Health and Safety

by Pete Fisher

Display screen equipment (DSE)

The use of Visual Display Units (VDUs) and other forms of Display Screen Equipment (DSE) is governed by the Health and Safety (Display Screen Equipment) Regulations 1992 (as amended in 2002). The regulations aim to prevent problems associated with the use of DSE, such as musculoskeletal problems, visual fatigue and stress. The likelihood of experiencing these is related mainly to the frequency, duration, intensity and pace of spells of continuous use of the DSE, in conjunction with other factors, such as the amount of discretion the person has over the extent and methods of display screen use and, importantly, the provision of the correct equipment.

Items classed as Display Screen Equipment include any alphanumeric or graphic display system, regardless of the display process involved, or (in more friendly language) a computer screen, CCTV screen, microfiche reader and so on.

A ‘Workstation’ is defined as comprising display screen equipment, keyboards, mouse, telephones, modem, printer, the office furniture and the immediate work environment around display screen equipment.

A ‘User’ means an employee who habitually uses DSE for a significant part of their normal work. It will generally be appropriate to classify members of staff as users if most or all of the following criteria apply:

  • They depend on the use of DSE to do their job
  • They have no discretion as to the use or non-use of the DSE
  • They need significant training and/or particular skills in the use of DSE to do their job
  • They normally use DSE for continuous spells of an hour or more at a time
  • They use DSE in this way more or less daily.

Possible effects

The introduction of DSE has been associated with a range of symptoms related to the visual system and working posture. These are often reflected in various types of bodily fatigue and mental stress, but are not unique to DSE work. You can reduce the risk to the user by applying simple ergonomic principles to the design, selection and installation of DSE, the design of the workplace and the organisation of the task, together with the provision of postural training and guidance.

Workstation assessment

It is particularly important that employers and managers consider the possibility of musculoskeletal disorders as a result of DSE use. Employers are required to conduct an assessment of each individual’s workstation and remedy any shortcomings that may be identified.

Equipment requirements

These shortcomings may be overcome through the provision of suitable office furniture, together with advice on workstation layout and work routine, or you may need to consider proactive health schemes (see Posture).


The choice of the screen and equipment should be considered in relation to the work being undertaken. The size of the screen is not defined in the regulations, but it should be large enough for the user to work comfortably.

Screens should be capable of being adjusted for angle, height, brightness and contrast and be free from glare or reflections.

Keyboard, mouse and other input devices

Again, the choice should be dictated by the task, but the design should allow quick, accurate input of information without discomfort.

If a user is experiencing any pain from the use of one particular style of keyboard or mouse, an alternative should be considered.

Work desk

The actual size of the work desk is not specified, but it must be large enough to allow the user to use the DSE plus any other items in use (telephone, paper, document holder, files and so on). The size must also allow the user sufficient space in front of the keyboard to support their wrists when not typing.

Work chair

Provision of a suitable, comfortable chair is arguably the most important factor for the DSE user. The chair must be fully adjustable for height, back adjustment and design to allow the user to achieve a comfortable working position (see Choosing a chair in the topic on Posture). Guidance must be made available to users on how to operate the adjusters on the chair: people frequently suffer discomfort simply because they do not know how to adjust their chair correctly.

Footrests may also be necessary if the user cannot rest their feet flat on the ground with the chair at the correct height for the desk.


The working environment is another key factor for user comfort and is governed by the Workplace (Health, Safety and Welfare) Regulations 1992. Factors such as lighting levels, space, heating and ventilation must be considered as part of the office planning and layout.

Work routine

The importance of taking regular breaks from DSE work cannot be over-emphasised. Work routines should allow staff to:

  • Incorporate micro-breaks into sessions at the computer
  • A break of five to ten minutes in the work pattern after approximately every hour of inputting data or text.

Taking a break from DSE work does not mean staff have to stop work every hour, on the hour. It means planning the DSE work so that there are frequent breaks from it in which they can do other work, such as making telephone calls and dealing with paperwork. In this way, they will be using different muscles and will not be static.


Layout of equipment

The layout of the workstation needs to be adapted to the individual and the items in use.

Eye tests

At the request of the user and where a user experiences visual difficulties which may be considered to be caused by work on DSE, employers are bound by the regulations to arrange an eyesight test. It may be necessary to repeat these tests at regular intervals.

The cost of the test(s) and any special corrective appliances (normally spectacles) must be borne by the employer. In the case of spectacles, however, the liability for costs is restricted to payment for the basic prescribed lenses and frames – in other words, not designer frames or lenses with optional treatments deemed unnecessary for the work.

Work with portable DSE (laptops)

An increasing number of employees are using laptops as part of their normal work, which makes the task of assessment more challenging to the employer. It is impracticable for the employer to analyse each location, therefore the user should be given sufficient training and information to make their own assessment and adjustments.

The use of portable equipment adds other risks, such as manual handling, theft and/or assault, which must also be considered by the employer.

Where laptops are used at a semi-permanent workstation, such as the main or home office, docking stations should be provided to allow the use of a full-size screen and keyboard.

Training and information

Users must be given suitable and understandable information, both on how to set up their workstation and on any software used. This is particularly relevant where bespoke or uncommon software forms part of the task.