Beginner's Guide to Isopropyl Alcohol

If you've ever cleaned a wound, wiped down your phone screen, or prepared a surface for painting, chances are you've encountered isopropyl alcohol. This remarkable chemical compound has become a household staple around the world, yet many people don't fully understand what it is or how to use it effectively. This guide will give you a solid foundation in everything IPA, setting you up for safe and effective use.

What Exactly Is Isopropyl Alcohol?

Isopropyl alcohol, often abbreviated as IPA, is an organic compound with the chemical formula C3H8O. It belongs to a family of chemicals called alcohols, but unlike ethanol (the alcohol in beverages), isopropyl alcohol is not safe to drink. In Australia and elsewhere, you might also hear it called:

• Isopropanol - its chemical name
• Rubbing alcohol - a common household term
• IPA - the industry abbreviation
• Propan-2-ol - its systematic chemical name

IPA is produced industrially through the hydration of propylene, a by-product of petroleum refining. It's a colourless liquid with a distinctive sharp, slightly sweet odour that most people find recognisable once they've encountered it.

Understanding Concentrations: The Numbers Matter

When you shop for isopropyl alcohol, you'll notice products come in different concentrations, typically 70%, 91%, or 99%. These percentages indicate how much of the solution is pure IPA versus water or other additives. Choosing the right concentration depends entirely on what you plan to use it for.

70% Isopropyl Alcohol

This is the most common concentration for household disinfection and first aid. The 30% water content actually makes it more effective at killing bacteria and viruses than higher concentrations. Why? Water helps the alcohol penetrate the cell walls of microorganisms, allowing it to denature their proteins more effectively. The slower evaporation rate also gives it more contact time with surfaces.

Best uses: Disinfecting surfaces, cleaning minor wounds, sanitising hands, general household cleaning.

91% Isopropyl Alcohol

This concentration offers a balance between cleaning power and evaporation speed. It's more versatile than 70% for non-biological applications while still being readily available at most pharmacies.

Best uses: General-purpose cleaning, light electronics cleaning, removing sticky residue, cleaning tools.

99% Isopropyl Alcohol

The highest concentration commonly available to consumers, 99% IPA evaporates extremely quickly and leaves virtually no residue. This makes it ideal for applications where any moisture could cause damage.

Best uses: Cleaning sensitive electronics, removing thermal paste, 3D printing cleanup, laboratory applications, precision cleaning.

Common Uses for Isopropyl Alcohol

The versatility of IPA is truly impressive. Here's an overview of its most popular applications:

Healthcare and First Aid

In medical settings and homes alike, 70% IPA is used to disinfect skin before injections, clean minor wounds, and sanitise medical equipment. It's also a key ingredient in many commercial hand sanitisers. However, it's important to note that while IPA can help clean wounds, it should not be used deep inside wounds and isn't a substitute for proper medical care.

Electronics Cleaning

The quick evaporation of high-concentration IPA makes it perfect for cleaning electronics without risking moisture damage. It effectively removes dust, fingerprints, and grime from:

• Computer keyboards and mice
• Smartphone and tablet screens (applied to cloth, not directly)
• Circuit boards and connectors
• Game controllers
• Camera equipment

3D Printing

The resin 3D printing community relies heavily on IPA. After a print is completed, the piece is covered in uncured liquid resin that must be washed off before final curing. 91% or 99% IPA is the standard cleaning solution for this purpose. It's also used to clean the resin vat and build plate between prints.

Household Cleaning

Around the home, IPA excels at tasks that other cleaners struggle with:

• Glass and mirrors: Leaves streak-free surfaces
• Stainless steel: Removes fingerprints and smudges
• Sticky residue: Dissolves adhesive left by stickers and tape
• Permanent marker: Removes marks from many surfaces
• Disinfecting surfaces: Kills most common household germs

Automotive and Workshop

Mechanics and DIY enthusiasts use IPA for degreasing parts, preparing surfaces before painting or applying adhesives, and cleaning tools. Its quick evaporation makes it particularly useful when you need a surface dry and residue-free quickly.

What Isopropyl Alcohol Cannot Do

While IPA is versatile, it's not a miracle solution. Understanding its limitations helps you use it appropriately:

• It's not effective against all germs: Some bacterial spores and certain viruses are resistant to IPA
• It doesn't remove all stains: Organic stains like blood or grass often need different treatments
• It can damage some materials: Certain plastics, painted surfaces, and finishes may be harmed by IPA
• It's not a substitute for soap and water: For dirty hands, washing is more effective than sanitising

Where to Buy Isopropyl Alcohol in Australia

Finding IPA in Australia is straightforward, with several options depending on your needs:

Pharmacies

Chemist Warehouse, Priceline, and local pharmacies typically stock 70% rubbing alcohol in small bottles. This is the easiest option for first aid and light household use. You may need to ask at the counter for 91% or higher concentrations.

Hardware Stores

Bunnings and other hardware retailers carry IPA in larger quantities, often sold as "methylated spirits" or under brand names like Diggers. These are typically higher concentrations suitable for cleaning and workshop use.

Online Retailers

Amazon Australia and specialty suppliers offer the widest range of concentrations and quantities. Online shopping is particularly useful if you need 99% IPA or bulk quantities, which may not be available in physical stores.

Specialty Stores

Electronics shops, 3D printing suppliers, and scientific supply companies often stock high-purity IPA tailored to specific applications.

Basic Safety Reminders

Even as a beginner, it's crucial to develop good safety habits from the start:

• Ventilation is key: Always use IPA in well-ventilated areas
• Keep away from flames: IPA is highly flammable—never use near heat sources
• Protect your skin: Wear gloves for extended use to prevent drying
• Store properly: Keep containers sealed in a cool, dark place
• Keep away from children: IPA is toxic if ingested
• Never mix with bleach: This creates dangerous toxic gases

Your First Steps with IPA

Ready to start using isopropyl alcohol? Here's a suggested approach for beginners:

1. Start with 70% IPA: It's the safest concentration and most versatile for household use
2. Buy a small quantity: A 500ml bottle is plenty to start with
3. Get a spray bottle: Decanting into a spray bottle makes application easier and safer
4. Practice on safe surfaces: Start with glass and stainless steel before trying on delicate items
5. Read up on specific applications: Check our other guides for detailed instructions on electronics, first aid, and more

Conclusion

Isopropyl alcohol is a remarkably useful addition to any household or workshop. By understanding the different concentrations, appropriate applications, and basic safety practices, you're now equipped to use IPA effectively and safely. Whether you're disinfecting surfaces, cleaning electronics, or tackling stubborn residue, the right IPA product can make the job easier.

As you become more comfortable with isopropyl alcohol, explore our other guides for detailed instructions on specific applications. Welcome to the world of IPA—one of the most practical chemicals you'll ever use.