An important question…
How changes within a standard—whether a sentence, a word, a figure, or a table—is modified, removed, or added—are indicated and documented.
This matter is crucial because when a new edition of a standard is released, we need to be able to quickly and clearly identify whether the requirements from the previous version have been altered, updated, or expanded. It’s also important to know if any new points that could impact our work have been introduced.
In what follows, I will explore these issues and review the methods employed by several standards to track such changes. I would like to emphasize that these insights are based on my personal experience working with the standards I regularly use. Undoubtedly, there are other methods that I have not encountered or am unaware of.
I will begin with ASTM—a widely used standard embraced by engineers across numerous disciplines.
To detect any potential changes in this standard, it is essential to carefully examine the footnotes on the first page, often printed in small font. These notes provide background information on the history of the standard and outline any modifications made. As illustrated in the image below, they may also direct you to the final page of the document for further details.
In some cases, you may see the letters a, b, c, d at the top of the first page next to the ASTM standard number. These indicate the sequence of revisions and amendments made to that standard in the same year. For example, “19a” represents the second revision in 2019, “19b” the third revision in 2019, and so on. For standards that are reapproved without any changes during these revisions, the year of reapproval is shown in parentheses, such as (2012).
The epsilon symbol (ε) indicates editorial changes to the final version of the document. The first change is marked with the number 1 after the epsilon, and subsequent changes are numbered 2, and so forth.
It’s important to remember that not all of these notations may be used in a single ASTM standard number.
The image below shows examples of what has been described above.
Now, let’s turn to the American Petroleum Institute (API) standards. API standards include a preface that specifies the review and revision cycle:
Generally, API standards are reviewed and revised, reaffirmed, or withdrawn at least every five years. A one-time extension of up to two years may be added to this review cycle.
This standard indicates changes made in the text by using lines and strikethroughs (although vertically), as shown in the image below:
It is worth mentioning that not all API documents follow the above rule.
The ASME Boiler and Pressure Vessel Code (BPVC), which consists of 13 sections, includes a SUMMARY OF CHANGES section within the first few pages. This section lists the details of the changes made along with the corresponding page numbers. Then, assuming you have read these explanations, the standard’s text only indicates the year of the revision in parentheses (as a margin note) at the beginning of the paragraph where the change has occurred, as shown in the example below:
Parts A, B, and C of Section 2, due to their unique structure, only include a summary of changes.
Regarding other ASME standards, the general practice is similar to what I described earlier: a summary list of changes is provided, and the locations of these changes are marked within the text using margin notes.
Finally, we come to AWS D1.1
This passage is taken from the 2020 edition of the standard and is self-explanatory:
“Underlined text in clauses, subclauses, tables, figures, or forms indicates a change from the 2015 edition. A vertical line in the margin of a table or figure also indicates a change from the 2015 edition.”
It is important to note that only the D1.X series of this standard uses this approach to highlight changes. Other AWS documents do not employ underlining or vertical margin lines alongside tables and figures.
