A roofer in Naperville spends a July afternoon on a black shingle roof where the surface temperature runs far above the air temperature. A warehouse selector in Bolingbrook works a ten-hour shift in a building with no air conditioning. A road crew member on I-88 stands over fresh asphalt with the sun overhead. Each of them may start the day feeling fine and end it dizzy, nauseated, cramping, or unconscious.
Heat illness is frequently underreported as a workplace injury in Illinois, and injured workers often assume that collapsing from the heat is just an unfortunate fact of summer work rather than a compensable injury. That assumption can cost you significant benefits. If your job exposed you to heat to a greater degree than the general public faces, an injury caused by that heat may well be covered under the Illinois Workers’ Compensation Act.
Heat Illness Is a Medical Injury, Not Just Discomfort
Heat illness exists on a spectrum. Heat cramps and heat exhaustion — heavy sweating, weakness, nausea, headache, a racing pulse — are warnings. Heat stroke is a true medical emergency in which the body loses the ability to regulate its own temperature. It can cause kidney injury, neurological damage, cardiac arrhythmia, and death. Workers who survive a severe heat event sometimes have lasting problems, including reduced heat tolerance, cognitive difficulties, or a cardiac condition that did not exist before.
Because heat illness unfolds gradually, workers push through it, telling themselves they are dehydrated and will feel better after lunch. Supervisors sometimes reinforce this by discouraging breaks. The result is that a compensable injury goes unreported until it becomes a hospitalization.
When a Heat Injury “Arises Out Of” Your Employment
To recover benefits under the Act, an injured worker — referred to in Commission proceedings as the Petitioner — must show that the injury arose out of and in the course of employment. “In the course of” is usually straightforward: you were at work, on the clock, doing your job. The contested question in heat cases is almost always whether the injury “arose out of” the work.
Illinois law sorts workplace risks into categories. Risks distinctly connected to the job are compensable. Risks that are purely personal to the worker are not. In between sit what Illinois courts call neutral risks — hazards that are neither unique to the job nor personal to the employee. Ambient weather and temperature often fall into this middle category, because everyone is exposed to summer heat to some degree. An injury from a neutral risk is compensable only if the employment exposed the worker to that risk to a greater degree than the general public faces. That increased exposure can be quantitative, such as being outdoors in the heat far longer than an ordinary person, or qualitative, such as working next to a furnace or over hot asphalt.
The general public is not required to shingle a roof in direct sun for eight hours, load trucks in an unventilated trailer, work over hot asphalt, tend a foundry furnace, or wear heavy protective gear and a respirator in August. The comparison is not between you and another worker; it is between you and an ordinary member of the public going about an ordinary day. Where the work places you in hotter conditions, for longer, with heavier exertion, and with less ability to escape the heat, you may be able to meet the increased-risk standard. Compensability is never automatic, however: you must still prove the actual exposure, the medical diagnosis, and a causal connection between the two. Our post on what counts as a work-related injury explains this framework in more detail.
This is why the details matter enormously in heat cases. The temperature and humidity that day, the absence of shade or ventilation, the weight of what you were lifting, whether you were permitted to take breaks, and whether water was available are not background facts. They are the evidence that turns a neutral risk into a compensable one.
Heat, Exertion, and Cardiac Events
Some of the most significant Illinois heat cases are not labeled heat cases at all. They are heart cases, because heat combined with heavy exertion can trigger an arrhythmia, a heart attack, or sudden cardiac death.
In one decision of the Illinois Workers’ Compensation Commission, a City of Chicago sanitation worker was working behind a truck at Midway Airport when the temperature reached roughly 98 degrees. He became dizzy, and a supervisor told him he could not take a break. He kept working and became dizzy again, and he was taken by ambulance to the hospital. There he was diagnosed with heat exhaustion or heat stroke, and an EKG revealed atrial flutter. His treating physician opined that the combination of extreme heat and the intensity of his work precipitated the cardiac event. The Commission found a causal connection between the heat event and the atrial flutter and awarded benefits for the acute injury. Martin v. City of Chicago, 15 IWCC 148 (2015), No. 06 WC 52575.
In another Commission decision, a carpenter was stripping plywood forms from the underside of a bridge in July, kneeling in a confined space where the concrete radiated additional heat. He became ill, went into cardiac arrest, and later died. The employer’s medical expert argued that the worker was a heart attack waiting to happen given his coronary artery disease, high cholesterol, smoking history, and diabetes. The arbitrator was nevertheless persuaded by testimony describing how strenuous and hot the work was that day, and by the Petitioner’s expert, who explained that the warm temperature combined with intense physical exertion caused the plaque to rupture. Benefits were awarded, and the Commission affirmed. Madden v. Lorig Construction Co., 16 IWCC 33 (2016), No. 09 WC 38543.
