- Index of Cal/OSHA services
- File a workplace safety complaint
- Learn about worker rights
- Obtain a free consultation
- Report an accident or injury
DOSH ergonomics proposal 1994
(a) Scope and Application.
(1) Section 5110 applies to all places of employment and establishes minimum requirements for controlling occupational exposure to the risk of developing cumulative trauma disorders (CTDs).
(2) The purpose of section 5110 is to provide guidance on and make more specific the requirement to address CTD risk through the Injury and Illness Prevention Program mandated by section 3203. Employers may implement the provisions of section 5110 independently or as part of the Injury and Illness Prevention Program required by Section 3203
(3) All employers shall comply with subsections (c), (d), (f)(1) and (f)(2) within two years, and with subsections (e) and (f)(3) within three years.
(1) Administrative controls. Procedural CTD risk control measures which include, but are not limited to, redesign of work duties, adjustment of work pace, and use of rest periods or different work duties to interrupt activities which pose a CTD risk to the employee.
(2) Cumulative trauma disorder (CTD). Any physical disorder that develops from or is aggravated by the cumulative application of biomechanical stress to tissues and joints, including but not limited to, bursitis, ligament sprains, muscle strains (e.g., neck-tension syndrome), nerve entrapment (e.g., carpal tunnel syndrome), stenosing tenosynovitis (e.g., trigger finger), tendon-related disorders (e.g., de Quervain's), and hand-arm vibration syndrome.
(3) CTD risk. The presence of one or more of the following factors in work activity in such a manner and to such an extent that a CTD is substantially likely to result:
(A) Frequency, i.e., the rate at which specific physical motions or exertions are repeated;
(B) Force, i.e., physical exertion by or pressure applied to any part of the body;
(C) Duration, i.e., the length of any period of work activity which poses a CTD risk;
(D) Posture, i.e., the position of a body part during work activity;
(E) Exposure to localized or whole-body vibration; and
(F) Exposure of hands and feet to extreme cold temperatures which cause discomfort.
(4) CTD symptom. Any of the following, when persisting or recurring and reasonably likely to be work-related: pain from movement, from pressure, or from exposure to cold or vibration, except when the pain is due to an acute injury to the back or an extremity, an instantaneous event, or other disorder not related to CTD risk factors (e.g., burn, abrasion, splinter, slip and fall); change in skin color (e.g. skin turns blue, or abnormally white or red) on exposure to cold or vibration; numbness or tingling in an arm, leg, or digit, especially in fingertips at night; decreased range of joint motion; decreased grip strength; swelling of a joint or part of an arm, leg, or digit.
(5) Engineering controls. Engineered CTD risk control measures which include, but are not limited to:
(A) Devices such as adjustable work stations, tables, chairs, equipment, and tools; and
(B) Physical modifications to work stations, equipment, tools, production processes, or any other aspect of the work environment.
(6) Feasible engineering controls, administrative controls and PPE. Those control measures which are technologically capable of being implemented, except where they would impose an undue hardship, including economic hardship, on the employer.
(7) Personal protective equipment. Clothes, padding, gloves, devices, equipment, or other items worn on or attached to the body, and used for the purpose of controlling CTD risk.
(8) Splint. A device worn on or attached to a limb which keeps a body part in a fixed position.
(9) Visual display terminal (VDT). Any device or set of devices not designed for hand held use, which involves use of a keyboard, mouse, or other mechanical data entry device, and a cathode ray tube or other electronic devices for entry or display of data such as words, numbers, and symbols.
(10) VDT operator. An employee who routinely performs repetitive keystroking at a VDT for a cumulative total of four or more hours per day and 20 or more hours per week.
(11) Worksite. The location of an employer's operations at which the employee customarily and normally works.
(c) Procedures for Gathering Preliminary Information on CTD Risk.
