---
title: Learning Path: Design a Gas Sample System | Sarvesh
url: https://www.sarveshanalytics.com/learn/path-design-a-sample-system.html
description: A ten-lesson path on sampling: sample point, tubing, filters, cooling, pressure and flow, hot dusty gas, cryogenic samples, limits and troubleshooting.
updated: 2026-11-03
source: html
---

Learn · Learning path

# Design a sample system

Follow the sample from the tapping to the sensor and design each step on purpose.

 10 lessons About 33 min For: Instrument and process engineers designing or fixing a sample line

## What you will be able to do

- Choose a representative sample point
- Size tubing, flow and lag time
- Select filters, coolers and probes for the sample
- Keep condensate and dust out of the analyser
- Know which samples are out of scope

## Follow these lessons in order

1. [  **How to design a gas sample handling system** A good sample handling system delivers a representative, clean, dry sample at constant pressure and flow. The overview.  Intermediate*4 min*](https://www.sarveshanalytics.com/learn/how-to-design-a-gas-sample-handling-system.html)
2. [  **Choosing the sample point for a gas analyser** Take the sample where the gas is well mixed, at process conditions you understand, upstream of any air leak, away from dead zones, and with a tapping that cannot fill with liquid or dust. Where to tap.  Intermediate*4 min*](https://www.sarveshanalytics.com/learn/choosing-the-sample-point.html)
3. [  **Sample lines: materials, length, diameter and lag** Use stainless steel tube for trace oxygen, moisture and reactive gases, because plastic lets oxygen and water in and out. Tubing and time delay.  Intermediate*4 min*](https://www.sarveshanalytics.com/learn/sample-lines-materials-length-and-lag.html)
4. [  **Filters for gas analysers: dust, mist, membrane** Use filtration in stages: a coarse filter or probe filter near the tapping for bulk dust, a finer filter after the cooler, a coalescing filter to remove liquid mist and oil aerosol, and a membrane filter as a final guard. Dust and mist.  Intermediate*3 min*](https://www.sarveshanalytics.com/learn/filters-and-particulate-protection.html)
5. [  **Condensate, moisture and sample cooling for gas analysis** Wet samples must be cooled to a fixed, low dew point so that water leaves as condensate at a controlled place, not in the analyser. Water in the sample.  Intermediate*3 min*](https://www.sarveshanalytics.com/learn/condensate-moisture-and-sample-cooling.html)
6. [  **Sample pressure, flow and fast bypass loops** An analyser needs a steady sample at its specified pressure and flow. Pressure and flow.  Intermediate*3 min*](https://www.sarveshanalytics.com/learn/sample-pressure-flow-and-bypass-loops.html)
7. [  **Probes and blowback for hot, dusty and tarry gas** Hot, dusty or tarry gas needs a probe that survives the temperature, a filter at the tip that keeps dust out, and a way to clear the filter, usually automatic blowback with clean air or gas. Hard samples.  Intermediate*3 min*](https://www.sarveshanalytics.com/learn/hot-dusty-gas-probes-and-blowback.html)
8. [  **Sampling cryogenic and liquefied gases: vaporisers** A liquid sample must be vaporised completely before it reaches an analyser. Very cold samples.  Intermediate*3 min*](https://www.sarveshanalytics.com/learn/sampling-cryogenic-and-liquefied-gases.html)
9. [  **What samples an analyser cannot take: know the limits** Standard ACCURRA-S analysers expect a non-corrosive, non-toxic, non-flammable, non-condensing and dry sample, free of oil, at 2 to 10 psig and about 1 LPM, with dust below 3 micron. The limits.  Intermediate*3 min*](https://www.sarveshanalytics.com/learn/what-samples-an-analyser-cannot-take.html)
10. [  **Sample system troubleshooting: symptoms to causes** Most analyser faults are sample system faults. When it goes wrong.  Intermediate*3 min*](https://www.sarveshanalytics.com/learn/sample-system-troubleshooting.html)

Stuck on a real problem while you learn? [Ask an engineer](https://www.sarveshanalytics.com/contact.html#enquiry). Every lesson is checked against the figures in our catalogues.