Abstract: At 10:00 a.m. on April 30, 2023, an employee working as a construction laborer on a residential project started work spraying foam insulation. The employee (the helper) and a coworker (the sprayer) had been working starting in the attic since the previous day and were working their way down. By the evening on April 30, 2023, the coworker was down on the ground floor and the employee was on the second floor scraping excess foam from between the studs, sweeping and cleaning up. According to the employer (co-owner) and sister-in-law of the employee, he spoke on the phone with his spouse for less than a minute around 6:05 to 6:06 p.m. outside of the structure. The coworker then noticed the foam was getting low and called out for the employee to change the barrel in the truck. After not hearing a response, the coworker turned around and found the employee unconscious near the front door and staircase. The coworker attempted to rouse the employee and when he could not, he called 911 and began chest compressions. The coworker called 911 at 6:10 p.m. and one minute later an ambulance arrived on scene and found the worker unconscious and pulseless. The employee had died of a heart attack caused by atherosclerotic and hypertensive cardiovascular disease. He had pre-existing medical conditions including obesity and hyperlipidemia. The narrative indicated a possible exacerbation due to exposure to MDI and lack of engineering controls.