How to Choose the Right Nitric Acid Concentration for Your Application

Choosing the right nitric acid concentration depends on your application, since using the wrong strength can mean poor results or unnecessary safety risk.

Nitric acid is sold in several concentration bands, from dilute laboratory grades through to highly concentrated, tightly regulated industrial grades.

Matching the concentration to the job, rather than defaulting to the strongest option available, is usually the safer and more cost-effective choice.

What Is Nitric Acid and Why Does Concentration Matter?

Nitric acid (HNO₃) is a strong mineral acid and powerful oxidiser used widely across manufacturing, laboratories, and metal treatment industries.

Most businesses buy nitric acid based on the specific concentration their process requires, rather than a single default strength.

Concentration affects reactivity, corrosivity, and how the acid needs to be stored and handled, so getting it right matters as much as sourcing a reliable, consistent supply.

Common Nitric Acid Concentrations and Their Applications

Nitric acid is typically sold in four broad concentration bands, summarised below.

Concentration	Common Name	Typical Uses	Handling Note
5%-20%	Dilute	pH adjustment, light cleaning, lab reagent dilution	Lower fuming, easier to handle
20%-50%	Medium	Metal treatment, general industrial processing	Moderate corrosivity, standard PPE required
68%-70%	Concentrated	Metal passivation, analytical chemistry, manufacturing	Most common commercial and lab grade
Above 90%	Fuming	Specialised industrial and aerospace processes	Heavily regulated, restricted access

Dilute Nitric Acid (5%-20%)

Dilute nitric acid suits lighter tasks such as pH adjustment, general cleaning, and preparing lab solutions where a strong oxidiser would be excessive or unnecessary.

Medium Concentration (20%-50%)

Medium-strength nitric acid is common in metal treatment and general industrial processing, offering more reactivity without the storage and handling demands of higher grades.

Concentrated Nitric Acid (68%-70%)

Concentrated nitric acid, the most widely available commercial grade, is used for metal passivation, analytical testing, and broader manufacturing processes across many industries.

Fuming Nitric Acid (Above 90%)

Fuming nitric acid supports specialised industrial and aerospace applications, and access is tightly restricted under Australian dangerous goods and precursor chemical regulations for good reason.

Factors to Consider When Choosing the Right Nitric Acid Concentration

How to choose the right nitric acid for your work comes down to a few practical questions, rather than simply picking the strongest grade available on the shelf.

• What reaction or process does the acid need to support, and what concentration does that process actually call for?
• What safety equipment, ventilation, and storage capacity do you have available on site?
• Would a milder product, such as hydrogen peroxide 3%, actually suit the task better than a strong acid?

Answering these honestly, before placing an order, usually points to a lower concentration than most people initially assume.

Safety Tips When Handling Different Nitric Acid Concentrations

Higher concentrations demand more caution, but even dilute nitric acid requires proper handling to avoid skin burns or fume exposure over time.

• Wear acid-resistant gloves, goggles or a face shield, and a lab coat or apron suited to the concentration in use.
• Work in a well-ventilated area or fume hood, especially with concentrated or fuming grades.
• Store away from metals, organic materials, and bases, and keep a neutralising agent such as calcium hydroxide on hand for spill response.

Following these basics reduces most of the risk associated with everyday handling, regardless of which concentration you're working with.

Where to Buy Nitric Acid in Australia

Where to buy nitric acid matters almost as much as which concentration to choose, since nitric acid is a regulated dangerous good in Australia, not an unrestricted commodity chemical.

Nitric acid sits on the Poisons Standard and is classified as a dangerous good, so reputable suppliers request identification and details about intended use before despatch.

This isn't unusual. It's standard practice across the industry and reflects the regulatory requirements that apply to hazardous chemicals more broadly.

Why Choose All Chemicals for Nitric Acid Supply?

All Chemicals supplies nitric acid across the dilute, medium, concentrated, and fuming grades covered above, with a Safety Data Sheet and Certificate of Analysis provided for every order.

Packaging is matched to the concentration purchased, and deliveries are handled under standard dangerous goods requirements.

Based in Perth, All Chemicals supplies businesses and laboratories across Australia and can advise on which concentration suits a specific process before ordering.

Choosing the Right Concentration: Key Takeaways

Getting the concentration right starts with the application, not the strongest product on the shelf.

Dilute grades suit light tasks, medium and concentrated grades cover most industrial and lab work, and fuming grades stay reserved for tightly regulated, specialist applications only.

Checking your process requirements against the table above is usually enough to land on the right grade the first time.