We are scientists making technology useful to our customers and reducing an accident to an incident

We are scientists making technology useful to our customers and reducing an accident to an incident

baseline-home / The portal of chemical risk / Occupational Medecine / Occupational Health Nurse (OHN) and chemicals

Occupational Health Nurse (OHN) and chemicals


Since the creation of the Inter University Diploma Course « DIUST » in 1994 in France followed by a license in occupational health, legislation as well as the OHN’s role keeps evolving. In addition the latest report drafted in May 2015 by (ISSINDOU-FANTONI) related to work ability and occupational health opens the doors even wider thus allowing the OHN to play her role fully as a prevention actor regarding health at work.

In this report the mission proposes the substitution of the pre-recruitment medical examination by a compulsory information-prevention check-up realized by the OHN under the occupational health physician’s responsibility. Following this visit, the OHN will be free to decide whether to refer the employee to the occupational health physician (OHP), if deemed necessary. The frequency of these OHN check-ups or subsequent medical examinations will be determined during and as part of this check-up, based on protocols and eventual exchange of views with the OHP. This visit must take place not later than three months following hiring of employees holding posts involving risks, and six months for others.

In other countries such as the United Kingdom, Finland, Nordic countries, the United States… the trained OHN is already in the capacity of fully playing her role in accompanying the worker towards the maintenance of his health and safety at work.

Having been responsible for the creation of these qualifying trainings, it is my wish, now that my new position enables me, to share with you my experience regarding chemicals which is a priori a field that creates fear, and one does not always have the necessary tools to increase awareness, knowledge and understanding of basic chemical mechanisms aimed at improving workers’ health and safety.

In this first dossier we will start by addressing hazard inventory.

Other dossiers such as work place risk assessment, prevention measures, whether collective or individual, management protocol for chemical accidents, as well as psychological aspects of victims will follow.


Hazard inventory must serve as a basis to the employer for the implementation of an appropriate prevention program. Thus, we must first start with a chemical hazard inventory, whatever our working environment. It is the hazard detection phase. We need to know and understand the nature of the hazard, identify chemicals used, first step often forgotten to address directly risks assessment, single document obliges! This approach will provide prevention stakeholders comprehensive information about chemicals used or stored in the company as well as mixed substances without forgetting cultural aspects, behavioral or habituation in the face of danger.


“Smell is not a potential hazard, but hazard has no smell”. The hazard of a product is related to the potential of its reaction. A hazardous chemical can be fatal in a few seconds. Hazard notion is intrinsic to the chemical molecule. Danger may arise from a variety of sources. It can be a substance as such, a mixture of substances, a co-exposure to several substances, storage incompatibilities, degradation of substances during use, intermediaries generated during technical process, waste. Danger also depends on the state of the matter, gas, liquid, solid, aerosol, dust etc.; of its physical properties, flash point, surface tension and ability to evaporate, pH upon dilution as well as its toxicological properties.


Hazard assessment requires knowledge in various fields: the nature of the chemical, official hazard classification, physical properties of the substance or mixtures well as toxicological properties. Hazard is officially classified into physical hazards (16 items), health hazards (10 items), and environmental hazards (2 items) and thus comprises 28 distinct hazard classes. As regards health hazard, it is classified as acute toxicity, skin corrosion /irritation, serious eye injury or irritations, respiratory or skin sensitization, mutagenicity on germ cells, carcinogenicity, and reproductive toxicity,target organ toxicity, single or repeated exposure and aspiration hazard.In practice it is appropriate to:

  • Know and understand the intrinsic chemical hazard nature.related to the molecular structure and detailed on data labels and SDS to compile a chemical hazards inventory at the workplace.
  • Collect data regarding exposure, that is: quantity, frequency, routes of entry, work unit, homogenous exposure group and individual exposure sheet. Implementation is also of importance: for example a heated product can release other components which may be hazardous.
  • Collect key technical data on chemical hazards in the company, hazardous situations as well as all exposures that may exist.
  • Identify chemical agents and monitor their hazardous properties, toxicological but also physico-chemical.
  • Maintain a current inventory of products used in the company, but also stored, emitted or in the process of being removed.
  • Analyze workplace situations independently within the framework of a structured delegation
  • Note and quantify information on hazards each represents
  • List and note all users of products
  • Prioritize information by hazard class, categories and level.

Data collection regarding hazards

Refers to Globally Harmonized System (GHS) regarding encoding elements which may be the trade name, chemical name, CAS number (universal identifier) and European, hazard pictograms’ list, the hazard class, the state of matter, degradation products, quantity (input/outputs,) as well as frequency of use etc. Of course a computerized system including common data entry applicable to several institutions or companies and automatic classification on each of the chosen criteria, the beginning and end of exposure will be useful.

Sharing experience within the multidisciplinary team, occupational physician and others: Upon completion of the first hazard identification phase, we shall adjust, complete then validate with the occupational health physician and collaborators this first working phase. This work accomplished by the OHN, will enable an exchange of personnel and professional experience. It will also allow if necessary, a second visit or in-depth studies of workstations and exposure circumstances, indispensable to the second phase which will be risk assessment in actual exposure condition. (see Dossier2) with the more precise characteristics section on pollutants, subsidiary tasks or exceptional, analysis of effective working time against prescribed work.


This first dossier helps us to understand that the well trained OHN; given his/her skills and know-how can effectively contribute and be involved in the different phases of data collection assessment and prioritization. The trained nurse can use her skills regarding project approach and can fully play her role as a coach and facilitator aimed at improving employees’ health and safety at work during the later phase of launching risk assessment in the company.

NB: You perhaps have questions, or wish to share your own experience. Please be assured that we will be very happy to include your comments on this page and look forward to your contribution so that the “OHN corner” becomes interactive, productive and informative for each other irrespective of, hazard data collection, data analysis and prioritization, your duties, or the country where you pursue your professional occupation.

Janine Bigaignon