3Mu: the corporate Swine flu

What on earth is 3Mu? Not a mathematical derivative of the Greek letter; nor yet the sound of three cats mewing together; but a virus that affects almost every manufacturing shop-floor. It is shocking but true, almost all manufacturing shop-floors are inflicted by the 3Mu virus. And like any virus, it can spread beyond the shop-floor to inflict the entire organisation or supply chain.

The term 3 Mu stands for muda, mura and muri - three Japanese words that roughly translate as waste (non-value adding), variation, and excess physical burden. Just like human health can be judged by the presence or absence of pathogens, similarly shop-floor health can be determined by presence or absence of the 3Mu virus.

Without going into the deeper ramifications, let us just examine the effect of 3Mu on the shop-floor. Though it is a common virus, like the common cold it is not easy to identify or kill, and it is a real challenge to find ways to keep it out forever.

Muda: the first Mu
This Japanese word means waste. Here we refer to waste in activities within processes, and not really waste in its physical form. That heap of material sitting as defective/scrap on the shop-floor is not really the muda; in this case it would be the wasteful activities involved in inspecting the production to find the defects or the rework that follows defect detection.

So 'rework' and 'inspection' are here the mudas (wasteful activities). These activities are performed by people; they cost money to perform, consumes resources, but add no value. Activity that costs money; but adds no value to the customer (internal or external) is muda - the first and worst kind of shop-floor virus! 

Symptoms