(1) One-Time Records Review. Each employer shall perform a one-time review of the employer's existing records for the three year period ending on the date the review is initiated, to determine whether employees have reported symptoms of or been diagnosed with any CTD, or whether the records indicate that a CTD risk exists at the workplace. The records to be reviewed shall include all records maintained pursuant to 8 CCR section 14320 et seq. (OSHA "200 log" records), and all available safety, and workers' compensation records. Each employer shall also review available medical records generated within the scope of the employment relationship during the one-year period ending on the date the review is initiated.
(2) Reporting Procedure.
(A) Each employer shall implement an effective procedure that encourages employees to report, orally or in writing, CTD symptoms or CTD risk without fear of reprisal or discrimination.
(B) If an employee who makes an oral report is unable to write, the employer shall reduce the report to writing.
(C) All written reports shall be maintained for a period of at least 3 years.
(d) Worksite Evaluation.
(1) When Required. Each employer shall promptly perform a worksite evaluation whenever:
(A) An employee reports a CTD symptom, as defined in section 5110(b)(4), which is reasonably likely to be work-related.
(B) An employee is diagnosed with a work-related CTD, as indicated by records the employer must review under section 5110(c)(1) or any other record known to the employer; or
(C) The employer acquires factual information that identifies CTD risk in a specific work activity in the employer's workplace.
Note: Appendix A of section 5110 may be used for guidance in identifying and evaluating CTD risk.
(2) Updating Worksite Evaluations.
(A) Worksite evaluations need not be repeated. However, they shall be updated within a time frame reasonably calculated to provide the earliest effective evaluation, whenever:
(i) Control measures are implemented which affect any work activity subject to worksite evaluation;
(ii) New processes, procedures, equipment, or work activities, which are substantially likely to add to or increase CTD risk in previously evaluated activities, are introduced into the workplace; or
(iii) The employer acquires new factual information about a specific work activity in the employer’s workplace indicating that the most recent worksite evaluation may be deficient;
(B) Worksite evaluation updates may be limited to addressing the specific condition making an update necessary.
(3) Components of Worksite Evaluation. Worksite evaluation shall include the following:
(A) Asking employees whose activities are subject to worksite evaluation if they have recently experienced or are experiencing CTD symptoms related to CTD risk. The inquiry shall include finding out what the symptoms are, their severity and duration, and which work activities, if any, the employee associates with the symptoms.
(B) Identifying the specific work activities, if any, that are likely contributors to the CTD risk, symptom, or diagnosis which necessitated the worksite evaluation. This determination shall be based on observation of job tasks and asking employees about how they perform their work. Employees with substantially similar work activities may be evaluated as a group to avoid duplication, provided that the effectiveness of the evaluation is not compromised.
(C) Identifying and evaluating changes that can be made, if any, to reduce CTD risk in the activities identified pursuant to subsection (d)(3)(B).
(D) A description of the control measures to be implemented, if any, including a schedule for their design, implementation, and evaluation. An employer shall keep the schedule appropriately updated.
Note No. 1: Worksite evaluations of nonfixed workstations or worksites may be limited to evaluation of tool and machinery use and tasks involving manual lifting.
Note No. 2: Appendix A may be used as a guide in performing worksite evaluations.
(4) Scope of Worksite Evaluation.
(A) When worksite evaluation is required because an employee reports CTD symptoms or is diagnosed with a CTD, the evaluation shall address the work activities of that employee.
(B) When worksite evaluation is required because a CTD risk is identified, the evaluation shall address the employees known to be exposed to the CTD risk.
(5) Documentation. All worksite evaluations, including updates, shall be recorded. These records shall be retained for a period of at least 3 years from the date the record is generated. The employer shall assure that all worksite evaluation records maintained pursuant to this section shall be made available upon request to employees, employee representatives, and the Division.
(e) Control Measures
Each employer shall use feasible engineering controls, administrative controls, and PPE as necessary to eliminate or reduce CTD risk. Control measures shall be deemed necessary when any work-related CTD risk causes or aggravates CTD symptoms.
