Analysis of key factors affecting safety in coal seam mining in Quang Ninh region, Vietnam

The underground coal mining industry, particularly in the Quang Ninh region, holds a strategic role in national energy security. Protective coal pillar recovery is essential to maximize this resource, but this work takes place in the environment of an abandoned underground mine, facing substantial risks and challenges. The main purpose of this study is to systematically review, analyze, and conduct a qualitative and quantitative assessment of the natural and technical factors (such as geology, ventilation, and safety) that directly influence the protective coal pillar recovery process. The research is implemented through Literature and Theoretical Review to establish a theoretical foundation and classify the influencing factors, Analysis of Current Situation and Actual Conditions by collecting detailed primary data, Analysis and Assessment to quantify risks, group factors into Natural and Technical categories, and Verification and Adjustment of technical parameters through actual field testing. The assessment clarifies the specific influence of various factors, including the relationship between seam dip angle and the technological scheme, the increased risk of rock bursts in thick seams or with hard roof strata, and the significant safety threat posed by gas accumulation and the spontaneous combustion tendency of the coal. It has been confirmed that the workings are in a practically non-operational technical condition in high-pressure zones. Restoring a damaged working network is a serious challenge, increasing costs and risks. The study's findings allowed us to propose optimal technical measures to improve safety and enhance the economic efficiency of coal seam mining.

Hoang Hung Thang, Golik V. I. Analysis of key factors affecting safety in coal seam mining in Quang Ninh region, Vietnam. MIAB. Mining Inf. Anal. Bull. 2026;(3):152-169. DOI: 10.25018/0236_1493_2026_3_0_152.

Dr. Hoang Hung Thang, Rector of Quang Ninh University of Industry, Quang Ninh province, Vietnam, e-mail: hoanghungthang@qui.edu.vn, Scopus Author ID: 57225075880, ORCID ID: 0009-0003-4031-977X, 
V.I. Golik, Dr. Sci. (Eng.), Professor, Professor, Moscow Polytechnic University, 107023, Moscow, Russia, e-mail: v.i.golik@mail.ru, ORCID ID: 0000-0002-1181-8452.

V.I. Golik, e-mail: v.i.golik@mail.ru.

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