Heat Illness

You Will Learn: What is heat illness? Where and why does it happen? How do you treat it? How do you prevent it? What are the WISHA rules about heat illness?

What is Heat Illness? Heat illness can be:  Heat rash  Fainting  Heat cramps  Heat exhaustion  Heat stroke

Where Does Heat Illness Happen? Heat illness can affect anyone, anytime. It can happen in foundries, laundries, construction projects, landscaping, agriculture, bakeries.

Why Does Heat Illness Happen? When a human body cannot dispose of excess heat, it stores it. When the heat is stored, the body’s core temperature raises and the heart rate increases.

Why Does Heat Illness Happen? Four environmental factors affect a body’s core temperature:  Air temperature  Humidity level  Radiant heat (such as the sun or a furnace)  Air velocity

Why Does Heat Illness Happen? Five personal characteristics affect a body’s core temperature:  Age  Weight  Fitness  Medical condition  Acclimatization to heat

How Does Heat Illness Happen? The body reacts to high external temperature by circulating blood to the skin, the skin temperature raises, and heat flows out through the skin. However, if muscles are being used for labor, less blood flow is available to the skin to reduce the heat.

How Does Heat Illness Happen? Sweating reduces the internal body temperature. However, sweating only works to reduce body temperature if the humidity level is low enough to permit evaporation and if fluids and salts lost are replaced.

Types of Heat Illnesses There are five main classifications of heat illness:  Heat rash  Fainting  Heat cramps  Heat exhaustion  Heat stroke

Types and Treatments Heat rash – or prickly heat, can occur in hot and humid environments where sweat is not removed from the skin. Usually disappears when worker returns to cool environment.

Types and Treatments Fainting –Can be a problem for workers un-acclimatized to heat. Moving around, rather than standing still, can help. Lying down can help.

Types and Treatments Heat cramps –Happens when workers perform hard physical labor in a hot environment. Most common in the arms and legs. Cramping can occur after work has stopped. Worker needs to take water every 15 to 20 minutes. Drinking an electrolyte replacement (like Gatorade) may help.

Types and Treatments Heat exhaustion –The whole body, especially the circulatory system, is extremely stressed. Possible symptoms are:  Pale, flushed face and neck  Clammy skin  Heavy sweating  Fatigue  Shortness of breath  Headache, dizziness or fainting  Nausea and vomiting  Rapid heartbeat and breathing

Types and Treatments Heat exhaustion treatment: –Get medical help. –Don’t leave the person alone. –While waiting:  Remove worker to cool place to rest  Remove as much clothing as possible  Give water and electrolytes  Don’t allow person to get chilled

Types and Treatments Heat stroke –The most serious stage of heat illness. Symptoms are:  Dizziness and confusion  Red, hot, dry skin  Nausea and vomiting  Very little sweating  Rapid pulse  High body temperature, 105° F or higher  Convulsions, fainting

Types and Treatments Heat stroke treatment: –Victim will die unless treated properly, only 50% survival rate. Call 911 immediately. While awaiting medical help, get victim into cool area, fan vigorously, apply cool water to clothing or skin, apply ice packs under arms and to the groin area.

Heat Stroke Risks You have a higher risk of getting heat stroke if you are:  Not physically fit  Overweight  Have chronic illness like heart disease or diabetes  Drink alcohol or take drugs, either illegal or prescription

Heat Stroke Risks (Continued)  Dehydrated, from diarrhea, fever, or not drinking enough water  Wearing heavy or tight clothing  Wearing PPE, such as a full body suit or respirator  Not used to workingin the heat (not acclimatized)

Becoming Acclimatized It usually takes 4 to 7 days of regular exposure, but everyone is different. Acclimatization needs to happen for workers returning to work after:  A prolonged absence  Recent illness  Recently moving from cool to hot climate

Becoming Acclimatized Workers should limit exposure to the heat and gradually build up exposure. Workers should be monitored closely for signs and symptoms of heat illness. You lose acclimatization in a few weeks if you stop working in the heat.

WISHA Rule on Heat Stress Labor and Industries Heat Stress Rule (WAC ) Temperature, radiant heat, or temperature-humidity combinations This rule specifies that any worker subjected to temperature extremes, radiant heat, humidity or air velocity combinations that are likely to produce harmful responses, shall be protected by adequate controls, methods, procedures or protective clothing. Labor and Industries safety & health inspectors could apply this rule when investigating complaints of excessive heat at a worksite.

OSHA Guidance on Heat Stress The OSHA Technical Manual offers guidance on constructing a complete heat stress program.OSHA Technical Manual A complete program can include:  Measuring environmental conditions,  Calculating work/load assessments, and  Personal protective equipment.

OSHA Guidance (Continued) Additionally, an employer can consider:  Administrative, work practice and engineering controls,  Body cooling devices, such as ice vests, wetted clothing, water-cooled garments, and circulating air.

OSHA Guidance (Continued) The OSHA Technical Manual has three appendices that teaches you how to: 1.Ask the right questions to review the workplace. 2.Evaluate a heat related illness or accident. 3.Use a wet bulb globe temperature measuring system.

ACGIH Guidance on Heat Stress The American Conference of Governmental Industrial Hygienists (ACGIH) has aAmerican Conference of Governmental Industrial Hygienists (ACGIH) publication about Threshold Limit Values (TLV’s) and has a chapter on Heat Stress, where you can learn to measure your work environment, compare to TLV’s and see guidance on:  Work/rest regimes,  Clothing,  Work activities, and  Water and salt supplementation.

Measuring Environmental Conditions These are two examples of instruments that can measure the environment to most approximate deep body temperature and other responses to heat. The instruments give you a Wet Bulb Globe Temperature Index. (WBGT) Both the OSHA Manual and the ACGIH TLV Guidelines call for the use of the WBGT.

For Additional Help For additional assistance in evaluating your workplace for heat stress hazards, you can call one of our industrial hygiene consultants. This is a confidential, free service not connected to regulatory inspections. Click below for local L&I office locations: Click here Click here to get a two-page summary on heat stress

Thank you for taking the time to learn about safety and health and how to prevent future injuries and illnesses.