Document unique: a risk prevention tool

The Single Document, which has been mandatory since 2001, identifies occupational hazards. Its collaborative and rigorous implementation is essential for prevention, safety and compliance.

Marie Faucon
EHS Consultant
Update : 
12.09.2025
Publication: 
02.05.2015

Compulsory since 2001, the creation of a Single Occupational Risk Assessment Document ( Document unique d'évaluation des risques professionnels) is still perceived by some companies as a complex and restrictive process. Beyond the need to comply with regulatory requirements, however, the Single Document represents a unique opportunity for each company to identify its priority risks and define a relevant, long-term prevention strategy.

Document Unique: what are the expected benefits?

The expected benefits are really significant, whether :

  • Reducing accidents and near-accidents,
  • Cost reduction,
  • Better employee health,
  • Controlling financial risks,
  • Reduced managerial risk,
  • Easier audit management

Review of best practices - methodological recommendations

We offer you a review of best practices and methodological recommendations to make the Single Document truly useful to companies.

1/ Gathering and using data already available

Before proceeding with the actual assessment of occupational risks, it is essential to identify and list the technical data already available in the company to identify and characterize the various types of risk present: employee exposure levels, protective measures implemented, job descriptions, accident scenarios, etc.

These input data can be found, for example, in measurement reports (e.g.: noise levels, concentrations of hazardous chemical agents at the workstation, etc.), operating instructions for machines and work equipment, incident or accident histories, CHSCT inspection reports, or chemical product safety data sheets (SDS).

It is advisable to collect and record all relevant data and values in the Single Document, so that they can be easily mobilized during the risk analysis phase.

2/ Involving employees beyond the EHS department

Drawing up the Single Document must be a collaborative process, involving not only the EHS department, but also representatives from all areas of the company. This approach makes it possible to :

  • on the one hand, to benefit from several different opinions and viewpoints when drawing up the hazard inventory and risk assessment
  • secondly, to encourage employee involvement and ownership of the approach.

In this way, the Document unique becomes the reflection of a genuine collective reflection carried out within the company.

3/ Relevant division of work units

The occupational risk assessment formalized in the Single Document must be carried out in each of the company's "work units".

A work unit can be defined as a group of employees exposed to similar risks. This notion may correspond to a workstation, or cover several work situations with the same characteristics. As a result, the division into work units may not be exclusively geographical, as some units may well cover different locations (e.g. material handling). To assess chemical or psychosocial risks, for example, it is also common practice to group employees into "homogeneous exposure groups" (GEH), or work units.

In all cases, the company must pay particular attention to the "granularity" of its division into work units. This can have a real influence on the results of the risk assessment, and on the amount of work to be carried out. However, the grouping of comparable exposure situations can only be envisaged once an exhaustive inventory of all work situations and their associated risks has been carried out.

4/ Ensuring the completeness of the risks taken into account

The company must not forget to take into account certain less obvious risks in its Single Document, such as :

  • risks related to thermal environments (high heat, cold)
  • risks with delayed effects (e.g. exposure to chemicals, night work or shift work)
  • emerging risks (e.g. optical radiation, electromagnetic fields, nanoparticles, etc.)
  • psychosocial risks, such as stress and harassment.

Such omissions are still frequent in company Single Documents.

In addition, the assessment must take into account the risks that may arise during all stages of an activity's operation:

  • start-up and shut-down phases
  • adjustment or maintenance phases
  • current operation
  • malfunctions
  • emergencies

In short, the medium used to formalize the Single Document should make it easy to distinguish and identify risks in normal, degraded or accidental operating modes. Finally, depending on the complexity of the company's activities, the contribution of an outside expert may prove useful in ensuring the completeness of the inventory of hazards and risks.

5/ Define an objective, consistent and transposable rating method

Once the risks have been inventoried and identified, the Document unique exercise consists in rating them according to criteria specific to the company (severity, frequency of exposure, occurrence, control....), in order to rank them in order of importance.

Risk rating must not depend on the sensitivity and subjective appreciation of the person in charge of assessing a risk. It must be based on factual elements. To this end, rating scales and criteria must be precise and documented, so that they can be understood and applied consistently by several people. This also ensures the consistency and reproducibility of analyses carried out in different work units. Imprecise rating scales ("little / a lot", "serious / not very serious", "often / sometimes") should therefore be avoided.

Logically, the rating criteria must also be adapted according to the type of risk. In concrete terms, an immediate risk of a fall or cut cannot be rated in the same way as a deferred risk linked to recurrent exposure to chemicals.

Finally, it is desirable that the rating method should lead to a sufficient dispersion of scores. This is to ensure that the hierarchy of risks is clear, and that priorities for action can be easily deduced.

Given the stakes involved, companies can opt for support in defining their rating method. This method can then be implemented in software. This will facilitate its application and prevent rating errors and inconsistencies.

6/ Regularly update the Single Document

Given that companies are constantly evolving, the assessment of occupational risks is a dynamic and evolving process. Accordingly, the French Labor Code stipulates that the Document unique must be updated in the following cases:

  • At least once a year => This periodic assessment should enable us to validate the effectiveness of our preventive actions, based on changes in ratings from one year to the next.
  • During any major transformation of a workstation resulting from equipment modification, product change or work organization.
  • When additional information concerning the assessment of a risk in a work unit is collected => This additional information may be of a scientific or technical nature (e.g.: new risk identified, new hazard classification of a chemical product, etc.), regulatory or drawn from accident feedback.

Aim for maximum added value, all the time

Beyond the mandatory nature of the risk assessment review, it should be noted that the added value of a good risk assessment can only be sustainable if it is regularly kept up to date. Your industrial site evolves regularly. Even if nothing changes, your view of safety does, if only for reasons of continuous improvement. However, without an appropriate solution, this regular updating becomes very "cumbersome" over time, especially for companies without an EHS manager on every site. Without a tool, your company would be depriving itself of the added value that genuine risk assessment management can bring: direct economic benefits, fewer accidents, better employee health, reduced risk to management in the event of an accident, improved social climate, easier audit management... creating value for the company.