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Why Is Proper Chemical Labeling Important in Schools?

School laboratories often contain chemicals that are used only occasionally.

A bottle purchased for one semester's experiment may remain in a storage cabinet for several years. If the bottle is not clearly identified or its purchase date is unknown, staff may have difficulty determining whether the chemical should still be kept, inspected, or replaced.

A well-maintained chemical inventory can help a school keep track of:

• Chemical name
• Quantity
• Storage location
• Purchase or receiving date
• Opening date, when relevant
• Manufacturer information
• Expiration or retest information, when applicable
• Inventory or asset number
• Storage requirements
• Hazard information

The U.S. Environmental Protection Agency recommends that schools maintain a chemical inventory containing information such as the chemical name, storage location, purchase date, and amount of material. EPA also emphasizes that chemical management should support safe storage, purchasing decisions, use, and disposal planning.

Proper labeling therefore isn't just about making bottles look organized. It helps create a system that makes laboratory chemicals easier to identify and manage.

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What Information Should Be Included in a School Laboratory Chemical Inventory?

The exact labeling requirements depend on the chemical and applicable regulations. However, schools can establish a consistent internal inventory system.

For example, a chemical inventory record might include:

Information	Example
Chemical name	Sodium Hydroxide
Concentration	1.0 M
Manufacturer	Example Chemical Supplier
Product No.	ABC-123
Date received	October 6, 2026
Date opened	November 15, 2026
Expiration / retest date	See manufacturer information
Storage location	Chemistry Lab / Cabinet B
Hazard	Corrosive
Inventory ID	CHEM-0248
Quantity	500 mL

The manufacturer's original chemical label should remain intact and readable. OSHA guidance recommends maintaining labels on incoming chemical containers and ensuring that hazardous chemical containers have the chemical identity and appropriate hazard warnings.

A school can use additional labels or inventory records to track information such as the receiving date, opening date, storage location, or internal inventory ID without replacing the original safety information.

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Record the Purchase or Receiving Date

One of the simplest improvements a school can make is to record when a chemical enters the laboratory.

For example:

This gives laboratory staff a reference point when conducting periodic chemical inventories.

Older chemicals can then be identified more easily instead of remaining forgotten at the back of a cabinet.

EPA school chemical-management guidance recommends maintaining a chemical inventory and recording information such as the date of purchase and the location of chemicals.

A school may also record:

For chemicals that have a manufacturer-specified expiration or retest date, that information can be recorded separately:

This approach is more reliable than assuming that every laboratory chemical has the same shelf life.

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Don't Assume Every Chemical Has the Same Shelf Life

A common mistake is assuming that every laboratory chemical becomes unusable after a fixed number of years.

In reality, chemical stability can depend on:

• The chemical itself
• Concentration
• Container material
• Storage temperature
• Exposure to air or moisture
• Light exposure
• Whether the container has been opened
• Contamination
• Manufacturer specifications
• Storage conditions

For this reason, schools should not create a universal rule such as "discard every chemical after two years."

Instead, check the manufacturer's information and SDS, follow the school's chemical management procedures, and use receiving and opening dates to identify chemicals that may require review.

EPA guidance for schools also recommends identifying outdated chemicals and establishing procedures for managing chemicals that are no longer suitable for use.

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Example: Sodium Hydroxide

Sodium hydroxide (NaOH) is commonly used in chemistry teaching laboratories and is highly corrosive.

Solid sodium hydroxide can also absorb moisture and carbon dioxide from the air when exposed. This is one reason proper storage and container closure are important.

A school inventory label might record:

However, these dates do not automatically determine whether the chemical is safe or suitable for use. Laboratory staff should check the manufacturer's information, SDS, storage conditions, and institutional procedures before using an older chemical.

The purpose of recording dates is to make the chemical easier to review—not to create an arbitrary expiration period.

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Example: Hydrogen Peroxide

Hydrogen peroxide can gradually decompose, with its stability affected by factors such as concentration, contamination, light, and storage conditions.

Rather than applying a generic shelf-life rule, schools should record when the chemical was received and opened and follow the manufacturer's storage and expiration instructions.

For example:

If a chemical is old, damaged, leaking, contaminated, or otherwise questionable, it should be evaluated according to the school's chemical safety and disposal procedures.

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Pay Special Attention to Peroxide-Forming Chemicals

Some laboratory chemicals can form potentially hazardous peroxides during storage.

Examples include certain:

• Ethers
• Tetrahydrofuran (THF)
• 1,4-Dioxane

These chemicals deserve additional attention when maintaining a laboratory inventory.

