This is from a Peterson Institute working paper, by Peter Petri and Michael Plummer, that estimates the economic effects of the TPP:
The bottom half of the table shows NTBs, represented as tariffs that would have had the same protective effect (tariff equivalents). NTBs include quotas in agriculture and energy, standards and regulations that may be arbitrary, measures that explicitly or implicitly favor domestic producers, certification requirements that are unreasonably difficult to meet, lengthy or unpredictable customs procedures, and a host of other limitations on how companies are allowed to operate in foreign markets. NTBs have been widely recognized as the leading challenge to trade policy (UNCTAD 2010) and data suggest that their use has been rising (Evenett and Fritz 2015), perhaps to compensate for declining tariffs.
Some regulations that have legitimate, welfare-increasing objectives (for example, product safety standards) may be included in estimates of NTBs developed by other researchers, but they should not be counted as barriers. To account for the exclusion of these components, only three-quarters of NTBs are considered barriers subject to reduction in the TPP. Like tariffs, the remaining NTBs are relatively low for goods, except for food products, textiles, and apparel. They are higher in service industries, which involve more regulated and less easily defined products. In addition to excluding legitimate regulations, the current analysis assumes that only 50 percent of the remaining NTBs in services and 75 percent of those in goods are “actionable,” that is, subject to politically feasible reductions through trade policy.
Combining those assumptions, the actionable portion of initially estimated NTBs is calculated as 56.3 percent for goods and 37.5 percent for services. To simulate the effects of trade policy, these barriers are then reduced in proportion to scores (from 0 to 100) that represent the quality of the provisions of an agreement that address barriers in various goods and service sectors. The scoring methodology is explained in appendix A; it relies on textual analysis of trade agreements by the WTO and other experts. Th e scores for the TPP are based, in the first instance, on such a quantitative analysis of KORUS. Because similar analysis is not yet available for the TPP, KORUS scores were subjectively adjusted (typically slightly downward) to account for differences between the two agreements. These adjustments are reported in appendix B.
Even after looking at Table 1 and Appendix A, I can't follow what the authors are doing when measuring the fall in NTBs through the TPP. I don't doubt that some aspects of the TPP could, in theory, reduce some NTBs, including arbitrary standards and regulations. But I'm not sure how the authors are tying specific TPP provisions to a reduction in actual NTBs.
