Audience note: This guide is written for chemistry teachers, school lab planners, college laboratory heads, distributors, importers, export buyers and government procurement teams.
Definition: A graduated pipette is a laboratory glassware item marked with multiple volume graduations so it can deliver different measured liquid volumes. A volumetric pipette is a laboratory glassware item calibrated to deliver one fixed volume, usually through a single mark on a bulb-type tube, and is chosen when accuracy for a specific aliquot matters more than flexibility. Lab Exports confirms pipettes in its Lab Glassware range, while exact pipette capacities, accuracy class, certificate type and material should be confirmed through an RFQ before publication or tender use.
What is a graduated pipette?
A graduated pipette is a measuring pipette with multiple graduation marks along its tube, allowing the user to deliver variable liquid volumes within its nominal range. ISO 835:2007 covers metrological and constructional requirements for graduated pipettes for general laboratory use. Under ISO 835, graduated pipettes are adjusted to deliver their specified volume under gravity, and the standard reference temperature is 20 deg C unless another national reference temperature is specified. Use a graduated pipette when flexibility is needed more than one fixed highest-accuracy volume.
What is a volumetric pipette?
A volumetric pipette, also called a single-volume or one-mark pipette, is calibrated to deliver one defined volume accurately. ISO 648:2008 covers volumetric pipettes with one mark and two marks for general laboratory purposes. The standard defines delivery volume as the liquid discharged from the pipette and notes that delivered volume is not identical with contained volume because liquid remains on the inner surface. Use a volumetric pipette for titration aliquots, standard-solution preparation and repeated transfer of one exact volume.
Core equipment and products for a school or college pipette setup.
| Priority | Item | Function | RFQ specification to confirm |
|---|---|---|---|
| Essential | Volumetric pipette | Delivers one fixed aliquot for titration or standard solution work. | Capacity in ml, Class A/AS/B, ISO 648 where applicable, TD/Ex, certificate need. |
| Essential | Graduated pipette | Delivers variable measured volumes in routine experiments. | Capacity in ml, subdivision in ml, Class A/AS/B, ISO 835 where applicable, type 1/2/3/4. |
| Essential | Pipette filler | Draws liquid safely without mouth pipetting. | Compatible bulb/filler type, chemical compatibility and student-safe operation. |
| Required | Pipette stand, vertical or horizontal | Stores pipettes upright or protected from rolling/breakage. | Lab Exports Laboratory Instruments lists vertical and horizontal pipette stands. |
| Required | Burette and conical flask set | Completes titration setup with pipette aliquot. | Burette volume, stopcock, flask capacity and certificate need. |
| Recommended | Spare pipettes | Covers breakage during classes and export transit. | Spare percentage, capacity mix and replacement lead time. |
Graduated pipette vs volumetric pipette comparison.
| Comparison point | Graduated pipette | Volumetric pipette |
|---|---|---|
| Main purpose | Variable-volume transfer from a graduated scale. | One fixed-volume delivery for an aliquot. |
| Typical selection logic | Choose when students need several volumes from one pipette. | Choose when one exact volume is repeated. |
| Accuracy expectation | Depends on class, capacity and graduation interval; generally less exact than one-mark volumetric for the same aliquot. | Normally higher accuracy for its stated volume; exact tolerance depends on class and capacity. |
| Standard to check | ISO 835:2007 for graduated pipettes, where specified. | ISO 648:2008 for single-volume pipettes, where specified. |
| Class options | Class A/AS higher grade; Class B lower grade under ISO 835. | Class and waiting-time marking to be confirmed under applicable ISO 648 version/datasheet. |
| Best school use | Classroom transfer, dilution practice and non-critical measurement. | Senior-secondary titration aliquot and standard-solution transfer. |
Specifications to check before buying pipettes.