OSHA's laboratory safety recommendations specifically advise that peroxide-forming chemicals be dated when received and dated again when opened. OSHA also recommends appropriate storage practices and keeping incompatible chemicals separated.

For example:

The exact inspection, storage, and disposal requirements should come from the chemical's SDS, manufacturer guidance, and the school's chemical hygiene procedures.

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Clearly Identify Corrosive Chemicals

Corrosive chemicals deserve especially clear identification because accidental contact can cause serious injury.

Common laboratory examples include:

• Sodium hydroxide (NaOH)
• Potassium hydroxide (KOH)
• Hydrochloric acid (HCl)
• Sulfuric acid (H₂SO₄)
• Nitric acid (HNO₃)

A laboratory should not rely on an unclear handwritten abbreviation when managing a shared chemical storage area.

For example, a storage-area label could clearly identify:

The original chemical container should continue to display the required chemical identity and hazard information.

The organizational label is there to make the storage system easier to navigate.

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Label Flammable Chemicals Clearly

Many school laboratories also contain flammable solvents.

Examples may include:

• Acetone
• Ethanol
• Methanol
• Isopropyl alcohol

A storage-area label could identify:

However, the label itself does not determine how a chemical should be stored.

Flammable materials should be stored using the appropriate equipment and procedures specified by the SDS and the school's chemical safety program. OSHA laboratory safety recommendations include appropriate storage cabinets and approved containers for flammable liquids.

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Don't Forget Oxidizers and Reactive Chemicals

Oxidizers require particular attention because they can increase the risk of fire or dangerous reactions when stored improperly.

Examples include certain forms of:

• Hydrogen peroxide
• Potassium permanganate
• Nitrates
• Other oxidizing reagents

A laboratory should not simply place all chemicals together in alphabetical order.

OSHA recommends consulting SDS information and keeping incompatible chemicals separated. It specifically recommends separating oxidizers, reducing agents, and fuels to reduce the risk of dangerous contact.

This means a well-organized laboratory should consider chemical compatibility and hazard category, not just alphabetical order.

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Label Chemical Storage Locations Too

Chemical organization is not only about labeling bottles.

Schools can also label:

• Chemical cabinets
• Shelves
• Storage boxes
• Laboratory refrigerators
• Flammable storage cabinets
• Acid cabinets
• Base cabinets
• Chemical waste areas

For example:

This can make it easier for authorized staff to return chemicals to the correct location.

It also makes inventory checks easier because the storage system itself has a consistent structure.

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Use a Chemical Inventory ID

For larger schools, universities, or districts, consider assigning each chemical an internal inventory ID.

For example:

The ID can correspond to a digital inventory record containing:

• Chemical name
• Manufacturer
• Product number
• Quantity
• Storage location
• Date received
• Date opened
• Expiration or retest date
• SDS location
• Responsible department

For larger inventories, barcodes can also connect a physical container or storage location with an electronic inventory record.

This can be especially useful when a school has multiple science classrooms or when several teachers share the same chemical storage area.

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Printed Labels vs. Handwritten Labels in School Laboratories

For a small classroom activity, handwriting may be appropriate for certain temporary labels when permitted by the laboratory's procedures.

For a school-wide organization system, however, printed labels can provide several advantages:

Handwritten Labels	Printed Labels
Different handwriting styles	Consistent appearance
Can be difficult to read	Easier to read
Information may be inconsistent	Standardized fields
Repeated information takes time	Templates can be reused
Limited space for structured information	More organized layouts
Harder to create inventory IDs	Easy to include IDs and codes

A label printer can be particularly useful when a school needs to create many consistent labels for:

• Chemical storage cabinets
• Laboratory equipment
• Shelves
• Storage boxes
• Drawers
• Workstations
• Cables
• Inventory IDs

The goal is not to replace safety documentation with a label printer. The goal is to make identification and organization information easier to read and maintain.

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Choosing Durable Labels for School Laboratories

Laboratories contain more than chemical bottles.

A typical school laboratory may also have microscopes, balances, centrifuges, computers, power supplies, incubators, network equipment, storage cabinets, drawers, shelves, and many cables.

For a complete overview of what to label in a lab—including equipment, samples, tubes, glassware, freezers, cables, and safety equipment—see our Laboratory Labeling Guide: What Should You Label in a Lab?

These items are frequently handled and may be exposed to water, cleaning products, abrasion, solvents, grease, or temperature changes. Ordinary paper labels may not always be the best choice for these applications.

For schools using DYMO Rhino label makers, durable Rhino-compatible vinyl and flexible nylon tapes can be useful for different laboratory organization tasks.

