1. GOST R 55724—2013. Nondestructive testing. Welded joints. Ultrasonic methods. Available at: http://docs.cntd.ru/document/1200107569 (accessed: October 8, 2018). (In Russ.).
2. GOST 32569—2013. Process steel pipelines. Requirements for design and operation at explosion and fire hazardous and chemically hazardous plants. Available at: http://docs.cntd.ru/document/1200111138 (accessed: October 8, 2018). (In Russ.).
3. RD 153-34.1-003—01. Welding, heat treatment and control of pipe systems of boilers and pipelines during installation and maintenance of power equipment. RTM-1s. Available at: http://docs.cntd.ru/document/1200026674 (accessed: October 8, 2018). (In Russ.).
4. PNAE G-7-032—91. Unified methods of control of basic materials (semi-finished products), welded joints and surfacing of equipment and pipelines of nuclear power plants. Ultrasonic control. Part IV. Control of welded joints of steels of the austenitic class. Available at: https://meganorm.ru/Index2/1/4293842/4293842254.htm (accessed: October 8, 2018). (In Russ.).
5. ISO 17640:2017. Non-destructive testing of welds. Ultrasonic testing. Techniques, testing levels, and assessment. Available at: https://ru.scribd.com/document/372358555/ISO-17640-2017-en (accessed: October 8, 2018).
6. DIN EN 1714—2002. Non-destructive testing of welds. Ultrasonic testing of welded joints. Available at: https://docslide.us/documents/din-en-1714092002-ultrasonic-testing-of-welded-joints.html (accessed: October 8, 2018).
7. ISO 11666:2010. Non-destructive testing of welds. Ultrasonic testing. Acceptance levels. Available at: http://www.studmed.ru/iso-11666-2010-non-destructive-testing-of-welds-ultrasonic-testing-acceptance-levels_d93c3ee64df.html (accessed: October 8, 2018).
8. DIN EN 1712—2002. Non-destructive testing of welds. Ultrasonic testing of welded joints. Acceptance levels. Available at: http://nd.gostinfo.ru/print.aspx?control=27&id=4041994&print=yes (accessed: October 8, 2018).
9. STO Gazprom 2-2.4-083—2006. Instructions for non-destructive methods of welded joints quality control at the construction and maintenance of field and main gas pipelines. Available at: https://standartgost.ru/id/1072446 (accessed: October 8, 2018). (In Russ.).
10. STO 00220256-005—2005. Seams of butt, fillet and T-shaped welded joints of vessels and apparatus operating under pressure. Ultrasonic Testing Methods. Available at: https://standartgost.ru/id/1069715 (accessed: October 8, 2018). (In Russ.).
11. RD 34.17.302—97 (OP 501 TsD—97). Steam and hot-water boilers. Steam and hot water pipelines, vessels. Welded connections. Quality control. Ultrasonic testing. Main provisions. Available at: http://files.stroyinf.ru/Data2/1/4294817/4294817159.htm (accessed: October 8, 2018). (In Russ.).
12. Recommendations on the design and safe operation of process pipelines: Safety Guide. Ser. 03. Iss. 67. Moscow: ZAO NTTs PB, 2018. 194 p. (In Russ.).
13. PB 03-585—03. Rules for design and safe operation of process pipelines. Ser. 03. Iss. 25. Moscow: ZAO NTTs PB, 2012. 152 p. (In Russ.).
14. PB 03-440—02. Rules for personnel certification in the field of non-destructive testing. Ser. 28. Iss. 3. Moscow: ZAO NTTs PB, 2018. 60 p. (In Russ.).
15. ISO 9712:2012. Non-destructive testing. Qualification and certification of NDT personnel. Available at: https://www.iso.org/ru/standard/57037.html (accessed: October 8, 2018).
16. EN 473:2000. Non-destructive testing. Qualification and certification of NDT personnel. General principles. Available at: https://shop.bsigroup.com/ProductDetail/?pid=000000000030147320 (accessed: October 8, 2018).