The book “Open earth mining and preparation works . Counting the number of impurities (dust, methane) in the ventilation flow" is an indispensable source of knowledge for specialists working in the field of mining, mining construction and industrial safety. The author, remaining anonymous, has created a practical guide that reveals the most important aspects of the control and evaluation of harmful impurities in ventilation flows during excavation and mining operations in open pits and mines. This book will be a real discovery for engineers, technologists, geologists and occupational safety specialists seeking to improve the efficiency and safety of their projects. The book focuses on the determination and calculation of the amount of dust and methane in ventilation flows, which is critical for preventing emergencies and ensuring safe working conditions. The author analyzes in detail the methods of measurement and analysis of impurities, focusing on practical aspects that allow to quickly and accurately assess the level of air pollution .. The book presents modern technologies and equipment used for monitoring, as well as recommendations for their implementation in real mining conditions. A special place is occupied by the discussion of methods to reduce the concentration of dust and methane, which makes the book a valuable tool for those who are engaged in the design of ventilation systems and environmental safety control. The author not only shares theoretical knowledge, but also gives real cases based on experience in various mining enterprises, which makes the material as close as possible to practical activities. Thanks to this, the book becomes not only a training manual, but also a desktop guide for specialists facing similar tasks in everyday work. The book “Open earth mining and preparation works . The calculation of the amount of impurities (dust, methane) in the ventilation flow” is especially relevant for professionals involved in the preparation of quarries, the development of safe mining technologies and environmental monitoring. It is suitable for readers aged 25 years and older with basic knowledge in the field of mining or engineering sciences, as well as for students of specialized universities seeking to deepen their knowledge in the field of industrial safety and environmental monitoring. The author's style is distinguished by clarity, accuracy and practical orientation. There is no extra theory in the book - everything is presented in an accessible form, with an emphasis on real situations and solutions. This makes it particularly attractive for those who value practical experience and are looking for specific tools to improve the safety and efficiency of their work. The author is perhaps best known for his previous publications on mining engineering and industrial safety, which adds to the book's credibility and trust on the part of the professional community. If you are looking for a book that will help you understand how to correctly count and control harmful impurities in ventilation flows during excavation and preparation for mining, "Open earth mining and preparation work. Counting the amount of impurities (dust, methane) in the ventilation flow” will be an indispensable assistant for you. This book opens new horizons in the field of industrial safety, making your work safer and more efficient. It should be read not only by specialists, but also by everyone who is interested in modern technologies in the mining industry, ecology and labor protection.