CPIM Practice Exam

What is a time fence in production planning?

1. A deadline for submitting an order

2. A policy marking where restrictions on changes occur

3. An estimate of production costs

4. A method for tracking delivery times

The correct answer is: A policy marking where restrictions on changes occur

A time fence in production planning serves as a boundary that delineates different periods within the planning horizon for making changes to production schedules. The concept is critical for managing various aspects of the production process, such as controlling demand variability and maintaining a smooth operation. Time fences help organizations define when it's appropriate to make changes to open orders or scheduled production and when changes are limited or discouraged. The primary purpose of a time fence is to protect the production schedule from disruptions due to last-minute changes, thus facilitating stability and predictability in manufacturing operations. This is essential for effectively managing capacity, inventory, and lead times. In practice, organizations often use multiple time fences, typically categorized as "frozen," "slushy," and "liquid" zones. Each zone reflects different levels of flexibility and restrictions regarding changes to planned orders. In contrast, the other options do not pertain directly to the core concept of a time fence. A deadline for submitting an order concerns scheduling rather than the broader concept of managing changes. An estimate of production costs relates to financial planning but does not address timing restrictions. Finally, a method for tracking delivery times focuses on logistics rather than the management of production schedules and changes. These distinctions highlight the unique role that a time fence plays in effective