7
Aug
Class A vs Class B Measuring Cylinders: What’s the Difference and Which One Should You Use?
Quick Answer
Class A measuring cylinders offer higher accuracy and tighter tolerances than Class B cylinders, making them ideal for precise scientific work. Class B cylinders are more affordable and suitable for general-purpose lab use where exact volume measurements are less critical.
Why Understanding the Difference Matters
In any laboratory, accuracy in liquid measurement can directly affect the validity of an experiment or production process. Choosing between Class A and Class B measuring cylinders is more than a cost decision — it’s a matter of precision, compliance, and reliability.
Understanding which class suits your application ensures better reproducibility, fewer errors, and greater confidence in your data.
What Are Measuring Cylinder Classes?
Laboratory glassware is classified by measurement tolerance according to ISO and ASTM standards. The two most common classes for graduated cylinders are:
- Class A: High-precision glassware with narrow tolerances
- Class B: General-use glassware with broader tolerance limits
These classifications are marked on the cylinder and often colour-coded (Class A is typically blue or amber, Class B is clear).
Key Differences Between Class A and Class B Cylinders
| Feature | Class A Measuring Cylinder | Class B Measuring Cylinder |
|---|---|---|
| Tolerance | Tight (e.g., ±0.5 mL for 100 mL) | Looser (e.g., ±1.0 mL for 100 mL) |
| Calibration | Often individually calibrated | Bulk-calibrated (average range) |
| Certification | May come with traceable certificate | Typically uncertified |
| Ideal Use Cases | Analytical chemistry, QC labs | Education, general mixing |
| Price | Higher | Lower |
| Marking Visibility | Acid-etched, colour-coded (Class A often amber) | Clear or standard print |
Note: Tolerances vary by standard. Always check ISO 4788 or ASTM E1272 if compliance is required.
When to Use Class A Cylinders
Use Class A cylinders when:
- Accuracy is crucial (e.g., in quantitative analysis)
- Regulatory compliance is required (e.g., in pharmaceutical or food labs)
- You need traceable calibration
- The measured volume affects the outcome or quality of the final product
Common settings:
- Analytical chemistry labs
- Research & development facilities
- Pharmaceutical manufacturing
- Government testing labs
When Class B Is More Suitable
Class B cylinders are ideal for:
- Educational use (science classrooms, demonstrations)
- Approximate volume measurements
- Non-critical experiments
- General solution preparation where ±1–2% tolerance is acceptable
They’re also preferred for high-use environments due to their lower replacement cost.
Borosilicate vs Plastic Measuring Cylinders
Regardless of class, measuring cylinders are made from either borosilicate glass or polypropylene. Each has unique benefits.
| Feature | Borosilicate Glass | Polypropylene (PP) |
|---|---|---|
| Heat Resistance | Excellent – up to 180 °C or more | Moderate – up to 120 °C |
| Chemical Resistance | Very high | High (but may degrade with solvents) |
| Clarity | Crystal-clear, scratch-resistant | Slightly cloudy over time |
| Autoclavable | Yes | Yes (up to 121 °C) |
| Breakability | Fragile | Durable, unbreakable |
For high-heat or high-precision applications, glass is recommended. For rugged use or student environments, polypropylene is often preferred.
Why LabChoice Cylinders Stand Out
At LabChoice Australia, we stock a full range of Class A and Class B measuring cylinders made from BORO 3.3 borosilicate glass and high-grade PP plastic, available in sizes from 10 mL to 2000 mL.
- Class A cylinders come with colour-coded, acid-etched graduations
- Options include narrow or wide base, with or without stopper
- Cylinders are calibrated to ISO 4788 standards
- Glass options withstand flame, autoclave, and repeated use
- Fast delivery across Australia from our local warehouse
Shop Measuring Cylinders at LabChoice
Frequently Asked Questions
Do Class A cylinders come with calibration certificates?
Yes, many LabChoice Class A cylinders are available with traceable calibration certification upon request.
Can I use Class B cylinders for titration?
No. For titration, burettes or Class A volumetric equipment are preferred due to their accuracy. Class B cylinders are too imprecise for this purpose.
What sizes are most common in labs?
The most commonly used sizes are 50 mL, 100 mL, 250 mL, and 500 mL. LabChoice offers full kits or individual units across this range.
Author Details
LabChoice Editorial Team – Experts in Laboratory Measurement and Glassware Standards
We support Australian science educators, technicians, and industry professionals with reliable labware and trustworthy content.
Website: www.labchoiceaustralia.com.au
LinkedIn: LabChoice Australia
Twitter/X: @LabChoiceAU
