1. Methylene Chloride (MC)

2. Familiarization with MC
MC is used as a solvent, especially where quick evaporation is needed
Methylene chloride dissolves oils, fats, waxes, resins, rubber 1a

3. Familiarization with MC
Methylene chloride is used:
in paint strippers
as an ingredient in adhesives
as a degreasing agent
in propellant mixtures for aerosols
as an extracting agent in the pharmaceutical industry
as a blowing agent in polyurethane foam manufacture 1b

4. Training requirements
How to detect the chemical’s presence or release
The physical and health hazards of the chemical 2a

5. Training requirements
Safe work practices
Emergency procedures
Personal protective equipment 2b

6. Training requirements
The hazard communication program
Chemical labeling
How to use MSDSs 2c

7. Training requirements
Training is required under OSHA’s Hazard Communication standard
Training on MC is required before, or at the time of initial assignment to a job involving potential exposure to MC 2d

8. Training requirements
Hazard communication training must include the hazards of:
cancer
cardiac effects
central nervous system effects
liver effects
skin and eye irritation 2e

9. Training requirements
In addition to HazCom training, you need to know:
the requirements of the MC standard
the information that is available for MC
how to access or obtain copies of the standard and its appendices 2f

10. Training requirements
When exposures may be above the action level (12.5 ppm as an 8-hour TWA), you need to know:
quantity
location
manner of use
release
storage locations 2g

11. Training requirements
Specific operations in our workplace that could result in exposure to MC 2h

12. Training requirements
Employees who are exposed above the action level or the STEL (125 ppm for any 15-minute sampling period) may need to be re-trained
Changes in the workplace can also trigger re-training 2i

13. Physical hazards Methylene chloride:
is a clear colorless liquid with a chloroform-like odor
is only slightly soluble in water and mixes completely with most solvents
evaporates very quickly
vapors are heavier than air 3a

14. Physical hazards
MC forms flammable vapor/air mixtures at temperatures at or above 212 degrees F
When MC is involved in a fire, it decomposes into highly toxic and irritating chemicals 3b

15. Physical hazards
Fires and explosions may result if MC comes into contact with strong oxidizers, caustics, and chemically active metals
Heat and moisture contribute to the instability of MC 3c

16. Health hazards
The primary route of entry for MC is inhalation of its vapors
MC can also be ingested or absorbed by the skin
Direct contact with the liquid is irritating to the eyes/skin 4a

17. Health hazards
Health hazards can be either acute (short-term) or chronic (long-term)
The effects of long-term overexposure to MC may include cancer 4b

18. Health hazards
There is evidence that MC can have adverse effects on the heart, central nervous system, and liver 4c

19. Material Safety Data Sheets
The Hazard Communication standard requires MSDSs for products that contain hazardous materials 5a

20. Material Safety Data Sheets
When the product contains MC, make sure you are familiar with its health hazards in regards to:
cancer
cardiac effects
central nervous system effects
liver effects
skin and eye irritation 5b

21. Material Safety Data Sheets
MSDSs provide other useful information about how to handle the product and protect yourself from its hazards 5c

22. Labeling
All containers of MC must have legible labels that include the hazards
Labels must comply with the Hazard Communication standard 6a

23. Labeling
The label’s legend can be similar to the following: 6b

24. Exposure limits Exposures to airborne MC must be at safe levels
An employee’s exposure is determined without the use of a respirator
Exposures are given in parts per million (ppm) 7a

25. Exposure limits OSHA has set safe exposure limits as follows:
25 ppm as an 8-hour Time Weighted Average Permissible Exposure Limit (TWA PEL)
125 ppm as a 15-minute Short Term Exposure Limit (STEL) 7b

26. Exposure limits
The action level is 12.5 ppm as an 8-hour TWA 7c

27. Monitoring
When MC is present in the workplace, the employer must determine each employee’s exposure
One or more samples can be used to represent the exposures of several employees 8a

28. Monitoring The employer has to conduct initial monitoring unless:
there is objective evidence that airborne concentrations of MC will not reach the action level or STEL 8b

29. Monitoring The employer has to conduct initial monitoring unless:
employees are exposed to MC less than 30 days per year
adequate monitoring results were obtained in the year before the MC rule was effective (within 12 months prior to April 10, 1997) 8c

