July is Extreme Heat Month: Know the Warning Signs of Heat-Related Illness on Mining Sites

A miner stands on equipment during a sunny day at a surface mine

Mining is a tough job, and many mine and mill workers are exposed to hot working conditions, especially during the summer months. Mining at hot work sites is challenging and can turn dangerous without the proper precautions. Workers nationwide face similar challenges at hot work sites. During Extreme Heat Month, we aim to provide information and resources to prevent heat-related illnesses at work sites.  

A “hot” work site is defined by several factors, including high air temperatures, high surface temperatures, high humidity and low air movement. Mine operators and owners need to ensure workers are properly trained and acclimatized so work sites remain safe.  

All workers – and supervisors in particular – need to recognize the conditions of a “hot” job and should be provided heat-stress training on worker risk, prevention, symptoms, monitoring, treatment and personal protective equipment. The objective should always be to keep workers’ body core temperatures from rising above 100 degrees Fahrenheit (38 degrees Celsius). 

These tips can help prevent dangerous – or even DEADLY– heat-related symptoms: 
  • Provide a work-rest regimen – acclimatization over an initial one- to two-week period, then frequent breaks and reasonably short work periods. 

  • Pace tasks to avoid exhaustion. 

  • Perform heavy tasks in cooler areas or at cooler times. 

  • Rotate personnel on hot jobs. 

  • Provide readily accessible cooler rest areas – 50 to 60 F (10 to 15 C). 

  • Provide cool drinking water 50 to 60 F (10 to 15 C) near workers at all times. 

  • Encourage or require all workers to drink a cup of water every 15 to 20 minutes.  

  •  Avoid drinks with caffeine, alcohol and large amounts of sugar. 

  • Drink lightly salted water (one level tablespoon of salt per 15 quarts of water for general use). See treatments for certain disorders for an alternate mix of salt and water. 

  • Caution against drinking extreme amounts of water; generally no more than 12 quarts over a 24-hour period. 

  • Provide sunblockers and proper protective clothing for individuals working in the sun. 

If a worker does show signs of heat stress:  


  • Remove the victim from the heat. 

  • Apply cool wet cloths.  

  • Fan the victim but STOP if goose bumps or shivers develop. 

  • Give water if victim is conscious. 

  • Seek medical attention if there’s no improvement.  


  • Give any stimulant, alcohol or cigarettes. 

  • Apply ice directly to the skin. 

  • Allow the victim to become so cold that shivering starts. 

  • Leave the victim alone. 

Help keep miners and all workers safe this summer by following these simple recommendations. Remember that owners, operators and supervisors are responsible for keeping workers safe and understanding how to prevent heat illness and injury.  

You can find additional resources here:

OSHA: Heat Illness Prevention 

MSHA: Heat Stress 

MSHA: Heat Stress - Health Hazard Card 


Stephen Gigliotti is the chief of safety for mine safety and health enforcement in the Mine Safety and Health Administration