Permanent Vinyl Labels for Cabinets, Equipment, and Storage Areas

Colorty's compatible DYMO Rhino 18443, 18444, and 18445 permanent vinyl label tapes are available in 9mm (3/8"), 12mm (1/2"), and 19mm (3/4") widths. They are designed for durable identification on equipment, storage areas, and other demanding surfaces.

Different widths can work well for different laboratory applications.

9mm / 18443 Vinyl Labels

The 9mm format can be useful when space is limited, such as:

• Small equipment IDs
• Drawers
• Small storage boxes
• Shelf sections
• Instrument accessories
• Small organizational labels

For example:

12mm / 18444 Vinyl Labels

The 12mm format is a versatile choice for general laboratory organization.

It can be used for:

• Chemical storage cabinets
• Laboratory equipment
• Shelves
• Workstations
• Cabinet sections
• Storage areas
• Equipment identification

For example:

19mm / 18445 Vinyl Labels

The wider 19mm format can make larger labels easier to read from a distance.

It can be useful for:

• Large laboratory equipment
• Cabinet doors
• Storage areas
• Laboratory zones
• Larger organization labels
• Equipment identification

For example:

Colorty's Rhino-compatible vinyl labels are designed for applications requiring durable identification and are resistant to water, abrasion, corrosion, solvents, grease, and heat. They use thermal-transfer printing for clear, durable text.

Shop Colorty Rhino-Compatible Vinyl Labels →

Flexible Nylon Labels for Laboratory Cables and Wires

Laboratories often contain more cables and wires than students notice.

Microscopes, balances, computers, analytical instruments, incubators, printers, and other laboratory devices may have multiple cables running behind benches and equipment.

Trying to identify these cables with rigid labels can be inconvenient.

Colorty's DYMO Rhino 18488 and 18489 compatible flexible nylon labels are designed for flexible surfaces and can be used for wire and cable identification. They are available in 12mm and 19mm widths.

18488 / 12mm

Useful for:

• USB cables
• Power cables
• Network cables
• Instrument cables
• Smaller wires

For example:

18489 / 19mm

The wider format can be useful when more information needs to be printed or when labeling larger cables and equipment connections.

Shop Colorty Rhino-Compatible Nylon Labels →

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Use Labels to Organize the Laboratory, Not Replace Safety Labels

An important distinction should be made between organizational labels and required chemical hazard labels.

A school should never cover, remove, or replace a manufacturer's chemical label with a simple organizational label.

Chemical containers should retain the required identity and hazard information, and schools should follow applicable safety regulations, SDS instructions, and their own Chemical Hygiene Plan. OSHA specifically recommends maintaining existing labels on incoming chemical containers and ensuring appropriate hazard warnings are present.

Instead, durable printed labels can complement the existing safety system.

For example:

This creates a consistent visual organization system without replacing required chemical labeling.

While chemical containers require careful labeling, many other laboratory items also benefit from clear identification. Our guide on what to label in a laboratory covers equipment, samples, storage areas, cables, and more.

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Build a Consistent Labeling System Across the School

The biggest benefit of using a label printer in a school laboratory is not simply making individual labels.

It is creating a consistent labeling system.

For example:

Chemistry Lab

• Cabinet A — Acids
• Cabinet B — Bases
• Cabinet C — Flammables
• Shelf 1 — General Reagents
• Shelf 2 — Oxidizers

Equipment

• Balance 01
• Microscope 02
• Centrifuge 01
• Spectrophotometer 01

Cables

• BALANCE-01-USB
• PC-02-NETWORK
• INCUBATOR-01-POWER

This approach mirrors the broader laboratory labeling categories covered in our Laboratory Labeling Guide, which includes equipment, samples, tubes, glassware, freezers, and safety equipment.

Once a school establishes a naming convention, the same format can be reproduced whenever new equipment or storage areas are added.

This is where an industrial label maker and durable label tape can become useful. Instead of creating one-off handwritten labels, schools can maintain a consistent visual system throughout the laboratory.

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Which Rhino Label Should a School Choose?

Laboratory Task	Recommended Rhino Tape
Small equipment or storage IDs	18443 / 9mm Permanent Vinyl
General laboratory organization	18444 / 12mm Permanent Vinyl
Cabinets and larger equipment	18445 / 19mm Permanent Vinyl
Small cables and wires	18488 / 12mm Flexible Nylon
Larger cables or more text	18489 / 19mm Flexible Nylon

The best choice depends on the label maker, surface, available space, and information that needs to be displayed.

Always verify the tape and label-maker compatibility before ordering. Colorty's Rhino-compatible tapes are replacement products rather than original DYMO products. The current Colorty Rhino collection includes 18443, 18444, 18445 permanent vinyl and 18488, 18489 flexible nylon options for compatible Rhino label makers.

