Coolinno Phase Change Cooling Vest: Solving the Heat Hazard in Deep Mines, Providing a "Portable Air Conditioner" for Coal Miners

Target Industries: Coal mining, deep tunnel excavation, underground engineering
Application Scenarios: High-temperature operations such as underground mining faces, roadway maintenance, electromechanical transport
Product Solution: Coolinno mining-grade phase change cooling vest + dedicated cold storage box

As shallow coal resources in China are increasingly depleted, the depth of coal mining is extending deeper into the earth at a rate of 8–10 meters per year. At depths of 400 to 800 meters, due to the geothermal gradient, the original rock temperature commonly reaches 30°C–40°C or even higher. Coupled with the heat dissipation from mechanical equipment and the thermal radiation from electromechanical chambers, the ambient temperature at the working face often exceeds the upper limit stipulated by the Coal Mine Safety Regulations. This not only seriously threatens the physical and mental health of workers but also easily leads to fatigue, lack of concentration, and consequently, safety accidents.

Addressing this pain point, Coolinno conducted in-depth research into the actual working conditions of several deep mines in the Yunnan-Guizhou and Northern Shaanxi regions, and has launched the "Coolinno Mining-Grade Phase Change Cooling Vest + Dedicated Cold Storage Box" system solution. Utilizing advanced phase change material (PCM) technology and high-efficiency cold storage equipment, this solution provides a safe, efficient, and comfortable personal cooling solution for miners working long-term at depths of 400–800 meters.

Pain Point Analysis: The "Heat Stress" Challenge of Deep Mining

In mines exceeding 400 meters in depth, traditional central air conditioning or ice-making cooling systems often face issues such as long air supply distances, significant cooling loss, and high equipment deployment costs. When miners work at the excavation face, constrained by limited space and high physical exertion (heavy labor), their bodies face a severe "heat stress" challenge:

High Temperature and Humidity: The working face temperature in many mines remains above 30°C for extended periods, with humidity exceeding 80%, making it extremely difficult for the human body to dissipate heat.

Occupational Health Risks: Prolonged exposure to high temperatures can easily lead to increased heart rate, dehydration, heat cramps, and even heatstroke.

Increased Safety Hazards: Oppressive heat leads to slow operator response, while sweat causes slippery hands, increasing the risk of mechanical injuries.

Coolinno Solution: From "Local Ventilation" to "Personalized Precision Cooling"

In response to the above pain points, Coolinno has moved away from traditional bulky cooling vest designs. Adopting advanced composite phase change materials and ergonomic design, we have launched the Coolinno Cooling Vest and supporting dedicated cold storage box, specifically designed for heavy labor in coal mines.

1. Core Technology: High-Latent-Heat Phase Change Material
The cold storage packs built into the Coolinno Cooling Vest use n-octadecane and its composite materials as the base PCM. This material features high latent heat value (exceeding 300 J/g) and a precise phase change temperature (set to the human comfort zone of 26–28°C) . When the PCM changes from solid to liquid, it absorbs a large amount of heat, thereby creating a sustained microclimate cooling layer around the body.

2. Dedicated Cold Storage Box: Efficient Recharging Logistics Support
To solve the practical problems of batch cold storage and rapid recharging underground, Coolinno has simultaneously developed a matching dedicated cold storage box, establishing a complete cold chain support system from the surface to underground:

High-Capacity Batch Processing: A single cold storage box can centrally recharge 20–40 vest packs simultaneously, meeting the shift-change needs of an entire team and significantly improving operational efficiency.

Rapid Deep Freezing: Utilizing a high-efficiency compressor refrigeration system, the internal temperature can be stably controlled between -5°C and -10°C. Compared to ordinary freezers, the freezing time for PCM packs is reduced by approximately 30%, ensuring rapid recharging between shifts.

Mining-Grade Explosion-Proof Design: The cold storage box casing features an explosion-proof structural design, and electrical components comply with mining safety standards. It can be safely deployed at the mine entrance, underground rest chambers, or charging chambers, enabling "on-site recharging and replacement" without frequent trips to the surface.

Intelligent Temperature Control & Energy Optimization: Equipped with a digital temperature control system, it automatically adjusts compressor operation based on the stored cooling capacity, reducing energy consumption while ensuring freezing effectiveness, making it suitable for long-term continuous operation in mining areas.

