Laboratory Ergonomic Stressors
This laboratory procedure is highly repetitive and involves a variety of risk factors. Cumulative Trauma Disorders (CTD) or MSDs may occur when a laboratory worker pipettes for two hours a day or longer on a continuous basis.
Associated Risk Factors:
- Repetitive motion of the hands, forearm and thumb, or fingers
- Pinch grip when handling pipette tips, or opening vials
- Bending and twisting of the wrist
- Working with "winged" elbows (elbow held at an elevated position away from the body)
- Neck bent forward or to the side and/or jutted chin
- Awkward and static postures
- Excessive force of the thumb
- Standing for long periods of time
Work Smart, eliminate/reduce the impact of laboratory ergonomic stressors.
- Perform your work only at appropriate heights.
- Alter continuous repetitive pipetting by performing other tasks, or take frequent small rest breaks every 20 minutes.
- Be sure to work with wrists in neutral positions (straight).
- Adjust height and position of sample holders, solution container, waste receptacle to prevent twisting and bending of wrist, neck and rolled shoulders.
- Reduce shoulder strain, avoid working with winged elbows/arms.
- Use short pipettes, shorter waste receptacles for used tips, to reduce reaching.
- Use electronic pipettes for highly repetitive pipetting tasks to reduce/eliminate contact pressure on thumb.
- Ensure proper lower back and thigh support, by using adjustable stools or chairs with built-in foot and arm rest.
- Avoid standing for long periods. If standing is unavoidable, use Anti-Fatigue Mats.
- Work at appropriate heights to minimize twisting of the neck and torso.
- Replace manually operated pipettes with electronic ones for larger workloads.
- Make sure head and shoulders are kept in neutral position.
- Avoid elevating arms and elbows above shoulder for lengthy periods to prevent static work of arm, and shoulder strain
- Task sharing is another way to reduce the impact of risk factor associated with pipetting.
Working in Biological Safety Cabinet (BSC's) or fumehoods requires laboratory personnel to assume a variety of awkward postures due to limited work access, which restrict arm movement, and therefore significantly increase the amount of stress on joints of the upper limbs, neck, and back.
Associated Risk Factors:
- Repetitive motions of the hands, wrist, and forearms, especially when pipetting is involved
- Constrained knee and leg space, especially in fume hoods and older BSCs
- Contact pressure on the forearms, wrists and knees, or legs
- Awkward and static posture of the neck, torso, legs, arms and wrists
- Constrained body position, overloading muscles, tendons, and joints in asymmetrical manner
- Working with elbows winged
- Prolonged standing in unnatural positions or in restricted postures
- Prevent extended reaching, place materials as close as possible
- Perform your work at least six inches back into the hood or BSC to maintain optimal airflow containment for material and personal protection.
- Always assume a proper posture. Use only adjustable chair or stool with built-in foot and arm rest.
- Avoid contact pressure (forearm and wrists contact with sharp edges). Apply foam padding to the front sharp edge of the fumehood/BSC to reduce pressure concentration.
- If you perform work in a fumehood or BSC while standing for prolonged periods of time, use an anti-fatigue mat and footrest to reduce muscle, joint, and spinal fatigue.
- Take short breaks to alter repetitive forearm and wrist motion, relieve joint pressure and contact pressure caused by sharp edges.
- Reduce eye strain and awkward posture by keeping viewing window of hood/BSC clean, and line of sight unobstructed.
- Make sure hood/BSC lighting is working properly, good and proper lighting help reduces eye strain.
- Raise cabinet couple inches upwards to create a more comfortable leg and thigh clearance.
- Purchase only ergonomically designed equipment and furniture.
Operating a microscope for long hours puts much strain on the neck, shoulders, eyes, lower back, and arms/wrists.
Associated Risk Factors:
- Awkward and static posture of the lower back
- Lack of adequate leg and knee clearance under work table
- Working with elbows winged
- Pinch grip when adjusting binocular eyepiece
- Wrist and palm contact pressure in the carpal tunnel area
- High repetition
- Eye strain and fatigue
- Awkward and static posture of the neck and head
- Do not work with elbows winged. Keep elbows close to sides, below 45 degree angle.
- Make sure to work with wrists in neutral (straight) position. Avoid forearm and wrist contact pressure. Pad sharp edges with foam, or pad wrists and forearms to reduce pressure.
- Make sure leg and knee clearance under work bench is adequate.
- Always assume proper sitting position, Ensure proper lower back and thigh support.
- Ensure that feet are flat on floor or supported by footrest.
- Use only adjustable chair or stool with built-in foot and forearm rest.
- Avoid raising shoulders and bending neck while looking through microscope's eyepiece.
- Adjust microscope eyepiece's height to allow head and neck proper(upright)neutral posture.
- Position microscope as close as possible towards you to ensure upright head position.
- Use or purchase extended eyetube and/or variable height adapter to achieve proper neck and head position.
- Prevent repetition, and alter prolonged awkward posture. Take adequate small breaks, or perform other job tasks that requires less repetition, rest your eyes, neck, and shoulders.
- Use video display terminal when appropriate to view sample, and reduce eye and neck strain.
- Make sure scopes remain clean all the time, and lighting is of proper intensity.
When used inappropriately, laboratory workbenches can expose researchers to a variety of hazardous conditions or ergonomic risk factors depending on the laboratory procedure being used. Most workbenches at the University are of fixed heights and cannot be modified (raised or lowered). In general they are the same height and were designed for light to slightly heavy work. Using a laboratory workbench as a computer workstation is an example of inappropriate use, since it forces the worker to assume a variety of awkward postures and may increase the likelihood of acquiring MSD.
- If workbench height is above elbow height, between 37and 43 inches, use for precision work.
- If workbench height is just below elbow height, between 34 and 37 inches, use for light work.
- If workbench height is below elbow, between 28 and 35 inches, use for heavy work.
- Always assume proper sitting or standing neutral posture.
- When sitting, use only adjustable stool or chair with built-in foot and arm rest to insure lower back, thigh, and feet support.
- If leg clearance is not available, workbench must not be used for work requiring using a stool. Otherwise, create leg room under the bench by removing drawers.
- When standing for extended periods of time, use anti-fatigue mats and a foot rest to reduce joint strain and muscle fatigue.
- Remove drawers, supplies and other materials underneath workbenches to provide leg room.
- Take frequent small breaks to alter repetition, body awkward posture, and muscle static work.
Manual rotary microtome use in histology laboratories requires performing many repetitive functions. In the course of one day, a laboratory technologist may use between 40 and 50 cassettes or blocks a day, hence turning the microtome wheel for at least a 1000 time. This is not only repetitive work, but turning microtome's wheel also requires force or forceful exertion. Other repetitive microtome-related functions such as replacement of specimens and use of trimming wheel increase the probability of acquiring MSD.
- Place microtome on appropriate workbench (appropriate height). Take into consideration the way work will be performed (standing or sitting).
- If sitting is required, make sure the workbench allows enough clearance for leg and thighs.
- Use only adjustable chair or stool with built-in foot and arm rest.
- Make sure sharp edges are not an issue.
- Protect wrists and forearms from contact pressure. Pad sharp edges.
- Use less force when turning handwheel.
- Take frequent small breaks from microtome work every 20 minute.
- If economically feasible, replace manual rotary microtome with an automatic one.