Ergonomic Aspects of Pipette Design & Use

Working with pipettes in laboratories demand a lot of concentration and precision. Pipettes are often used to carry out some chemical reactions, which involve chemical reagents. Risks are always associated while working with chemicals. A number of pouring and dropping of chemicals poses more threats to the safety of working people. Using pipettes for long hours is associated with an increased risk of hand and shoulder ailments. There are a number of factors, which should be considered for the safety of person while working with pipettes, such as the weight and length of the pipette, the force required to operate the pipette and how the pipette fits into the hand. Pipettes are available in a large range of makes and models in the market. Each of them have varying features in terms of ease of use, technical specification and price. The various features of the pipette will influence comfort and ease of use. Here we will be concentrating on the ergonomic aspects of pipette design and use.

Ergonomic Design
The application of ergonomics during the design and manufacturing of pipettes ensure safe, comfortable and efficient pipettes. The reliability and accuracy are essential for the repetitive usages of pipettes. The design of a product must take account of users, what tasks they perform, what type of equipment they use and about the environment in which they work. A pipette's design should allow a neutral position of the user’s wrist and hand. It should not require extra amount of force for operating the pipette and it should minimize any contact stresses incurred to the hand.

The following are some of the main ergonomic points to consider when selecting a pipette. A good pipette must have the following the characteristics. It should have good grip and comfortable to hold. It should be light in weight and shouldn't have any sharp edges or ridges. A pipette must have easy tip ejection and fitting. It should be suitable for right or left handed use. The plunger should be convenient requiring minimal force to push it.

Proper Working Posture

• While working with pipettes, it is quite important that there is minimum strain on muscles, ligaments, tendons, etc.


• Proper working height is important during pipetting while sitting or standing. The wrong height will put extra pressure onto the upper limbs. If the height is too low, the person will stoop and put strain on his back and neck. In case of excessive working height, the person’s shoulders and arms will be working in raised position and it will put tension on the muscles.


• There should be suitable chair for longer hours of pipetting. There should be enough leg space under the work surface to help the person sit closer to the work. The chair should be height-adjustable so that a good working posture is achieved. If the feet don't rest comfortably on the floor with the seat at proper height then footrests should be used.


• The wrist should be in a relaxed, not extended, flexed or rotated. The shape of the pipette hilt might affect the posture of the wrist.


• In a properly designed pipette, the thumb should not have to apply significant force. It may be under strain to depress the plunger.


• The various devices on the work surface should be positioned to allow a good working posture. The position and height of solution containers, sample holders and other equipment should minimize the need for twisting, bending or awkward stretching.

Hazards of Repetitive Pipetting
The people working in laboratories might repeat the task of pipetting again and again. According to researches the more repetitive the task of pipetting, the higher the chances of developing upper limb problems. To reduce the adverse effects of excessive pipetting include varying the work routine. You might introduce tasks that require varying postures and regular breaks. In fact, frequent breaks are more effective than working for longer hours and taking a longer break. It is suggested to change the work routine to alternate between a number of different tasks. Using an electronic pipette or a multi-pipette can also reduce the effects of repetition.

Optimally Designed Pipette
Pipettes shouldn't require excessive force while operating. In case if some extra amount of force  is needed than it means that the plunger is not easy to operate. So the thumb has to apply significant effort to press it. The higher viscous liquids might be the other reason for a forceful action. Pipettes designed with a shorter plunger are preferred because larger the distance the plunger has to be pushed, the more effort is required. The movement of pushing the plunger should be smooth. The effort to hold the pipette should be minimal. Some textured material or small ridges will reduce the effort required to grip the pipette. However the most effective way to decrease the amount of force to be applied is to use an electronic pipette. They require less effort in terms of operating, but their weight is more and may cause strain when holding for longer periods.

Choose the Proper Pipette
A number of pipettes are available in market with different make and models. You should choose the one which is easy to operate and provide safe and secure pipetting. These guidelines will help you while selecting a suitable pipette.

• The pipette  should be lightweight. Choose one that is cushioned or contoured to your hand.


• Choose the pipettes that use your fingers instead of thumb to operate a trigger.


• You should pick a plunger with low spring pressure and short length of travel.


• Choose a pipette of proper size. Wrap your hand around the pipette, if it covers less than half of the pipette, the pipette is too big. But if your hand wraps around the whole pipette, it is too small.


• The tip ejector should require little force. Thin-walled tips are easy for ejection. If possible use pipette-specific tips.