YORBA LINDA, Calif. — Wet rag in hand, the older woman was trying to clean her filthy, packed garage to comply with a warning that she was violating city codes. As two officials approached to check on her progress, she proudly pointed to an open box in which she had placed two dead rats.

For maximum display, she had perched the box atop one of the garage’s many dense, waist-high piles: bins overflowing with clothes and cans, a bicycle frame, a mildewed mop.

Darren Johnson, an inspector with the Orange County Fire Authority, and Mary Lewis, a city code enforcement officer, smiled encouragingly. They maneuvered into the woman’s townhouse, its passageways blocked by the detritus of a troubled life. Both are members of the Orange County Task Force on Hoarding, trained not to gag at the stench, even as their shoes squished on newspapers slippery with rat urine.

Mr. Johnson, who with Ms. Lewis accompanied a reporter into the woman’s home on the condition that she not be identified, shined a flashlight over tangled electrical cords and ancient magazines. If a fire broke out, he told the woman, “my guys would have a tough time getting inside.”