| Specification | Unit / value to request | Why it matters | Source or status |
|---|---|---|---|
| Type | Graduated / volumetric / one-mark / two-mark | Controls function and accuracy expectation. | RFQ required. |
| Nominal capacity | ml, e.g. 1, 2, 5, 10, 20, 25 ml | Matches the practical experiment and batch size. | RFQ required. |
| Smallest graduation | ml, e.g. 0.01, 0.05, 0.1 ml where applicable | Controls readability and delivered-volume resolution. | ISO 835 table where applicable. |
| Accuracy class | Class A, AS or B | Controls permissible error and certificate expectation. | ISO 835 states A/AS higher grade and B lower grade for graduated pipettes. |
| Delivery basis | TD / Ex; gravity delivery; blow-out only if specified | Prevents students from using the pipette incorrectly. | ISO 835/648 context; verify marking. |
| Reference temperature | 20 deg C or 27 deg C if specified for national use | Volumetric glassware is calibrated at a reference temperature. | ISO 835 notes 20 deg C standard reference with 27 deg C alternative. |
| Material | Borosilicate / soda-lime / glass type | Affects chemical resistance and breakage/thermal risk. | RFQ-dependent unless product page confirms. |
| Certificate | Batch certificate / individual certificate / none | Needed for tenders and accuracy-critical procurement. | RFQ-dependent. |
Matching pipette type to education level and experiment.
| Level | Recommended pipette mix | Typical use | Procurement note |
|---|---|---|---|
| Class 6-8 | Mostly droppers or plastic transfer pipettes; limited glass pipettes under supervision. | Basic liquid transfer demonstrations. | Avoid fragile precision glassware for unsupervised use. |
| Class 9-10 | Graduated pipettes, fillers and stands. | Routine measurement and transfer practice. | Specify student-safe fillers and spare units. |
| Class 11-12 | Volumetric pipettes plus graduated pipettes. | Volumetric analysis, titration and standard solution work. | CBSE Chemistry practical includes volumetric analysis; confirm latest syllabus. |
| College | Class A/AS volumetric pipettes and graduated pipettes. | Quantitative analysis and repeated student batches. | Request certificate where marks, audits or method validation require it. |
| University / research | Certified Class A/AS volumetric sets and specialty pipettes. | Analytical and method-sensitive work. | Specify traceability and calibration documentation explicitly. |
Safety requirements for school pipette use.
| Hazard | Control measure | Procurement wording |
|---|---|---|
| Mouth pipetting | Never allow mouth pipetting; provide pipette fillers. | Quote pipette filler with every glass pipette set. |
| Glass breakage | Inspect chips, cracked tips and scratched graduations before issue. | Supplier to pack pipettes in protective sleeves/partitioned cartons. |
| Chemical exposure | Use compatible fillers and PPE for acids, bases and stains. | Quote safety spectacles and gloves where school policy requires. |
| Wrong delivery technique | Train students on meniscus reading, vertical holding and drain time. | Supply usage guide and marking explanation. |
| Unstable storage | Use vertical or horizontal pipette stands. | Include pipette stand; Lab Exports lists vertical and horizontal stands. |
| Contamination | Rinse correctly and segregate pipettes for standards/reagents. | Ask for labelled racks and storage plan for lab sets. |
Budget and RFQ notes without unsupported price claims.
| Cost driver | Why it changes price | How to ask in RFQ |
|---|---|---|
| Accuracy class | Class A/AS and certificates normally cost more than Class B. | Quote both routine grade and certified Class A/AS options separately. |
| Capacity mix | Small and large capacities have different manufacturing and packing needs. | List capacities and quantities line by line in ml. |
| Material | Borosilicate and specialty glass may change cost. | Specify material only where required; do not accept vague “glass”. |
| Certificate | Individual or batch certificate adds documentation cost. | State certificate requirement in the purchase order. |
| Packing | Export packing and sleeve protection increase packing cost. | Ask for breakage-safe carton details and carton count. |
| Freight/tax | GST, duty and freight vary by destination and shipment mode. | Request itemised GST, freight, duty and delivery terms. |
PIPETTE-12 pre-dispatch and acceptance checklist.
