Dear professor Selan
I am really satisfied with your response but the articles from which you have taken the table do not have into consideration the limit of repetitivness given by ISO 11228-3 2007 that should be because their article is from 2005 and the standard was published 2 years after. This standard is completely based in OCRA method developed by professor Daniela Colombini Enrico Occhipinti from Clinica del Laboro Milano, the last one is also the chair of MSD technical Committee of the IEA.The OCRA stablish a limit of 30 technical action per minutes being really important to understand the concept of technical action which is more complex than a simple movement of a joint and similar to basic element in MTM UAS sytem but not exactly.
In my case I have had the honor to share with Enrico and Daniela during a visit to Cuba last February, they gave a course in OCRA check list.
Now since 3 month ago I am in Canada in Montreal at UQAM University for scientific interchange in order to support my PhD project. I am working with the Direction of Public Health of Montreal with ergonomist of this institution. A major concern regarding the MSD risk factor is the development of tool for a quick screening of work situation, this screening should be carried out by teams of practitioners in work Health of the Public health network. Usually with time constrain and not properly supported by the companies, often the detection of MSD risk should lead to the inclusion of this subject in a Program of Health Specific to the Company (PSSE in french)and if we consider that there is almost no situation in which MSD risk factor are not present so the problem is to determine when a significant ¨amount of Risk¨ is present to justified his inclusion in a PSSE. So tools like OCRA, Strain Index or even check list would not be suitable at this stage (the inclusion of MSD subject in a PSSE lead to a more detailed analyze of situation with this kind of tools).
If two o three ergonomist like you carry a visit to an enterprise such as the one that practitioner have to conduct I am pretty sure that at the end of the visit you will be able to identify the situation with the amount of risk justifying his inclusion in a PSSE, but what were de determinant of the work task that conduct you to say: this situation yes, this one not enough? Moreover without using any Video, Method of analyze or any other tool. I am trying to find this determinant; of course the experience and the level of knowledge in the subject are very influents aspects in the decision process.
In this moment I I am looking for TLVs that could help in some way to a rapid identification of a risk but TLV based in a scientific consensus like the limits proposed by ISO 11228 which at certain stage have been analyze by experts.
Finally another concern is the inter observer reliability in this quick decision process.