How to Properly Store Isopropyl Alcohol at Home

Isopropyl alcohol is a remarkably useful chemical to have on hand, but its properties—particularly its flammability and tendency to evaporate—mean that proper storage is essential. Whether you keep a small bottle for occasional first aid use or maintain bulk supplies for your workshop, understanding how to store IPA correctly ensures both safety and product effectiveness.

Understanding IPA's Storage Challenges

Before discussing storage solutions, it's helpful to understand why IPA requires specific storage conditions:

• Flammability: IPA has a flash point of about 12°C (53°F), meaning it can ignite at room temperature when exposed to a spark or flame
• Volatility: IPA evaporates readily, even at room temperature. An improperly sealed container will gradually lose its contents to the air
• Hygroscopic nature: IPA absorbs moisture from the air. Over time, this can reduce the concentration and effectiveness of high-purity IPA
• Light sensitivity: While less critical than for some chemicals, prolonged UV exposure can degrade IPA over time

Choosing the Right Container

The container you use for storing IPA significantly impacts both safety and product longevity.

Recommended Container Materials

• HDPE (High-Density Polyethylene): The most common material for IPA containers. Chemically resistant, impact-resistant, and affordable. Look for containers marked with recycling code #2
• Glass: Excellent chemical resistance and doesn't absorb odours. However, breakage risk makes glass less ideal for larger quantities or workshop environments
• Metal (lined): Stainless steel or appropriately lined metal containers work well for bulk storage. Ensure the container is specifically rated for flammable solvents

Containers to Avoid

• PVC: Can be degraded by IPA over time
• Polystyrene: IPA will dissolve or cloud this plastic
• Regular glass bottles: Without proper lids, evaporation is rapid. Also pose breakage risk
• Food or beverage containers: Never store chemicals in containers that could be confused with drinks

Ideal Storage Location

Where you store IPA is just as important as what you store it in. The ideal storage location meets several criteria:

Temperature Considerations

Store IPA at stable, moderate temperatures. The ideal range is 15-25°C (59-77°F). Avoid:

• Direct sunlight or near windows
• Near heaters, radiators, or hot water systems
• In vehicles (temperature extremes)
• In sheds or garages that experience extreme heat in summer

While IPA doesn't freeze at typical household temperatures (freezing point is approximately -89°C), temperature fluctuations can cause container expansion and potential leakage.

Ventilation

Even sealed containers can release small amounts of vapour. Store IPA in areas with adequate ventilation to prevent vapour accumulation. Avoid enclosed spaces without airflow, such as:

• Sealed cupboards under sinks
• Airtight storage boxes
• Small utility closets without vents

Distance from Hazards

Keep IPA away from potential ignition sources:

• Maintain at least 3 metres from open flames, gas appliances, and pilot lights
• Keep away from electrical equipment that may spark
• Store separately from oxidising agents (bleach, hydrogen peroxide, pool chemicals)
• Keep away from strong acids and bases

Storage Quantities and Regulations

The amount of IPA you store at home determines what precautions are necessary. In Australia, storing flammable liquids like IPA may be subject to local regulations.

General Home Use (Under 5 Litres)

For typical household quantities, standard safety practices are usually sufficient. Keep containers sealed, store in appropriate locations, and maintain good ventilation.

Larger Quantities (5-25 Litres)

Consider investing in a flammable liquids cabinet. These purpose-built storage units feature:

• Self-closing doors
• Spillage sumps
• Ventilation provisions
• Fire-resistant construction

Bulk Storage (Over 25 Litres)

Storing large quantities may require compliance with Australian Standard AS 1940 and local council regulations. Consider consulting with your local fire authority or a WHS professional for guidance on requirements in your area.

Shelf Life and Effectiveness

A common question is whether IPA "goes bad." The answer is nuanced:

Unopened Containers

Properly sealed IPA can last 2-3 years or longer without significant degradation. The product doesn't decompose, but over very long periods, trace contaminants and slow evaporation through the seal can affect purity.

Opened Containers

Once opened, IPA begins to absorb moisture from the air and evaporate. The rate of degradation depends on:

• How often the container is opened: Frequent use means more air exposure
• How tightly it's sealed: Poor seals accelerate evaporation
• Environmental humidity: Higher humidity means faster moisture absorption
• Container fill level: More headspace means more air exposure

For most practical purposes, opened IPA remains effective for 6-12 months with proper storage. You might notice slight changes in concentration over time, but it remains useful for most applications.

Preventing Evaporation Loss

Evaporation is the primary way IPA is lost during storage. Minimise losses with these practices:

• Keep containers tightly sealed: Always replace caps immediately after use
• Use containers with good seals: Replace containers with worn or damaged lids
• Minimise headspace: If you're storing less than a full container, consider transferring to a smaller container
• Store in cool conditions: Higher temperatures increase evaporation rate
• Use pump dispensers for frequent use: These minimise air exposure compared to repeatedly opening lids

Labelling and Safety Information

Proper labelling is both a safety requirement and good practice:

• Keep original labels: They contain important safety information and first aid instructions
• Label secondary containers clearly: If you transfer IPA, label the new container with the contents and concentration
• Include hazard warnings: "Flammable" and "Keep away from heat/flames" at minimum
• Date opened containers: This helps track freshness

Special Situations

Storing with Other Chemicals

If you store multiple chemicals, keep IPA separate from oxidisers and corrosives. A dedicated shelf or section for flammable solvents is ideal.

Workshop or Garage Storage

Workshops present specific challenges: temperature swings, potential ignition sources, and the presence of other chemicals. Consider a dedicated flammable storage area with proper ventilation and clearly marked boundaries.

Travelling with IPA

If you need to transport IPA, keep quantities small, ensure containers are tightly sealed, and never leave them in hot vehicles. Airlines prohibit IPA in luggage due to flammability.

Conclusion

Proper storage of isopropyl alcohol isn't complicated, but it does require attention to a few key factors: appropriate containers, suitable locations, and awareness of quantity-related regulations. By following the guidelines in this article, you'll maintain both safety and product effectiveness.

Remember: IPA is a useful household and workshop chemical, but its flammable nature demands respect. Store it thoughtfully, and it will serve you well for its many applications.