An accessory dwelling unit burns during an experiment at the Institute for Business & Home Safety center Wednesday, April 1, 2026, in Richburg, S.C. (AP Photo/Erik Verduzco)

Chester County Firefighters Elizabeth Stevenson, from left, Michael Mackey and Charles Lee, watch an accessory dwelling unit burn during an experiment at the Institute for Business & Home Safety center Wednesday, April 1, 2026, in Richburg, S.C. (AP Photo/Erik Verduzco)

A person walks near fans used for wildfire research at the Institute for Business & Home Safety center on Thursday, April 16, 2026, in Richburg, S.C. (AP Photo/Erik Verduzco)

Wildfire researchers watch an accessory dwelling unit burn during an experiment at the Institute for Business & Home Safety center on Thursday, April 16, 2026, in Richburg, S.C. (AP Photo/Erik Verduzco)

Wildfire researchers watch an accessory dwelling unit burn during an experiment at the Institute for Business & Home Safety center on Thursday, April 16, 2026, in Richburg, S.C. (AP Photo/Erik Verduzco)

Wildfire researchers and firefighters watch as an accessory dwelling unit burns during an experiment at the Institute for Business & Home Safety center on Thursday, April 16, 2026, in Richburg, S.C. (AP Photo/Erik Verduzco)

An accessory dwelling unit burns during an experiment at the Institute for Business & Home Safety center on Thursday, April 16, 2026, in Richburg, S.C. (AP Photo/Erik Verduzco)

The interior of an accessory dwelling unit sits at the Institute for Business & Home Safety center on Wednesday, April 1, 2026, in Richburg, S.C. (AP Photo/Erik Verduzco)