register 98, No. 35).
5. Amendment of subsection (o) and repealer of subsections (o)(1)-(4) filed 7-6-99; operative 8-5-99 (Register 99, No. 28).
6. Amendment filed 7-29-99; operative 7-29-99. Submitted to OAL for printing only pursuant to Labor Code section 142.3(a)(3) (Register 99, No. 31).
7. Amendment of subsection (g)(3), new subsections (g)(3)(A)-(B) and repealer of subsections (g)(4)-(g)(4)(B) filed 3-6-2007; operative 3-6-2007. Submitted to OAL for printing only pursuant to Labor Code section 142.3(a)(3) (Register 2007, No. 10).
8. Editorial correction of subsections (g)(1)(D) and (g)(2)(A) (Register 2008, No. 6).
9. Amendment of subsection (k) and new subsections (k)(1)-(2) filed 5-6-2013; operative 5-6-2013 pursuant to Labor Code section 142.3(a)(4)(C). Submitted to OAL for printing only pursuant to Labor Code section 142.3(a)(4) (Register 2013, No. 19).
10. Amendment of subsection (k) and new subsections (k)(1)-(2) refiled 11-6-2013; operative 11-6-2013 pursuant to Labor Code section 142.3(a)(4)(C). Submitted to OAL for printing only pursuant to Labor Code section 142.3(a)(4) (Register 2013, No. 45).
11. Repealer of 11-6-2013 order by operation of law 5-6-2014 pursuant to Labor Code 142.3 (Register 2014, No. 19).
12. Amendment of subsection (k) and new subsections (k)(1)-(2) filed 5-5-2014; operative 5-6-2014 pursuant to Government Code section 11343.4(b)(3) (Register 2014, No. 19).
Note: Authority cited: Sections 142.3, 9020, 9030 and 9040, Labor Code. Reference: Sections 142.3, 9004(d), 9009, 9020, 9031 and 9040, Labor Code.
2. Change without regulatory effect amending subsection (n)(1) filed 2-3-98 pursuant to section 100, title 1, California Code of Regulations (Register 98, No. 6).
3. Editorial correction of subsection (b) (Register 98, No. 6).
4. Amendment of former subsections (g)(1)-(g)(7)(B) including subsection renumbering and relettering resulting in newly designated subsections (g)(1)-(g)(4)(B) filed 8-25-98; operative 11-23-98 (Register 98, No. 35).
5. Amendment of subsection (o) and repealer of subsections (o)(1)-(4) filed 7-6-99; operative 8-5-99 (Register 99, No. 28).
6. Amendment filed 7-29-99; operative 7-29-99. Submitted to OAL for printing only pursuant to Labor Code section 142.3(a)(3) (Register 99, No. 31).
7. Amendment of subsection (g)(3), new subsections (g)(3)(A)-(B) and repealer of subsections (g)(4)-(g)(4)(B) filed 3-6-2007; operative 3-6-2007. Submitted to OAL for printing only pursuant to Labor Code section 142.3(a)(3) (Register 2007, No. 10).
8. Editorial correction of subsections (g)(1)(D) and (g)(2)(A) (Register 2008, No. 6).
9. Amendment of subsection (k) and new subsections (k)(1)-(2) filed 5-6-2013; operative 5-6-2013 pursuant to Labor Code section 142.3(a)(4)(C). Submitted to OAL for printing only pursuant to Labor Code section 142.3(a)(4) (Register 2013, No. 19).
10. Amendment of subsection (k) and new subsections (k)(1)-(2) refiled 11-6-2013; operative 11-6-2013 pursuant to Labor Code section 142.3(a)(4)(C). Submitted to OAL for printing only pursuant to Labor Code section 142.3(a)(4) (Register 2013, No. 45).
11. Repealer of 11-6-2013 order by operation of law 5-6-2014 pursuant to Labor Code 142.3 (Register 2014, No. 19).
12. Amendment of subsection (k) and new subsections (k)(1)-(2) filed 5-5-2014; operative 5/6/2014 pursuant to Government Code section 11343.4(b)(3) (Register 2014, No. 19).