3. Cooling Vest Product Design Highlights

Long-Lasting Duration: With deep freezing in the dedicated cold storage box, a single recharge provides effective cooling for 4–6 hours. Workers can replace with spare cold storage packs during shift changes or underground breaks, achieving seamless all-day coverage.

Explosion-Proof & Safety Design: The vest fabric uses flame-retardant, anti-static polyester-cotton blend, meeting underground safety production requirements. The PCM is RoHS certified – non-toxic, non-corrosive, and non-flammable. Even in the event of accidental leakage, it will not irritate the skin.

Ergonomic Optimization: Considering that miners need to perform large movements such as shoveling and carrying in narrow roadways, the vest features a form-fitting cut with cold storage packs distributed across the chest, back, and both sides of the waist. This layout minimizes obstruction to shoulder joint movement while covering the body's core heat dissipation areas.

4. Complete Usage Process

Surface Cold Recharging: Place the PCM packs into the Coolinno cold storage box located in the pithead rest room or lamp room. Set the temperature to -5°C to -10°C. Freezing for approximately 3–4 hours completes the deep recharging.

Underground Assembly: Insert the frozen packs into the vest's insulated pockets. Coolinno's special "cold insulation barrier" design prevents initial discomfort from excessive cold when first worn, ensuring a smooth transition to comfortable body temperature.

Underground Replacement (Optional): For work shifts exceeding the single-use duration, a smaller cold storage box can be deployed in underground rest chambers, allowing workers to quickly replace packs during meal breaks or shift changes – "replacing packs without going to the surface."

Continuous Operation: Wear the vest while entering the high-temperature working face. The PCM automatically absorbs body surface heat, continuously reducing perceived temperature by approximately 5–8°C.

Application Results: Real Feedback from Underground

Test Location: A deep mine under a mining group in Anhui Province (average operating depth: 750 meters)
Test Period: Summer 2025
Environmental Conditions: Coal mining face temperature 32°C, humidity 85%

Before introducing the Coolinno Cooling Vest and dedicated cold storage box, the mine relied mainly on ice blocks and high-power fans, but the airflow had already become "hot air" by the time it reached the end of the working face. Since equipping all staff with the Coolinno system in June 2025, significant results have been achieved:

1. Improved Physiological Indicators
Core Body Temperature Control: Wearable tests on 10 frontline miners showed that after 2 hours of continuous operation, the average armpit temperature of vest wearers was 0.8°C lower than non-wearers, with faster heart rate recovery.

Reduced Perspiration: Despite high ambient humidity, the localized microclimate improvement reduced overall perspiration by approximately 20%–30%, decreasing excessive electrolyte loss and lowering dehydration risk.

2. Enhanced Production Efficiency
Extended Effective Operating Time: Previously, workers at high-temperature faces needed to rest at ventilation points for 10 minutes after every 40 minutes of work. Wearing the Coolinno vest extended continuous operation to over 1.5 hours, effectively increasing equipment utilization and labor efficiency.

Optimized Logistics Efficiency: The introduction of the dedicated cold storage box increased recharging efficiency by 30%, eliminating the need to assign personnel for round trips to transport ice or replace cooling gear, saving labor costs.

Improved Worker Morale: As the mining team leader, Mr. Zhang, said: "Before, going down 800 meters felt like entering a fiery mountain – we'd sweat before even starting work. Now with this vest, our chests feel cool, and with the underground cold storage box for quick changes, we have more strength and peace of mind."

3. Enhanced Safety Management
Better Focus: The mine director reported that operational errors (accidental touches, misoperations) caused by high temperatures significantly decreased after introducing the personal cooling solution. The cool sensation helps workers maintain a clearer mind in noisy, dark environments.

In today's era of rapid intelligent and mechanized mining, caring for "people" is the cornerstone of sustainable corporate development. The perfect integration of the Coolinno Phase Change Cooling Vest and the dedicated cold storage box is not just a piece of clothing or a piece of equipment – it is a technological safeguard for the "right to life" of individuals in deep-mine heat hazard environments.

From 400-meter development roadways to 800-meter excavation frontiers, Coolinno is committed to using advanced PCM technology and supporting equipment to "compress" the coolness of an air-conditioned room into a small vest, delivering health and comfort to every warrior who mines light from the darkness.

Coolinno: Providing "Portable Coolness" for High-Temperature Workers.

Note: Specific cooling duration and effectiveness are influenced by ambient temperature, humidity, and physical labor intensity. Coolinno offers customized cooling solutions. Mining groups are welcome to call for consultation or request sample testing.