One of the most common questions we receive is: "How do I choose the correct sampler?"
There is no single answer because every application is different. Poor sampling results are often caused by selecting the wrong tool for the material, process or environment.
The guide below highlights the key considerations that should be reviewed before selecting a sampler.
Why Am I Sampling?
Understanding the purpose of sampling is critical. The requirements for incoming goods inspection, quality control, retention samples or microbiological testing can be completely different.
- Particle size analysis requires representative sampling.
- Microbiological testing may require sterile sampling equipment.
- Quality control applications may need certified documentation.
- Retention samples may require specific storage conditions.
What Am I Sampling?
The characteristics of the material directly influence the type of sampler required.
- Powders: Free-flowing and cohesive powders require different sampling designs.
- Granules: Ensure sampling apertures are large enough for the particle size.
- Liquids: Viscosity affects sampler selection.
- Slurries & Pastes: Often require specialist equipment.
Where Am I Sampling?
- Available headroom above the container.
- Glove box or confined space restrictions.
- Accessibility of the sampling point.
- Cleaning facilities available after use.
- Manual or automated sampling requirements.
Sampler Material
Material compatibility is extremely important.
- Will the sampled product corrode the sampler?
- Will the sampler contaminate the sample?
- How long will the product remain in contact with the sampler?
- Are chemical resistance requirements understood?
Chemical resistance charts are a useful starting point but should always be reviewed alongside actual contact time and process conditions.
Reusable vs Disposable Samplers
Reusable Samplers
- One-time purchase cost.
- Suitable for repeated use.
- Typically stronger and more robust.
- Can be customised.
Disposable SteriWare® Samplers
- No cleaning costs.
- No cleaning validation requirements.
- Ready to use immediately.
- Eliminates cross-contamination risk.
Design & Ease of Cleaning
The design must match the application. Features such as tip geometry, tube diameter and construction quality can significantly affect performance.
- Fully welded construction.
- Easy disassembly.
- Electropolished surfaces.
- Validated cleanability.
Sample Removal & Surface Finish
Removing the sample efficiently is often overlooked. This is especially important when sampling expensive products or very small quantities.
Surface finish can also affect performance and cleanability.
- Satin Finish: < 1 Ra
- Mirror Finish: < 0.2 Ra
- Electropolishing further improves cleanability.
Documentation Requirements
Documentation requirements vary significantly between industries.
Reusable Samplers
- Certificates of Conformity
- Material Certification
- XRF Verification
- Surface Finish Certification
- Welder Certification
Disposable Samplers
- Sterilisation Certificates
- Batch Specific Documentation
- BSE/TSE Statements
- FDA & EU Compliance Documents
Electrostatic Considerations
If sampling flammable powders or liquids, electrostatic risks must be considered carefully.
- Use correctly earthed equipment.
- Consider ATEX-rated devices where necessary.
- Carry out a full risk assessment.
Good Sampling Practice
- Minimise sample handling.
- Reduce transfer steps.
- Use suitable containers or bags.
- Maintain sample integrity.
- Ensure appropriate storage conditions.
Risk Assessment
Every sampling operation should be supported by a suitable risk assessment.
- Adequate ventilation.
- Correct PPE.
- Sufficient lighting.
- Safe working space.
- Proper training.
Need Help Choosing a Sampler?
Our specialists are happy to help you select the correct solution for your application.