Laboratory Ergonomics

OHS Memo M3/07

To: All Heads of Department of the Science Area, Safety Office

The University has a range of laboratory environments and musculoskeletal issues sometimes arise in association with working activities within them. This guidance document is intended to assist in the application of ergonomic principles to common laboratory situations. It is not intended to be prescriptive. Please do not hesitate to contact the Occupational Health Service if you have any enquiries.

December 2007

Workplace ergonomics tends to be centred around office ergonomics, however laboratory ergonomics is just as important. This workplace setting poses many ergonomic risks to its users. Those who use microscopes and pipettes regularly are at risk of developing musculo-skeletal problems or exacerbating pre-existing ones. Working at laboratory benches and within safety cabinets can also pose problems. Factors such as; repetitive movements, forceful movements, awkward and static postures, can all contribute to the development of musculo-skeletal problems. Laboratory workers can control laboratory ergonomic risk factors by taking some simple measures which can help improve comfort, productivity and reduce the chances of developing health problems.

Microscopes

Sitting or standing for hours on end, bent over a microscope eyepiece is not an activity for which the body is well adapted. Poor posture and awkward positioning of the head, neck, shoulders, back, arms and wrists are the primary risk factors for musculo-skeletal problems that can affect microscope users. The following are some basic guidelines for achieving and maintaining neutral body posture and reducing the risks of developing health problems while using a microscope:

Try to avoid using a microscope for long periods in the day. Spread usage out over the day, avoiding long uninterrupted periods of usage. Short rest breaks (‘micro breaks’) should be taken every 20 minutes during continual usage.

To maintain an upright posture, don’t lean forward to look through the microscope. Instead, the position of the chair and/or microscope should be adjusted so that the user’s back is straight, the head is upright and eyes are looking directly into the eyepiece. Eyepieces should be in line with, or even extended over, the edge of the bench. There should be adequate space under the bench so that the user can pull the chair in close enough to the microscope so that their back is straight and supported by the chair backrest

Upper arms/elbows should be close to the body so that they are not outstretched and forearms should be supported where possible. If the latter is not feasible, regular rest breaks should then be taken.

Feet should rest firmly on the floor or on a footrest, and even pressure should be applied by the chair to the backs of the thighs. If footrests are not available, footrings on laboratory chairs can be used but should be adjusted so that feet are supported, legs are not hanging and the back is supported by the chair backrest.

Pipettes

Pipetting is one of the most common tasks performed by those working in laboratory settings. Again, this activity poses risk factors for the development of musculo-skeletal problems. These factors include; repetitive movements, forceful movements, particularly on the thumb and awkward postures which can affect the hands, wrists, arms and shoulders. The following are some basic guidelines for reducing the risks of developing health problems whilst pipetting:

Plan work so that pipetting can be interspersed with other tasks and ensure that short frequent rest breaks (‘micro breaks’) are taken every 20 minutes.

Organise bench so that there is enough space to carry out tasks and avoid twisting and stretching movements.

Aim to hold upper arms close to the body so that they are not outstretched. Although this is often difficult to achieve and maintain, the key is to try to avoid static postures and vary tasks as much as possible. The user may need to sit or stand to achieve this position.

Only use as much force as is needed to activate the pipette. Keeping pipettes clean and well maintained will help to ensure that they dispense easily with minimum force.

Use electronic pipettes for long runs of identical dispensing.

Factors to consider when choosing pipettes:


  • Length of pipette – the shorter, the better.
  • Plunger pressure – the lower, the better.
  • Pipette tips – use thin walled ones that fit correctly and are easy to eject.
  • Overall grip should feel comfortable.

Although electronic pipettes are more costly and often less versatile, they put less force on the thumb. Consider having a variety of pipettes available.

Safety Cabinets and Work Benches

These present similar ergonomic hazards which are mainly associated with lack of leg room and static positions. The following are some basic guidelines for reducing risks of developing health problems whilst working at safety cabinets and on work benches.

Use a suitable chair, i.e. a laboratory chair, which is higher than a standard office chair and has a footring. The chair seat pan, back rest and footring should be height adjustable and the back rest should be tilt adjustable.

Sit in a comfortable position with back supported by the chair back rest, legs supported on a high footrest or on the footring and forearms positioned horizontally over the work bench surface and not outstretched. Sit in close enough to the bench to achieve this posture. It is not always possible to avoid stretching of the arms and this is dependent on the tasks being carried out and materials being used.

Remove obstacles from under the work bench such as drawers, fridges, supplies etc, to provide appropriate leg room.

Perch stools can be used when leg room under the bench is limited, to aid appropriate height and posture when working at a safety cabinet or where individuals have to stand for long periods of time and can thus relieve strain on the back.

Position materials and equipment to be used frequently within easy reach in safety cabinets or on the work bench top to avoid unnecessary bending, twisting or stretching.

Ensure short frequent rest breaks (‘micro breaks’) are taken every 20 minutes during continual periods of working in safety cabinets or on the bench top.

Computer Workstations

In some laboratory settings, standard office workstations are not permitted and therefore designated separate office space would be provided ideally. If computer workstations are based within a laboratory area, they should ideally be set up on standard desks and not on laboratory benches. If the latter is the only or most suitable option, it should be set up to mirror that of a standard office computer workstation. See (http://www.admin.ox.ac.uk/safety/s303a3.shtml) for guidance on minimum workstation requirements. The following are some basic guidelines for reducing risks of developing health problems whilst working at computer workstations.

Chair height should be adjusted so that arms are at right angles at the elbows, are held by the side and forearms and wrists are horizontal and flat over the keyboard.

Ensure there is space in front of the keyboard, i.e. between keyboard and edge of desk, to support hands/wrists during pauses in keying.

Ensure mouse is positioned close to the keyboard and user, in order to avoid stretching of the arm and awkward hand positions.

The chair seat pan should be height adjustable and the back rest should be both height and tilt adjustable. Ensure lumbar region of back, i.e. lower back, is supported, by sitting back in the chair and by adjusting the height of backrest.

Use a footrest if support needed, i.e. feet should be resting on floor and if not, supported by a footrest.

Screen should be positioned directly in front of user and eyes should be level with the top part of the screen and be able to view the screen comfortably.

Space under desk should be kept free of obstacles to allow for postural change and avoid twisting, bending and stretching of the body.

Ensure short frequent rest breaks (‘micro breaks’) are taken every 20 minutes during continual periods of working at a computer workstation.

It is important that users inform their management if they develop symptoms related to the use of laboratory equipment. If symptoms do not subside following adjustments to their equipment and/or practices, advice can be sought through the Occupational Health Service and users can then be referred if required.

Don’t ignore symptoms!