Exception: For VDT operators, compliance with the specifications of Appendix B will fully meet the requirements of subsection (e)(1), unless a specific employee's physical attributes or physiological condition make further feasible control measures necessary. Methods of compliance other than those specified by Appendix B may be used where they provide effective protection.
(2) All control measures required by section 5110 shall be implemented in a timely manner based on the severity of the hazard, but need only be implemented to an extent and degree commensurate with the findings of an effective worksite evaluation.
(3) Use of PPE.
(A) PPE shall not be used as a substitute for feasible engineering or administrative controls.
Exception: PPE may be used where it provides protection at least as effective as the engineering and administrative controls otherwise required by subsection (e).
(4) Use of Splints. A splint shall not be used for protection against CTD risk unless used under the advice of a licensed physician or chiropractor as treatment for a CTD during the healing period, and it has been determined that the splint does not interfere with movement required for performance of work activities.
(1) Effective training shall be provided as required by subsections (f)(2) and (f)(3). Each employer shall document the training given, including the employee's name or other identifier, training dates, type(s) of training, and training providers. Documentation shall be maintained for at least three years.
Exception No. 1: Training provided before subsection (f) takes effect shall be deemed to comply with subsection (f) if the training otherwise meets the applicable requirements of subsections (f)(1), (f)(2), and (f)(3).
Exception No. 2: Employers who employ one or more temporary workers for periods of 90 days or fewer per year may comply with all training requirements for those employees by having them attend a brief, pre-job safety meeting. The meeting shall cover any job-specific CTD risks, safe work methods, and how to use the employer's reporting procedure. The discussion shall also include an opportunity for the employee to ask questions and receive answers about job safety.
(2) General training shall be provided to all employees and at least include:
(A) Awareness of the Symptoms and Consequences of CTDs. An explanation of the types and symptoms of upper and lower extremity CTDs, how CTDs occur, how their initial symptoms can be detected, and the physical limitations CTDs can cause.
(B) Awareness of CTD Risk Factors. An explanation of what CTD risk is, the types of medical conditions that can aggravate CTDs, and the types of occupational and non-occupational activities and postures that are associated with CTD risk.
(C) Awareness of Safe Work Methods. An explanation of methods and techniques to minimize CTD risk in the employee's work activities, including the correct and safe use of the equipment and tools which pose a CTD risk to the employee. See Appendix A for guidance.
(D) Reporting System. An explanation of the use and importance of the reporting procedure implemented pursuant to subsection (c)(1).
(3) Job-specific training shall be provided promptly upon completion of worksite evaluation to all employees whose work activities are required to be addressed by engineering controls, administrative controls, or PPE. If job-specific training is provided before implementation of engineering controls, the training shall be updated promptly upon implementation of engineering controls. Job-specific training shall at least include:
(A) Asking employees for ideas about minimizing CTD risk in their work activities;
(B) Demonstrating the correct and safe use of all equipment and tools which pose a CTD risk to the employee; and
(C) Reviewing all information from worksite evaluation which is relevant to the safe performance of the employee's work.
Exception: Job specific training is not required for any CTD risk addressed by engineering controls which are effective in the absence of employee instruction, provided the engineering controls are implemented promptly after completion of worksite evaluation.
APPENDIX A (Non-Mandatory)
Identification and Evaluation of CTD Risk
Note: This Appendix is for use as a guide to identifying and evaluating CTD risk in work activities. Section I gives examples of specific work activities that are especially prone to CTD risk. Other work activities may also involve CTD risk to the worker, so employers should not assume that activities listed in section I are the only activities that must be evaluated. Section II is a guide to evaluating CTD risk associated with repetitive activity, and Section III is a guide to evaluating CTD risk which is independent of repetitive activity.
