Question 1

How do I choose the right safety factor?

Accepted Answer

Start with α = 0.5 for new lines or unreliable processes. Reduce to 0.1-0.2 as lead time variability decreases and process capability improves. For highly stable, mature processes (Cpk > 1.33), α = 0 is achievable. Never reduce α below the level where stockouts begin occurring.

Question 2

What container size should I use for kanban?

Accepted Answer

The container should hold roughly 5-10% of daily demand, enabling frequent replenishment. Too large a container increases lot sizes and delays signal detection; too small increases handling. Common practice: container quantity = 1-2 hours of demand at the consuming workstation.