Explore the Colorty Rhino Label Collection →

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Create a Laboratory Labeling Checklist

Before putting a chemical into long-term storage, laboratory staff can review:

For a more comprehensive checklist that covers equipment, samples, chemicals, storage, and cables, see our complete laboratory labeling guide.

A consistent checklist can make annual or periodic laboratory inventory reviews easier and help schools identify chemicals that require further evaluation.

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Final Thoughts

Good laboratory organization starts with knowing exactly what is in the laboratory.

For schools and educational institutions, a useful chemical management and labeling system should make it easier to answer three questions:

For certain chemicals, additional questions may also be important:

Labels alone cannot make a laboratory safe. Chemical compatibility, storage conditions, SDS information, training, personal protective equipment, and proper disposal procedures are all essential parts of laboratory safety.

But clear and consistent labels can make those systems easier to manage.

By recording receiving and opening dates, maintaining an accurate chemical inventory, identifying storage locations, organizing equipment and cables, and using durable printed labels where appropriate, schools can create laboratories that are easier to manage and easier for authorized personnel to navigate.

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Frequently Asked Questions

What information should be included on a school laboratory chemical label?

The chemical should remain clearly identified and the appropriate hazard information should be available. For school inventory purposes, additional information such as receiving date, opening date, expiration or retest date, concentration, inventory ID, and storage location can also be useful.

Should schools record the purchase date of laboratory chemicals?

Yes. Recording the date a chemical is received or purchased can help schools maintain an accurate inventory, identify older chemicals, and make better purchasing decisions. EPA school chemical-management guidance recommends recording purchase dates as part of a chemical inventory.

Does an old chemical automatically become unsafe?

No. There is no universal shelf-life rule for all laboratory chemicals. Stability depends on the chemical, concentration, container, storage conditions, manufacturer specifications, and whether the container has been opened.

Schools should follow the manufacturer's label and SDS and use their own chemical management procedures when evaluating older chemicals.

Which chemicals need extra attention when tracking dates?

Some peroxide-forming chemicals, including certain ethers, tetrahydrofuran (THF), and 1,4-dioxane, require particular attention to receiving and opening dates. OSHA specifically recommends dating peroxide formers when received and again when opened.

Other chemicals may also have manufacturer-specified expiration or retest dates.

Should chemicals be organized alphabetically?

Not necessarily.

Chemical storage should consider hazard categories and compatibility rather than relying only on alphabetical order. OSHA recommends consulting SDS information and keeping incompatible chemicals separated, including separating oxidizers, reducing agents, and fuels.

Can a label printer be used for laboratory organization?

Yes. A label printer can be useful for creating consistent labels for equipment, cabinets, shelves, storage boxes, drawers, cables, inventory IDs, and other organizational applications.

For chemical containers, however, organizational labels should not replace required manufacturer or hazard labeling.

Which DYMO Rhino labels are useful for school laboratories?

Different Rhino-compatible tapes can serve different purposes.

18443 / 9mm Permanent Vinyl is useful for smaller equipment and storage labels.

18444 / 12mm Permanent Vinyl is a versatile choice for general laboratory organization, cabinets, shelves, and equipment.

18445 / 19mm Permanent Vinyl is useful when larger, more visible labels are needed.

18488 / 12mm Flexible Nylon and 18489 / 19mm Flexible Nylon are useful for cable and wire identification and other curved surfaces.

Can Rhino labels be used directly on chemical bottles?

The answer depends on the specific application, surface, chemical exposure, and the school's labeling procedures.

For hazardous chemical containers, do not cover or replace the manufacturer's required chemical and hazard label. Rhino-compatible labels are particularly useful for storage cabinets, shelves, equipment, drawers, laboratory areas, and cables, where durable identification can improve organization.

What should a school do with an old or unidentified chemical?

Do not open, mix, smell, or otherwise handle an unidentified or questionable chemical simply to determine what it is.

Follow the school's chemical safety and hazardous-waste procedures and have appropriately trained personnel evaluate it. Old, damaged, leaking, or unidentified chemicals may require special handling and disposal.

Can schools order laboratory labels in larger quantities?

Yes. Schools, universities, laboratories, and other organizations that need multiple rolls can consider bulk purchasing to maintain a consistent supply of labels across classrooms or departments.

View Colorty's Bulk & Business Orders →

What else should be labeled in a school laboratory besides chemicals?

In addition to chemicals, laboratories should label equipment, samples, tubes, vials, glassware, storage areas, freezers, cables, waste containers, and safety equipment. For a full breakdown, see our Laboratory Labeling Guide: What Should You Label in a Lab?