These are Commission-level decisions, not published appellate opinions. They are examples of how each case turns heavily on its own facts. What they show is how the Commission actually weighs heat and exertion evidence, and that these claims are winnable when the record is built carefully.
A Pre-Existing Condition Does Not Automatically Disqualify You
Employers and insurance companies respond to heat-related cardiac claims with a predictable argument: the worker was overweight, had high blood pressure, smoked, or had known heart disease, so the collapse would have happened anyway.
Illinois law does not accept that reasoning as a general rule. Under Sisbro, Inc. v. Industrial Commission, 207 Ill. 2d 193 (2003), and Twice Over Clean, Inc. v. Industrial Commission, 214 Ill. 2d 403 (2005), an employer takes the employee as it finds him. A work injury is compensable if the employment was a causative factor in the resulting condition, even where a pre-existing condition made the worker more vulnerable. The heat and the exertion do not have to be the only cause, or even the primary cause. They must be a cause. We have written previously about how pre-existing conditions affect Illinois workers’ compensation claims.
There is an important qualification. The severity of a worker’s underlying disease, and evidence that an everyday activity could have triggered the same event, are factors the Commission weighs in deciding whether the work was in fact a cause of the injury. They are not a separate legal exception that defeats a claim after work-related causation has been proven. In practice, the outcome usually turns on which medical expert the Commission finds more credible, so developing strong, specific opinion testimony connecting that day’s conditions to the injury is critical.
Certain emergency personnel have an additional advantage. Section 6(f) of the Act creates a rebuttable presumption that heart or vascular and lung or respiratory conditions in qualifying firefighters, EMTs, and paramedics arise out of and are causally connected to the hazards of the employment. The presumption is not automatic. It generally requires at least five years of qualifying employment, does not apply to privately employed EMTs or paramedics who spend most of their time on nonemergency transfers, is limited to the heart, vascular, lung, and respiratory conditions the statute lists rather than every form of heat illness, and can be rebutted by the employer. If you work in one of these positions, an attorney can tell you whether the presumption applies to your claim.
What Benefits Are Available
If a heat-related injury is accepted or proven, Section 8(a) of the Act requires the employer to pay for medical treatment reasonably necessary to cure or relieve the effects of the injury, including emergency treatment, hospitalization, and follow-up cardiac or neurological care. Temporary total disability benefits under Section 8(b) pay two-thirds of your average weekly wage, subject to statutory minimums and maximums, while your doctor keeps you off work. If the injury leaves permanent impairment — a damaged heart, kidney injury, cognitive deficits, or heat intolerance that restricts the work you can do — permanent partial disability, wage differential, or in the most serious cases permanent total disability benefits may apply. Where a heat event is fatal, Section 7 provides death benefits to the surviving spouse and dependent children (and, where there is no beneficiary in a higher category, to other statutory dependents), along with a burial benefit currently set at $8,000.
What to Do If Heat Has Injured You at Work
Report the injury to your employer promptly. The Act generally requires notice within 45 days of the accident under Section 6(c), and an application for adjustment of claim must ordinarily be filed with the Commission within three years of the accident or two years from the last payment of compensation, whichever is later. Do not let a supervisor persuade you that heat illness is not a “real” injury and does not need to be reported.
Suspected heat stroke is a medical emergency: if someone has a very high temperature, confused or altered mental status, or loses consciousness, call 911 immediately rather than waiting. Otherwise, get medical attention the same day, and tell the treating provider exactly what you were doing, how hot it was, and how long you had been at it. Emergency room records that document the work conditions are among the most valuable evidence in these cases. Write down the temperature and humidity, whether shade, water, and air conditioning were available, whether you asked for a break and what the answer was, and the names of everyone who saw you become ill. Memories fade and coworkers move on; a contemporaneous record does not.
If your employer or its insurance company denies the claim on the theory that everyone was hot that day, or that your health history is to blame, understand that neither argument is automatically a winner. Illinois law addresses both. A denial is the beginning of the process, not the end of it.
Heat injury claims turn on evidence that is easy to lose and on medical opinions that must be developed with care. If you have been injured by heat exposure at work, or if you have lost a family member to a heat-related event on the job, the attorneys at The Law Offices of Millon & Peskin, Ltd. can evaluate your claim and explain your options. Learn more about how we represent injured workers in Illinois workers’ compensation cases. We serve injured workers throughout the Chicagoland area, including DuPage, Cook, Will, Kane, and Lake counties. Call 630-449-3884 for a free consultation.