30. Monitoring
Periodic air monitoring must be conducted, depending on the results of the initial monitoring
Monitoring may need to be done as frequently as every three months 8d

31. Monitoring
Employees or their representatives have the right to observe any exposure monitoring
Anyone who is an observer must wear all necessary PPE and protective equipment 8e

32. Monitoring
Observers must follow all safety rules and procedures for the area
Employees must be informed of the monitoring results within 15 working days after the employer receives them 8f

33. Monitoring
The written notification of the results must include corrective actions being taken to reduce any exposures to below the 8-hour TWA PEL or STEL 8g

34. Medical screening/surveillance
Guidelines for the medical screening and surveillance program are in Appendix B of the standard
Initial screening is provided before initial assignment 9a

35. Medical screening/surveillance
Screening is conducted at no cost to the employee, without loss of pay, and at a reasonable time and place 9b

36. Medical screening/surveillance
Medical screening and surveillance will be provided for a worker whose exposure to MC is:
at or above the action level on 30 or more days per year
above the 8-hour TWA PEL or STEL for 10 days or more per year 9c

37. Medical screening/surveillance
Medical screening & surveillance will be provided for a worker whose exposure to MC is:
above the 8-hour TWA PEL or STEL for any period of time if the employee has been identified as being at risk from cardiac disease or any other serious MC related health condition 9d

38. Medical screening/surveillance
Medical screening & surveillance will be provided for a worker whose exposure to MC is due to an emergency involving MC 9e

39. Medical screening/surveillance
Continuing medical screening and surveillance is provided as follows:
Employees 45 or older will receive annual periodic medical surveillance
Employees under 45 will receive periodic medical surveillance every 36 months 9f

40. Medical screening/surveillance
A medical examination and appropriate tests are provided upon termination of employment if six months or more have elapsed since the last physical examination 9g

41. Medical screening/surveillance
A medical screening includes a baseline health questionnaire that emphasizes:
Neurological symptoms
Skin conditions
History of hematologic or liver diseases
Signs or symptoms of congestive heart disease 9h

42. Medical screening/surveillance
A medical screening includes a baseline health questionnaire that emphasizes:
Risk factors for heart disease
MC exposure
Work practices used
PPE 9i

43. Medical screening/surveillance
The physician issues a written medical opinion no more than 30 days after the examination
The written opinion is provided to both the employer and the employee 9j

44. Medical screening/surveillance
The information in the written opinion is limited to:
Occupationally pertinent results 9k

45. Medical screening/surveillance
A medical opinion concerning whether exposure to MC may contribute to or aggravate the employee’s existing cardiac, hepatic, neurological, or dermal disease 9l

46. Medical screening/surveillance
A medical opinion as to whether the employee has any other medical condition(s) that would place the employee’s health at increased risk from exposure to MC
Recommended limitations on the employee’s exposure to MC 9m

47. Medical screening/surveillance
A statement that the employee has been informed of the health risks associated with MC exposure
A statement that the employee has been informed of the results of the medical evaluation 9n

48. Temporary medical removal protection benefits
In some situations, physicians can recommend that an employee be removed from exposure to MC
10a

49. Temporary medical removal protection benefits
When exposure to MC is determined to aggravate an employee’s existing condition, medical removal protection benefits are in order
10b

50. Temporary medical removal protection benefits
The employer can either:
transfer the employee to comparable work where MC exposure is below the action level; or
remove the employee from MC exposure
10c

51. Temporary medical removal protection benefits
Temporary medical removal protection benefits include maintaining the earnings, seniority, and other employment rights and benefits
10d

52. Temporary medical removal protection benefits
If the employee is not exposed above the 8-hour TWA PEL, specific medical evidence must be cited before the employer is required to provide temporary medical removal protection benefits
10e

53. Temporary medical removal protection benefits
The employer can stop providing medical removal protection benefits at the earliest of the following:
10f

54. Temporary medical removal protection benefits
Six months
Upon receipt of a medical determination that the employee’s exposure will no longer aggravate the medical condition
Upon receipt of a medical determination concluding that the employee can never return to MC exposure
10g

55. Engineering controls Examples of engineering controls include:
dilution ventilation
local exhaust ventilation
enclosure of the operation
11a

56. Engineering controls
Engineering controls and work practices must reduce employee exposure to or below the 8-hour TWA PEL and STEL
11b

57. Engineering controls
When this is not feasible, engineering controls and work practices should reduce exposures to the lowest achievable levels
11c

