0.1 sec Key Response (1472) Perceptual Processing (C) Instantaneous system response (M) Response to menu selection by key (ESD) 0.2 sec Key Print (1472) Max for displayed feedback in normal data entry (ESD) Pointing (from input to display) and Sketching (1472) 0.5 sec Min for simple data request, next page (ESD) Page Scan (1472) Local database update (1472) 1 sec Page Turn (1472) Immediate Response (C) Max for simple data request, next page (ESD) Max for no feedback (M) 2 sec Max for simple data entry (ESD) Min for error messages (278) Error feedback (1472) Response to selection of command (1472) Non-local database update (1472) 4 sec Max for error messages (ESD) 10 sec Max limit for keeping focus on task (M) Unit Task (C)