Heat Claims Are Still Comp Claims: Southeast Contractors Before the Next 103-Degree Day
A North Carolina court ruling on heat-stroke liability and OSHA's 2024 fatality data show why tort immunity does not protect your mod. A single catastrophic heat claim can drag three rating years of renewal premium.
Heat-related workers' comp claims are treated like any other injury claim for experience rating purposes. A catastrophic heat-stroke claim with hospitalization and permanent disability can carry reserves well into six figures and affect your EMR for three rating years. Tort immunity protections that shield employers from civil lawsuits do not apply to the experience modification calculation. NCCI data shows the average lost-time claim cost in construction exceeds $48,000 (NCCI, 2025), and heat.
The North Carolina Industrial Commission ruled in Moreno v. Southeast Construction Services that an employer's heat-stroke claim was compensable under workers' comp, rejecting the argument that the worker assumed the risk of outdoor labor in July (NC Industrial Commission, 2024). The ruling landed in a summer where OSHA documented 23 heat-related workplace fatalities across construction and agriculture (OSHA Heat Fatalities, 2024).
Both numbers matter to your mod. Here is why.
A heat-stroke hospitalization is not a general liability claim. It is a workers' comp claim. It goes on your loss run. It enters your experience modification calculation. And if the reserves are high enough, it sits on your worksheet for three rating years.
Tort immunity does not protect the mod. The legal shield that prevents a civil lawsuit from a heat injury has zero bearing on how NCCI calculates your experience rating. The claim hits your worksheet the same way a fall, a crush, or a laceration would. The difference is that heat claims with hospitalization and disability tend to carry larger reserves than the average construction injury.
The dollar scale of a catastrophic heat claim
NCCI's 2025 State of the Line data shows the average lost-time claim in construction runs roughly $48,000 (NCCI, May 2025). A heat-stroke claim with hospitalization, ICU stay, and permanent disability can blow past that quickly. In our reviews of Southeast contractor worksheets, heat claims with serious outcomes tend to carry initial reserves between $75,000 and $150,000. A claim at the high end of that range, sitting on a worksheet for a contractor with $8 million in payroll, can move the mod 8 to 12 points.
That is not a hypothetical. A contractor with a 0.95 mod that takes on a $120,000 heat claim can see the mod climb to 1.05 or higher at the next valuation. On $8 million in payroll at a blended rate of $4.50 per $100, that 10-point swing is roughly $36,000 in additional premium per year. For three years.
The split point determines how much of that claim hits the primary layer versus the excess layer. For most mid-sized contractors in NCCI states, the current split point is $19,200 (NCCI, 2024). Claims above that amount get discounted in the excess layer, but the primary portion hits the mod at full weight. A $120,000 claim still pushes hard.
What carriers and rating bureaus actually look for
OSHA's Safe & Sound Week materials emphasize written heat-illness prevention plans, supervisor training, and emergency response protocols (OSHA, August 2024). Carriers care about the same things, but for a different reason. They want to see that the employer has controls in place because it signals lower claim frequency and faster claim resolution.
The controls that matter to underwriters and rating bureaus are not complicated. A written heat plan with thresholds for modified work schedules. Supervisor authority to stop work when conditions hit dangerous levels. A buddy system so workers flag symptoms before they become emergencies. An emergency transport protocol that gets someone to the hospital fast. A modified-duty pathway that brings the worker back at reduced capacity instead of letting the claim run open. And quarterly loss-run reviews that catch reserve creep before it lands on your worksheet.
These are the same controls OSHA cited in its 2024 heat fatality documentation. The agency noted that in most of the 23 fatalities, employers lacked written heat plans and workers had no authority to stop work (OSHA Heat Fatalities, 2024).
The reserve problem is the hidden cost
The initial reserve is not the final cost. But it is the number that hits your mod. If a carrier sets a $120,000 reserve on a heat-stroke claim in July, that reserve sits on your worksheet until the claim closes or the valuation date passes. If the claim settles for $60,000, the difference comes back. But the mod was already calculated on the higher number.
This is where most contractors get hurt. They do not know the reserve was set too high. They do not know it inflated the mod. They find out at renewal when the premium quote is $30,000 higher than expected and the broker says the mod went up.
Quarterly loss-run reviews catch this. If the reserve on a July heat claim is still at $120,000 in October and the worker is back on modified duty, that reserve needs to come down. A mod audit checks whether the reserves on your worksheet match the carrier's current claim files.
What an audit would check
An audit checks whether heat claims on your worksheet carry reserves that reflect current claim status, not the initial estimate. It checks whether the claim is coded to the correct classification. It checks whether medical-only claims are getting the 70% ERA discount they should. And it checks whether closed claims are still sitting open on your loss runs, dragging the mod higher than the actual loss history supports.
If your next renewal lands after a summer heat claim, send us your NCCI worksheet before the valuation date. We will review it at no cost.