58. Work practice controls
Work practices are used with engineering controls to reduce exposures to or below the 8-hour TWA PEL and STEL
12a

59. Work practice controls
Never eat, drink, or smoke where MC is used, stored, or handled. Also, do not keep food, beverages, or smoking materials in these areas
12b

60. Work practice controls
Keep containers tightly closed
Protect containers from damage
Store containers in a cool, dry, and well-ventilated area
12c

61. Work practice controls
Store containers away from direct sunlight, heat sources, and acute fire hazards
Avoid contact with strong oxidizers, caustics, and chemically active metals
12d

62. Work practice controls
Dispose of waste materials promptly and properly
A schedule of job rotation cannot be used as a work practice to limit or reduce exposure
12e

63. Respiratory protection
Respirators must be used:
while an employee’s exposure exceeds the 8-hour TWA PEL or STEL
while feasible engineering and work-practice controls are being installed or implemented
13a

64. Respiratory protection
Respirators must be used:
when feasible engineering and work practice controls are not sufficient to reduce exposures to or below the 8-hour TWA PEL or STEL
during work operations where engineering and work practice controls are infeasible
during emergencies
13b

65. Respiratory protection
If the right type of respirator is not being used, employees are not being adequately protected
In most cases, the standard requires that atmosphere-supplying respirators be used
13c

66. Respiratory protection
The only time that the use of a negative-pressure air-purifying respirator is allowed is during an emergency escape
The odor of MC is not a reliable warning of respirator malfunction for respirator wearers
13d

67. Respiratory protection
Respirator use must follow requirements in OSHA’s standard on Respiratory Protection
13e

68. Personal protective equipment
When protective equipment is required, it must be worn
PPE must be provided at no cost to the employee
14a

69. Personal protective equipment
Appropriate PPE includes, but is not limited to:
impervious chemical resistant clothing
gloves that are resistant to MC
splash-proof safety goggles
face shields (8-inch minimum)
14b

70. Personal protective equipment
Any protective clothing that becomes wet with liquid MC should be removed immediately and not reworn until the employer has ensured that it is fit for reuse
14c

71. First Aid
In the event of an emergency, institute first aid procedures and get appropriate medical assistance
For eye contact, flush with large amounts of clean water, and get medical attention immediately
15a

72. First Aid
For skin contact, remove all contaminated clothing and flush the affected area with large amounts of clean water
For inhalation of large amounts of MC vapor, move the person to fresh air immediately
15b

73. First Aid Get medical attention as soon as possible
Keep the affected person warm and at rest
15c

74. First Aid
If breathing has stopped, perform rescue breathing/cardiopulmonary resuscitation
15d

75. Leaks and spills
In areas where spills may occur, make provisions to contain any spills, and to safely dispose of any MC-contaminated waste materials
Incidental leaks must be repaired
16a

76. Leaks and spills
Incidental spills must be cleaned up by employees who are trained in cleanup, and who are using appropriate PPE
16b

77. Leaks and spills If MC has spilled or leaked:
remove all ignition sources
ventilate the area of the spill or leak
either collect the material for reclamation or absorb it in vermiculite, dry sand, earth, or a similar material
16c

78. Leaks and spills Dispose of contaminated material properly
Response to emergency releases of MC is covered by HAZWOPER
16d

79. Regulated areas
A regulated area is one where airborne concentrations of MC exceed or can reasonably be expected to exceed either the:
8-hour TWA PEL (25 ppm); or
STEL (125 ppm)
17a

80. Regulated areas
The regulated area is marked to establish its boundaries
Only authorized persons may have access to regulated areas
17b

81. Regulated areas
While in a regulated area, workers are not to do any non-work activities that could increase their dermal or oral MC exposure
Each person who enters a regulated area must be supplied with a respirator
17c

82. Regulated areas
The respirator must be used whenever the MC exposures are likely to exceed the 8-hour TWA PEL or STEL
17d

83. Marking regulated areas
Regulated areas are marked in any manner that adequately establishes and alerts employees to the boundaries
Movable signs, temporary barriers, or a system of warning lights can be used
18a

84. Marking regulated areas
A sample sign legend could look like:
18b

85. Standard availability
Any employees with jobs that involve the potential for exposure to MC need to know how they can access or obtain a copy of the standard and its appendices
19a