I. High-risk activities. Where any of the following activities take place, there are likely to be one or more CTD risks that require evaluation:
A. Continuous use of the same tool or similar tools in construction, agricultural, or repair activities, or routine use of vibratory or pneumatic tools.;
B. Repetitive keystroking, where keystroking consists of manually striking or pressing a data-entry device such as a keypad or button;
C. Processing of meat, poultry, or seafood, e.g., butchering, scaling, shelling, plucking, cutting, trimming, processing, canning, packing, or loading;
D. Processing of agricultural products, e.g., sorting, washing, cutting, trimming, peeling, shelling, canning, packing, or loading;
E. Work where the pace of repeated motions or exertions is controlled by the speed of a mechanical or electronic device, e.g., auto assembly, telephone operator services, food processing, bottling, packaging, labelling, garment production or other fabric finishing;
F. Repetitive operation of a cash register or manual presentation of an object to a scanning device for the purpose of recording data.
G. Routine assumption of a crouched or stooped body posture.
H. Routine manual lifting, which should be evaluated using the most current NIOSH equation for the design and evaluation of manual lifting tasks. The evaluation should include calculation of the Recommended Weight Limit (RWL) and the Lifting Index (LI). A lifting manual task for which the lifting index is less than or equal to one is generally considered acceptable.
II. CTD Risk Associated With Repetitive Activity.
A. Identifying the Specific CTD Risks. The most important question to ask when identifying and evaluating CTD risk is whether or not repetitive activity is present. Repetitive activity can consist of at least seven
separate CTD risks:
1. The frequency at which the specific motion or exertion is repeated;
2. The amount of force used to perform the specific motions or exertions;
3. The duration of the repetitive activity;
4. The posture assumed while performing the repetitive activity;
5. The interval between repetitive motions or exertions, or between periods of repetitive activity, which is needed to prevent fatigue of the body parts performing the activity;
6. The presence of vibration while performing repetitive activity; and
7. Exposure of fingers and toes to extreme cold temperatures while performing repetitive activity.
Where repetitive activity is present, these CTD risks can occur together. But it is essential to identify each separately to ascertain which are the most hazardous and how each can be reduced. In general, the faster the frequency, the greater the force, the longer the duration, the more awkward or uncomfortable the posture--the more CTD risk the repetitive activity poses. Keep in mind that physical fatigue may be a sign that one or more of these CTD risk factors must be reduced, or that the repetitive activity does not allow a recovery time of sufficient length.
B. Evaluating Control Measures for Specific CTD Risks Involving Repetitive Activity.
1. General Considerations. Where repetitive activity is present, consider:
a. Reducing the frequency of repetition, i.e., how many times per second, minute, or hour a motion is repeated.
b. Reducing the total duration of the activity. Avoid reducing the duration of the activity by increasing the frequency of the motions or exertions.
c. Using different tasks or short breaks to interrupt periods of repeated activity. Introducing variety into the work routine usually results in greater interest and increased productivity.
d. Reducing the amount of force which is needed to perform the work.
e. Changing the body position necessary to perform the activity. Look for ways to improve the positioning of employees when performing work tasks, e.g., reducing the extent to which employees have to reach, stretch, or bend to perform a job task.
f. Reducing the time an employee must spend performing work in an awkward or uncomfortable position or posture.
2. Specific Examples.
a. If the repetitive activity is keystroking, consider providing
adjustable chairs and moveable keyboards, increasing leg room,
positioning the VDT screens at appropriate heights and distances from
the operator and other measures that result in greater physical comfort.
b. If the repetitive activity involves chopping or cutting, e.g., with a knife, scissors, etc., is the instrument being used the best for the job? Can the amount of force necessary to cut or chop be reduced by using a larger instrument, a smaller instrument, or an instrument of different shape or design? Is the instrument kept sharp at all times? Can bending of the wrist be reduced or made more comfortable by using a different instrument? If chopping or cutting is done against a surface, is the surface at the best height? Is there a way to make the surface adjustable so that the worker can choose what works best for him or her?
c. If the repetitive activity involves use of a hand tool, is the tool the best for the task? Will another tool require less force, allow the worker to use it more comfortably, or allow the work to be done with less repetitive activity? Can use of another device assist in supporting the weight of the tool? Is there a way to perform the task which will allow use of less hazardous tools?
