Programme Areas
Capacity Building
Annual Reports
GHS Expert Roster
Comprehensibility Testing
Financial Support and Resource Mobilization


Comprehensibility Testing: An assessment tool for targeted GHS capacity building

GHS Comprehensibility Testing (CT) is a survey-based method for obtaining information on the understanding of GHS hazard communication elements among the public. "Comprehensibility" refers to the ability of an individual reading a label or safety data sheet to understand the information sufficiently to take the appropriate precautionary measures. CT is therefore a key tool for assessing the effectiveness of chemical hazard communication pictograms and/or key statements and provides important feedback for developing a chemical hazard communication system and targeted training.

The results of CT can help identify areas where capacity building interventions are needed in order to improve understanding of GHS-based hazard communication elements, thereby improving protection of human health and the environment. It has an important and valuable role at various stages in the process of developing and implementing a National GHS Implementation Strategy, including:

  • informing the development of the situation and gap analysis, sectoral implementation plans, and identification of the measures needed to ensure the information provided is effective in promoting safe chemical use;
  • understanding what awareness raising instruments are necessary; and
  • use as an awareness raising and training tool.







The materials found below are the key tools for conducting GHS CT. They were developed by UNITAR in the context of the UNITAR/ILO Global GHS Capacity Building Programme based on previous versions developed by the University of Cape Town and the ILO. The objective of this updated version (September 2010) of the testing is to provide focused results with minimal resources. CT has so far been conducted in Zambia, South Africa, Nigeria, Senegal, the Gambia, Indonesia, Philippines, Thailand, Cambodia, Laos, Vietnam, and Jamaica.

The following resources are available:

  • The GHS CT Manual: This manual provides a description of the testing procedure, including an overview of the questionnaire, its modules, objectives, and expected outcomes, as well as general issues related to conducting interviews and testing.
  • Questionnaire: This form describes the pre-interview text to be read, and gives instructions on how each question should be asked and how the information should be recorded. Space is also provided for interviewers to record respondent answers.
  • Sample Safety Data Sheets, labels and pictogram table: Sample SDS and labels (and a pictogram table) are provided to be used with the modules and are given to respondents to test their comprehension of hazard communication elements.
    • Labels and pictogram table
    • SDS 1
    • SDS 2

The following are sample CT results and reports from UNITAR/ILO GHS pilot projects (however, please note that they are based on a previous version of CT and may not reflect the more streamlined methodology of the most current resource materials):

  • Senegal
  • Indonesia
  • Nigeria