Spare Parts Know How

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How do we determine spare parts criticality?

You are probably asking this because too many parts have been classified as critical, or because no one is confident that the current criticality ratings are accurate.

The reality is that not every important spare part is critical.

In fact, items that are critical for a machine to operate are not necessarily required as critical inventory.

This is counter-intuitive but also true.

And that distinction matters.

If everything is called critical, then the label stops being useful.

Criticality should help you make better decisions about stocking, review frequency, supplier management, maintenance support, and risk exposure.
 


The Common Mistake

 
The common mistake is allowing criticality to become an opinion.

In many organisations, parts are classified as critical because:

    the equipment is important,
    maintenance says the part is needed,
    the part has a long lead time,
    the part is expensive,
    the part has caused a problem before,
    no one wants to take the risk of saying it is not critical.

Each of these factors may be relevant, but none of them automatically makes the part critical.

A part is not critical simply because it is expensive.

Nor is it critical simply because it belongs to critical equipment.
 


What a Better Decision Requires

 
A better criticality decision separates consequence from emotion.

That means considering questions such as:

    What happens if the part fails and no spare is available?
    Does the failure stop production, reduce capacity, create a safety risk, or breach compliance?
    Is the item required to restore equipment function?
    Can the part be repaired, sourced quickly, substituted, or bypassed?
    Is the consequence based on current operating conditions?
    Is the classification consistent across similar parts and assets?

Criticality should be a decision input, not a label applied casually.

Used properly, it helps determine which parts deserve attention, which parts require stronger controls, and which parts may not need to be stocked at all.
 


Where This Is Covered

 
This topic is covered in the Foundation level, where you learn not only why criticality matters and why it is often misunderstood, but also a comprehensive, yet easy to apply framework for determining criticality.

For teams, Foundations for Teams helps create a shared language so criticality is not driven by the loudest voice in the room.
 


Choose Your Next Step

 
Explore Foundation
Understand the principles behind better spare parts stocking decisions.

Enquire about Foundations for Teams
Build a common decision language across the people who influence spare parts outcomes.
 

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Open Access

Open Access to 20 Years of Spare Parts Management Know-How. No email required. No data collection. Just pure know-how.
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Foundations Level

Our Foundation Level is designed to teach you the essential knowledge, tools, and techniques for effective spare parts inventory management.

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Operations Level

Perfect for those who need to go beyond the basics and revolutionize their company’s systems and approach.
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Practitioner Level

The Practitioner Level is designed for practitioners who need answers, not theory. It provides on-demand access to proven approaches, detailed explanations, and practical guidance across all areas of spare parts management.
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Foundations for Teams

A live, online, interactive, team-based delivery of our Foundations Level content designed to provide your team with a common understanding of the basics of spare parts inventory management. Read more...

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