III. CTD Risk Unrelated to Repetitive Activity.
A. Identifying the Specific CTD Risks. CTD risks can sometimes exist independent of repetitive motion. This means that while they may well occur in connection with repetitive activity, the risk they pose is independent of the specific motions being repeated. For example, improper seating and keyboard height for a computer operator may create a CTD risk because of the posture of the shoulders and neck that results. The posture is a CTD risk independent of the fact that the employee is engaged in repetitive keystroking; it arises because the employee must maintain the posture while performing the keystroking activity, not because of the keystroking activity itself. CTD risks which are independent of repetitive activity include prolonged static exertions, contact stress, prolonged assumption of awkward or uncomfortable postures, work with a tool or equipment which vibrates, and work associated with exposure of hands or feet to cold temperatures.
1. Static Exertions. Static exertions are a combination of two CTD risk factors, force and duration. Static exertions are exertions which require use of significant force by the body but do not result in significant movement of the body. Three examples of static exertions are (a) holding sheet rock in place while it is being nailed onto a ceiling; (b) holding a sack by hand or with a shoulder strap; and (c) squatting or stooping while harvesting or cultivating crops.
2. Contact Stress. Contact stress comes about from pressure being applied to a specific body part or tissue.
3. Assumption of Awkward or Uncomfortable Postures. Assumption of awkward postures often goes along with prolonged static exertions, although this is not always the case. The three examples given above could involve awkward posture and prolonged static exertion occurring together to magnify CTD risk. Standing at a work station for prolonged periods is another example.
4. Work with Vibrating Tools or Equipment. Vibration can be a problem for workers who use power tools or powered equipment, including tractors and trucks.
5. Work Involving Cold Temperatures. Exposure of fingers and toes to cold temperatures can constitute a CTD risk. In addition, the harmful effects of vibration can be intensified by simultaneous exposure to cold temperatures.
B. Evaluating Control Measures for Specific CTD Risks Unrelated to Repetitive Activity.
1. General Considerations.
a. Where static exertions are present, consider ways to reduce the amount of force needed for the exertion.
b. Where awkward or uncomfortable postures are present, consider ways to reconfigure the task. See section I.B.1.e., above.
c. Where vibration is present, consider ways to reduce contact with vibrating tools or equipment. If the repetitive activity involves forceful contact with or transmission of vibration to a body part, consider ways to reduce the amount of force or vibration. Also consider ways to pad surfaces which contact the body.
d. Where extremities are exposed to cold temperatures, consider ways to reduce exposure by heating the work environment, redirecting air flow, wearing protective clothing or gloves, or reducing exposure time.
2. Specific Examples.
a. If the job involves applying constant pressure to a work surface, such as scraping, grinding, sanding or buffing hard surfaces, can the worker use a heavier tool to deliver adequate pressure with less exertion? Does the need for pressure increase as the sanding or grinding pad becomes worn? If the job involves assumption of an awkward or uncomfortable posture, can the need to reach, stretch, bend or twist be reduced?
b. If the job involves use of a power tool which causes vibration, can the vibration be reduced by using another tool or can transmission of vibration to the body be reduced by the use of padding or isolators?
c. If the job involves entry into a cold environment or work with cold objects, such as storing items in cold storage lockers or packing frozen objects, can the body and/or the extremities be adequately protected by heating the surrounding environment or by using clothing and/or gloves?
Note: This Appendix is applicable to VDT operators who routinely perform repetitive keystroking at a VDT for a cumulative total of four or more hours per day and 20 or more hours per week.
I. VDT Workstation Criteria.
Note: Employers are cautioned that merely providing workstation equipment meeting the following criteria is not sufficient to protect against CTD risk. The equipment must be appropriate for the task and the employee must be properly trained to use it.