| # | Inspection point | Pass evidence required |
|---|---|---|
| 1 | Type confirmed as graduated or volumetric, not just “pipette”. | Purchase order line and supplier datasheet match. |
| 2 | Capacity checked in ml for every item. | Capacity printed on pipette and carton list. |
| 3 | Accuracy class confirmed where applicable. | Class A/AS/B marking or certificate. |
| 4 | Applicable standard checked. | ISO 835 for graduated or ISO 648 for volumetric where specified. |
| 5 | Graduations and single mark are legible. | Visual inspection under normal lab lighting. |
| 6 | No chipped tips, cracks, scratches or bent tips. | Random sample inspection and batch sign-off. |
| 7 | Pipette filler compatibility checked. | Filler fits suction tube and works without mouth pipetting. |
| 8 | Pipette stand/accessory included if ordered. | Accessory quantity tallies with BOQ. |
| 9 | Certificate/documentation enclosed if requested. | Batch or individual certificate attached. |
| 10 | Packing protects narrow tips during transit. | Sleeves, partitions, cushioning and fragile marking visible. |
| 11 | Labels and carton markings show capacity mix. | Carton label matches packing list. |
| 12 | Replacement/spare policy agreed. | Shortage/breakage reporting window stated. |
Vendor evaluation matrix for pipette suppliers.
| Criterion | What to verify | Weight |
|---|---|---|
| Specification compliance | Type, capacity, class, standard and certificate match RFQ. | 25% |
| Glassware quality | Legible marks, clean tip, no defects, consistent calibration marking. | 20% |
| Documentation | Datasheet, compliance sheet, certificate and packing list availability. | 15% |
| Accessory support | Pipette fillers, stands and replacement units available. | 15% |
| Packing and logistics | Protective sleeves, export cartons, fragile marking and damage process. | 10% |
| Institutional experience | School, college, tender or export supply experience. | 10% |
| Commercial terms | Price, GST/duty, freight, payment and lead time. | 5% |
Original proof asset: Pipette selection decision rule
Use this rule in BOQs and tender evaluations: choose a volumetric pipette when the experiment requires repeated delivery of one fixed aliquot; choose a graduated pipette when the experiment requires multiple measured volumes from one instrument; choose both when the lab teaches titration plus general liquid-transfer skills. If the purchase order simply says “pipette”, reject the line and ask for type, capacity, class, standard, certificate and compatible filler.
Decision rule matrix for pipette selection.
| Experiment need | Recommended item | Reason | RFQ warning |
|---|---|---|---|
| One fixed aliquot for titration | Volumetric pipette | Higher precision for one specified volume. | Do not substitute graduated unless teacher approves. |
| Several variable transfer volumes | Graduated pipette | Scale allows different delivered volumes. | Check smallest graduation and class. |
| Beginner transfer practice | Graduated pipette or plastic transfer pipette | Lower cost and flexible training. | Use filler; no mouth pipetting. |
| Accuracy-critical college analysis | Certified volumetric pipette | Certificate and class reduce uncertainty. | Ask for batch/individual certificate. |
| Export school kit | Mix of volumetric + graduated + fillers + stands | Covers both curriculum and safe storage. | Pack tips in protective sleeves. |
Common mistakes and pitfalls
Mistake 1: Writing “pipette” without type
A purchase order that says only “pipette” is incomplete. Specify graduated, volumetric, capacity in ml, class, standard and certificate need.
Mistake 2: Using a graduated pipette for a fixed high-accuracy aliquot
A volumetric pipette is normally the better choice when one exact volume is repeatedly needed for titration or standard solution transfer.
Mistake 3: Ignoring pipette fillers
Mouth pipetting should not be permitted in school or college laboratories. Include bulb fillers or mechanical pipette fillers in the BOQ.
Mistake 4: Forgetting pipette stands
Pipettes roll, chip and contaminate benches when stored loosely. Lab Exports lists vertical and horizontal pipette stands under Laboratory Instruments.
Mistake 5: Overbuying Class A items for every student activity
Class A or AS pipettes are appropriate for accuracy-critical work; Class B or routine grade may be enough for demonstrations. Match class to experiment risk and inspection requirement.
