Many thanks for the opportunity to comment on this document. We appreciate that the management of NORM is challenging due to diversity of sources and pathways of exposure. Our general comments are given below.
We are aware that many regulatory authorities, including those in the UK, deal with a NORM industrial process as a planned situation which is a logical approach. We believe that this approach to regulating Industrial Processes using NORM is not properly addressed in the document. In lines 628 to 633 arguments are made as for the reasons for it not being a planned exposure situation. It states “In the vast majority of industries involving NORM, the application of ‘limits’ expressed in terms of dose provides no real additional protection for workers, and may entail administrative burdens that are not in keeping with efficient and effective use of resources.” Rather than argue against it being a planned situation it would be better if the document acknowledged that many countries take this approach but this may not be appropriate for all countries. The document could state that the intent, whatever approach is taken, is to provide an appropriate level of protection under the prevailing circumstances. Therefore we suggest that consideration should be given to removing or rewording lines 628 to 633 and also acknowledging in Section 4.1.2, Selection of the dose reference levels for workers, that some countries will regulate NORM in Industrial Processes as a planned situation and control exposures using dose limits.
The Scope states in para 12 that “the publication elaborates on management of existing exposure situations with regard to NORM”. This is a wider scope than suggested in the document title (Radiological Protection from Naturally Occurring Radioactive Material (NORM) in Industrial Processes). It is confusing for building materials and phosphate additions to animal feed to be included in this document as these are consumer product or end-products containing NORM rather than NORM in Industrial Processes. It is suggested that it would be better to deal with consumer or end-products in a different Publication or an Annex. Therefore, although recycling and reuse of NORM should be discussed within the document, Section 4.2.4 Building Materials, should be covered in another document or moved to an Annex.
Tables 2.1 and 2.2 do not give the primary references for their data and the activities in the Table are not listed in a consistent manner and give very variable levels of precision for dose. Table 2.2 also includes doses from construction materials which, in a previous comment, we suggest should be discussed in another document or Annex. We suggest that the tables should be either removed or all the data referenced and a greater consistency introduced into the tables.
Rather than having Tables 2.1 and 2.2 it would be helpful to the reader if the large variability in the activity concentrations and the impact on the potential exposures of workers was addressed in more detail in Section 2.1. Protecting workers from NORM containing low activity concentrations is very different from protecting workers dealing with technologically enhanced NORM (e.g. mineral scales and some metallurgical process residues) with concentrations of the order of up to several kBq/g.
Para 115 states that “A reference level of this order should also ensure that any radon exhalation from Ra-226 in building materials is unlikely to be the cause for the reference levels set for indoor radon concentration to be exceeded.” An activity Concentration Index of less than 1 is no guarantee that the radon exhalation is low as the exhalation rate is heavily dependent on the pore size and connectedness and/or friability of the building materials.
Comments complied from those received from Kelly Jones, Tracy Gooding and Ciaran McDonnell