A. Seating for the workstation shall meet the following requirements:
1. Seating Height. The height of a seat shall allow the user to place feet firmly on a support surface.
2. Seat Depth. The maximum seat depth shall permit contact with the back rest in the lumber area and be designed to avoid pressure on the back side of the lower leg.
3. Seat Width. The minimum seat width shall be the thigh breadth of the seated person.
4. Seat Pan Angle. The seat pan angle of a chair shall generally ensure that the angle between the upper and lower leg, with the lower leg perpendicular to the floor, is between 60 and 100 degrees.
Exception. Where the seat pan is adjustable for angle and the employee can readily adjust it to a comfortable position, determinations of seat pan angle need not be made.
5. Angle between Seat Back and Seat Pan. The angle between the seat back and the seat pan shall permit the user to assume a working posture with a torso-to-thigh angle of at least 90 degrees.
Exception. Where the seat pan is adjustable for angle and the backrest is adjustable to angles ranging from behind the vertical position to forward of the vertical position, and the employee can readily adjust both to a comfortable position, determinations of the torso-to-thigh angle need not be made.
6. Backrest Height and Lumbar Support. The backrest provided shall have a width of at least 12 inches and assure support in the lumbar region.
7. Armrests. The minimum inside distance between armrests shall be equal to at least the clothed hip breadth of the user.
8. Forearm Supports. Forearm supports, if present, shall be removable if they are not adjustable.
B. The adjustment mechanisms for adjustable seat pans and backrests shall be readily operable by the user.
C. Working Posture.
1. VDT Screen. The VDT screen shall be positioned so that the entire primary viewing area of the screen is between zero and sixty degrees below the horizontal plane passing through the eyes of the operator.
2. Keyboard Height. The keyboard, in combination with the seating and the work surface, shall be positioned so that the operator, while seated in the most comfortable upright position, is able to operate the keyboard with his or her forearms, wrists, and hands in a position approximately parallel to the floor.
3. Work Surface Height. The height of the work surface shall provide adequate clearance under the work surface to accommodate the operator's legs in the position most comfortable for the operator.
D. VDT Accessories.
1. Document Holder. A document holder adjustable for placement, angle, and height shall be provided on request to any employee who types from documents.
2. Arm, Wrist and Foot Rests. Arm, wrist, and foot rests shall be provided upon the request of the operator. Wrist rests shall assist the operator in maintaining a neutral position of the hand and wrist while keying, and shall be padded and free of sharp edges. Arm rests shall not interfere with the operator's ability to relax the shoulders, operate the keyboard with hands, wrists, and forearms in a position approximately parallel to the floor, and move as close as desired to the keyboard.
E. Lighting. Lighting for VDT workstations shall be arranged to avoid glare and visual discomfort.
F. Glare. Glare shall be reduced to the extent feasible through any effective combination of one or more of the following methods: shielding windows with shades, curtains, or blinds; positioning the VDT screen so that it is at a right angle to the window producing the glare; fitting VDT screens with anti-glare devices which do not allow build-up of static electricity; and providing keyboards with surfaces finished to minimize reflection.
G. VDT Screens. VDT screens shall be clean, clear, and free of perceptible flicker.
II. Alternative Work. (For VDT operators who perform repetitive keystroking at a VDT for a cumulative total of four or more hours per day and twenty or more hours per week, during a routine work week.)
A. Each VDT operator shall be provided with alternative work for a cumulative period of at least 15 minutes during or immediately after each two-hour period of repetitive keyboard work. Where the pace of repetitive keyboard work is automated or controlled by a mechanical or electronic device, alternative work shall be provided for a cumulative period of at least five minutes during or immediately after each one-hour period of repetitive keyboard work.
B. The term "alternative work" means rest, a break of any kind, work which does not involve operation of a VDT and which will not duplicate the motions used to operate a VDT, or any combination of the above.