Mistake 6: Accepting unprotected packing
Narrow pipette tips break easily in transit. Require sleeves, partitions, cushioning and carton-level capacity labels for institutional or export supply.
Related guides and confirmed internal links
- Lab Glassware hub for beakers, flasks, pipettes, graduated cylinders, condensers and bottles
- Chemistry Lab Equipment category for school and college chemistry apparatus
- Laboratory Instruments category for pipette stands and accessories
- Cost Comparison of Imported vs Indian Chemistry Lab Glassware
- Class 12 Science Lab Experiments guide for practical-lab procurement context
- Lab Tender/OEM page for institutional and export enquiries
Frequently asked questions
Which pipette is best for school chemistry labs?
For most senior-secondary chemistry labs, the best choice is a mixed set: volumetric pipettes for fixed titration aliquots and graduated pipettes for routine variable-volume transfer. Class A or AS should be reserved for accuracy-critical work or where the tender asks for a certificate. Schools should also buy fillers and pipette stands so students do not mouth-pipette or store glassware loosely.
Do CBSE chemistry practicals require pipettes?
CBSE Chemistry 043 includes volumetric analysis in the Class XI-XII practical scheme, so pipettes are part of the practical glassware planning for titration work. The syllabus should be rechecked before tender publication because curricula can change. For procurement, match the glassware list to the actual experiment list rather than buying one generic kit.
Are graduated and volumetric pipettes safe for students?
Graduated and volumetric pipettes are safe for supervised student use when schools prohibit mouth pipetting, provide compatible fillers and inspect glass tips for cracks. Safety depends more on correct accessories and training than on the pipette type. Use eye protection where chemicals require it and store pipettes in racks or stands.
How much do graduated and volumetric pipettes cost?
The cost of graduated and volumetric pipettes is RFQ-dependent because price changes with capacity, class, certificate requirement, material, order quantity, packing and destination freight. Do not publish a price unless supported by a current supplier quotation or verified market benchmark. Ask for itemised GST, freight, certificate and export-packing charges in the quotation.
How do I maintain laboratory pipettes?
Maintain laboratory pipettes by rinsing immediately after use, avoiding abrasive cleaning, checking marks and tips before every session and storing them vertically or horizontally in a proper pipette stand. Segregate pipettes used for strong acids, alkalis or stains. Discard chipped or cracked pipettes because damaged tips affect delivery and safety.
What is the difference between a graduated pipette and a burette?
A graduated pipette transfers a measured quantity of liquid from a scale, while a burette dispenses liquid gradually through a stopcock during titration. A burette is read before and after delivery to calculate volume used, whereas a pipette is selected for transferring a known volume. Both are part of a full titration setup.
Key takeaways
1. Graduated pipettes deliver variable volumes from multiple scale marks, while volumetric pipettes deliver one fixed calibrated volume.
2. A volumetric pipette is normally the more accurate choice for one repeated aliquot, but exact tolerance depends on class, capacity and standard.
3. ISO 835:2007 covers graduated pipettes, and ISO 648:2008 covers single-volume pipettes used for general laboratory purposes.
4. ISO 835 identifies Classes A and AS as the higher grade and Class B as the lower grade for graduated pipettes; Class AS uses a specified 5 s waiting time.
5. Lab Exports confirms pipettes in its Lab Glassware range and lists vertical and horizontal pipette stands under Laboratory Instruments.
6. For bulk school, college or export supply, request a written BOQ through Lab Exports with type, capacity, class, standard, certificate, filler, stand, packing and freight clearly itemised.
About Lab Exports
Lab Exports, headquartered at Works: 11/315, Lalita Park, Laxmi Nagar, Delhi, 110092, supplies scientific and educational laboratory equipment for schools, colleges, universities, research centres and export buyers. The confirmed Lab Glassware page states that the range includes beakers, flasks, pipettes, graduated cylinders, condensers and glass bottles. The Contact page confirms the correspondence/works address, and the Lab Tender/OEM page should be used for bulk institutional enquiries. Certification, price, tolerance and current export documentation should be requested before tender use, not inferred from the website.
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