---
title: "Critical spare parts: how to spot them | attendo"
description: "What a critical spare part is, how to identify it by crossing lead time, criticality and usage, the metric that gives it away and why stock by value fails."
url: "https://attendo.me/en/glossary/critical-spare-part"
lang: "en"
---

# Critical spare part: the part that drags out downtime

Also known as: Critical spare

A critical spare part is one whose absence holds up the repair and drags out the equipment’s downtime. It is not the most expensive part or the most used one: it is the one you cannot get quickly.

## How to identify it

By crossing three pieces of data: the supplier’s **lead time**, the [criticality](https://attendo.me/en/glossary/asset-criticality) of the equipment it is fitted to and **how often it is used**.

For example, a $4 gasket with an eight-week lead time, fitted to the machine that stops the line, is a critical spare part. A $3,000 motor you can get in 24 hours is not.

## The metric that gives it away

Break down your [MTTR](https://attendo.me/en/glossary/mttr). If waiting for materials takes up more than half the time, you have a spare parts problem, not a technician problem.

## The usual mistake

Sizing stock by value instead of by risk. You end up with a storeroom full of cheap, fast-moving materials and without the part that really stops production.

## In attendo

Stock is tracked by warehouse, location and van, with minimum levels and alerts. Every part used is costed to the [asset](https://attendo.me/en/modules/assets) it was fitted to, and the [purchasing](https://attendo.me/en/modules/purchasing-and-stock) module works out the 90-day shortfall from the plans.

- [attendo CMMS](https://attendo.me/en/cmms)

## Where it is used in attendo

### Modules

- [Warehouse, purchasing and stock](https://attendo.me/en/modules/purchasing-and-stock): Warehouses, stock, purchasing and suppliers, without a spreadsheet
- [Assets and inventory](https://attendo.me/en/modules/assets): Each asset with its own record, QR code, history and readings
- [ERP integration](https://attendo.me/en/modules/erp-integrations): Odoo, SAP Business One, Business Central and Holded, connected
- [API v4, webhooks and MCP](https://attendo.me/en/modules/api-and-mcp): Connect whatever is not on the list, with permissions per key

### Industries that use these modules

- [Manufacturing and industrial plants](https://attendo.me/en/industries/manufacturing)
- [Energy and renewables](https://attendo.me/en/industries/energy-renewables)
- [Repair and after-sales service](https://attendo.me/en/industries/after-sales-repair)
- [IT services and MSPs](https://attendo.me/en/industries/it-services)
- [And any other business](https://attendo.me/en/industries)

## Related terms

Maintenance

### MTTR

Mean time to repair

MTTR (mean time to repair) is the average time it takes to bring equipment back into service after it fails. It measures responsiveness, not reliability.

Maintenance

### Asset criticality

Equipment criticality

Asset criticality is the impact that an asset’s failure has on service, production or safety. It helps you share out a maintenance budget that is always limited.

Maintenance

### Maintenance backlog

The maintenance backlog is the pending work that could not be done on time: open work orders, postponed preventive jobs and detected anomalies that are still unresolved.

[See all 53 glossary terms](https://attendo.me/en/glossary)

## Shall we look at it with your data?

We will show you how what you just read works in attendo, with your own assets, tickets and customers. If it is not a fit, we will tell you.

- With your operation, not a generic demo
- A real person from our team replies
- No cold calls afterwards

Would you rather talk first?

- Phone [+34 910 053 530](tel:+34910053530)
- Email [sales@attendo.me](mailto:sales@attendo.me)
- Monday to Thursday 9:30 AM to 6:30 PM and Friday 9:30 AM to 2:30 PM (Spain time)