TURI developed the Pollution Prevention Options Assessment System (P2OASys) tool to help companies determine whether the toxics use reduction (TUR) options they are considering improve upon their existing process when looking at environmental, health and safety topics. By using P2OASys, unforeseen negative environmental, worker or public health impacts may be identified prior to adopting the proposed changes.
Potential hazards posed by current and alternative processes identified during the TUR planning process are compared using data endpoints for eight main categories that encompass chemical, physical, psychological and environmental hazards.
Using both quantitative and qualitative data input, the tool has be set up to rate each category based on endpoints that correlate with values, key phrases, Global Harmonizing System (GHS) classifications, and other government agencies designations.
Within each category, there are subcategories that can be populated. Each of these subcategories has several options. For subcategories that have multiple options, the most hazardous criterion is used to provide the subcategory score. In each of the eight categories, P2OASys calculates the average of the two most hazardous values for the various subcategories to give a numerical rating for that overall category. To obtain a category score, the user must therefore fill in data or information for all subcategories possible.
The tool does not require every criterion, subcategory or category to be assessed in order to create an assessment. However, the more data that can be entered into each of the subcategories, the better the overall profile of the process will be.
The final P2OASys product score is an average of each of the eight categories for which there are data. If there is no data entered for a category, P2OASys drops that category from the product score calculation.
The assessment tool allows the user to provide greater or lesser emphasis on any of the eight categories. In some situations, certain restrictions or a desired TUR focus might warrant providing one category more impact on the overall assessment. In cases like this a sliding scale can be adjusted to increase the weight assigned to a category from 1 to 10, thereby altering the product/process score from the initial score. This weighted score can be compared with the original score.
Scores will range from 2 to 10 with the lower score being more desirable. The best way to make an assessment of your current process is to compare it directly with the alternative process(es) being considered.
If your current product or process has a worse score (i.e., a higher overall P2OASys score) than the alternative, this is a good indication that further plans to investigate alternatives should be considered.
It is important to note that P2OASys doesn't include economical comparisons or performance criteria. These considerations are necessary for a thorough assessment of alternatives. For projects focused on surface cleaning, the TURI Cleaning Lab can assist with performance testing.
Assessments made using P2OASys can vary from one person to the next for the same process or chemical. This has a lot to do with the technical expertise of the assessor. But to help make the process easier to start an assessment, the TURI staff are populating the database with common solvents. P2OASys scores for these chemicals can be downloaded to an active P2OASys session.
When using P2OASys, the user can compare individual chemicals or mixtures of chemicals in products. When working with a product, the typical starting point is with that product's Safety Data Sheet (SDS). However, SDSs are not all created equally, and information provided on a SDS may not be comprehensive and, in some circumstances, may not represent the most current scientific knowledge. In this case, the user is encouraged to seek additional sources of information for the chemical constituents within the product. TURI has created an Environmental, Health and Safety Data Resources subject guide that acts as a portal to information on a variety of chemical hazards.