Ep. 23: Packing Groups Explained – How Dangerous Is Your Flammable Liquid?

Not all flammable liquids are created equal — and the packing group assigned to your chemical tells you exactly how dangerous it really is.

In this episode of Chemical Safety at Work, Patrick Gee breaks down what you must know about packing groups to stay compliant, avoid fines, and protect your workplace.

Find out:

• Why packing groups aren’t just about transport — they’re critical for storage too
• How to tell if your chemical is high, medium, or low danger
• Where to quickly find packing group info on your SDS
• How packing groups impact your minor storage limits and separation distances
• What happens if you get it wrong (hint: it’s serious)

If you’re storing, handling, or transporting dangerous goods — this is information you can’t afford to miss.

Read the blog here.

Listen now wherever you get your podcasts.

Chapters

• 0:00 Introduction to Packing Groups
• 1:43 Defining Packing Groups and Application
• 3:08 Flammable Liquids Classification Breakdown
• 4:35 GHS vs ADG Code Comparison
• 5:15 Common Chemicals and Storage Impact
• 6:35 Key Takeaways and Closing

Transcript

Patrick Gee: 0:06

Hey there and welcome to Chemical Safety at Work, the podcast that helps you understand dangerous goods, manage risk and build safer workplaces. I'm Patrick Gee, and today we're getting into something that's often overlooked but absolutely essential if you're working with flammable liquids. That's Packing Groups. Now, if you've ever looked at a safety data sheet and seen Packing Group II or PGIII and wondered what that really means for your site, this episode is for you. Let's dive into what packing groups are, why they matter and how they affect everything from your storage requirements to your separation distances. So what is a packing group?

Patrick Gee: 0:49

A Packing Group is a classification used to describe the degree of danger associated with a dangerous good during transport. They're part of the Australian Dangerous Goods Code, the ADG Code, and they apply across a range of substances, including Class III flammable liquids like ethanol, acetone and methanol. Packing Groups are shown in Roman numerals from I to III. Packing group I is high danger, packing group II is medium danger and packing group III is low danger. Understanding the packing group assigned to your flammable liquid tells you how dangerous it is to move and can also influence how you're allowed to store it, especially when it comes to things like minor storage and separation distances. Packing Groups help ensure that dangerous goods are transported safely both within Australia and internationally. The system is based on the UN model regulations, which provide standardised rules for packaging, lab labelling and containment of hazardous chemicals. But here's the thing they don't just apply during transport. The packing group of your chemical also plays a role in determining how much of the substance you can store in a minor storage area, how far your chemical store needs to be from protected places like offices or break rooms, and what kind of packaging and labelling is required to meet compliance. If you're not factoring in packing group when making decisions about chemical safety, you are flying blind.

Patrick Gee: 2:15

Let's look specifically at flammable liquids. Their packing group is determined by two key things Flash point, which is the lowest temperature at which the liquid gives off enough vapor to ignite, and initial boiling point, the temperature at which the liquid begins to boil. Here's the breakdown. Packing group one high danger flash point less than 23 degrees Celsius and boiling point less than or equal to 35 degrees Celsius. Packing group two medium danger flash point less than or equal to 35 degrees Celsius. Packing group II, medium danger Flash point less than 23 degrees Celsius, but boiling point greater than 35 degrees Celsius. Packing Group III, low danger Flash point equal or greater than 23 degrees Celsius and less than or equal to 60 degrees Celsius Celsius and less than or equal to 60 degrees Celsius. If the flashpoint is greater than 60 degrees Celsius but less than 93 degrees Celsius, you're likely dealing with a GHS category 4 flammable liquid not assigned a packing group but still considered hazardous under workplace chemical safety laws.

Patrick Gee: 3:23

You might have heard of GHS, the Globally Harmonised System for Classifying and Labelling Chemicals. So how does that compare to the ADG code? Here's the simple version GHS applies to hazardous chemicals in workplaces, covering storage, use and health risks. ADG applies to the transport of dangerous goods, including packaging, labelling and placarding. When it comes to flammable liquids, their GHS categories align closely with their ADG Packing Groups GHS1 is equal to Packing Group I, GHS2 equal to Packing Group II and GHS3 is equal to Packing Group III. So while the systems serve different purposes, they work together to keep your site safe and compliant. So, while the systems serve different purposes, they work together to keep your site safe and compliant.

Patrick Gee: 4:22

Let's take a look at a few common chemicals and their Packing Groups. Diethyl ether: Packing Group I. Acetone: Packing Group II. Methanol: Packing Group II. And ethanol: Packing Group II. Now remember you'll find the packing group in section 14 of your chemicals safety data sheet. That's the section that deals with transport information and for hazard identification. Head to section two. Always refer to your safety data sheet before moving, using or storing any dangerous goods. It's your key to understanding what you're working with.

Patrick Gee: 5:02

The Packing Group of a flammable liquid also impacts how much you're allowed to store. Of a flammable liquid also impacts how much you're allowed to store, especially in minor storage areas. For example, Packing Group I liquids in containers larger than 2.5 litres generally shouldn't be kept in minor storage areas unless they're essential to daily operations and handled by trained personnel. Packing Group can also affect spill containment requirements, storage cabinet design and separation distances from public spaces, walkways or protected areas. So again, understanding your chemicals Packing Group is about more than just transport. It's about total site safety. So, let's wrap up.

Patrick Gee: 5:48

Packing Groups tell you how dangerous a substance is during transport. But they also influence how you store, handle and manage that substance day- to- day. For flammable liquids, Packing Group I is high danger, Packing Group II means medium danger and Packing G roup III is low danger. You can find the Packing Group on the SDS and, if you're not sure, check the ADG Code or talk to a dangerous goods consultant. That's it for this episode of Chemical Safety at Work. If you found this week's episode helpful, please subscribe to Chemical Safety at Work on your favourite podcast platform and rate or leave us a review. We'd love to from you, so send us a message and let us know if there are any topics you'd love us to dive into. As always, stay safe, stay compliant and remember every label, every SDS and every storage decision matters. Catch you next time.