Fraud Alerts & Card Block/Replace — impact tolerance ≤ 1 hour — ITOL

Impact tolerance: ≤ 1 hour — any time; inability to block a card in real time is intolerable (illustrative default — trace the derivation, then replace with your own harm analysis)

Definition: Real-time fraud detection alerts to customers, and the ability for customers to block, replace, or re-issue cards.

Why it is designated: Customers face direct financial loss, and the statutory liability shift under Reg E, the federal electronic fund transfer rule, turns on timely notification. A fraud-block outage compounds losses linearly with duration. The money comes out of the customer's balance in the moment, then lands on the bank's P&L once the liability shift applies.