Friable vs Non-Friable Asbestos: The Difference Between Class A and Class B Asbestos Removal

Asbestos types explained

There are six mineral types of asbestos, but for removal, what matters is the condition of the material it’s in.

In New Zealand, friable asbestos is called Class A and non-friable asbestos is called Class B. WorkSafe’s rule of thumb is simple: if a dry material can be crumbled or turned to powder with hand pressure alone, it’s friable.

If you’re wondering what Class A asbestos is and what Class B asbestos is, the short answer is friable and non-friable. You may also see ‘Grade A’ and ‘Grade B’, but Class A and B are the New Zealand terms.

What is Class A asbestos?

Class A asbestos is also known as ‘friable asbestos’ because it is very prone to crumbling into a powder when it’s dry.

Because it is so delicate and easy to crumble, it releases asbestos fibres into the atmosphere more quickly and easily. It takes very little movement for this kind of asbestos to fall apart, and therefore be inhaled by people or animals in the area.

What is friable asbestos?

Friable asbestos crumbles very easily and often ends up as a ‘dusty’ material. This makes Class A asbestos especially dangerous because it releases more easily into the air, making exposure more likely as it settles on surfaces and is inhaled by people and animals.

And you can’t see the danger. Airborne fibres are usually too small to see with the naked eye, so a room that looks clean can still carry them.

The types of Class A asbestos products

Class A asbestos often turns up in places homeowners don’t expect. For example, practically any kind of Class B asbestos can become Class A asbestos once it deteriorates.

Asbestos-contaminated dust (ACD) is considered Class A asbestos and can also come from Class B asbestos products. So if a Class B cement sheet deteriorated into a fine powdery dust, it would be classified as a Class A product.

Other common Class A asbestos products include:

• Textured ‘popcorn’ ceilings, including brands like Glamatex and Whisper
• Vinyl flooring with asbestos paper backing
• Materials used in thermal insulation, such as hot water pipe lagging and insulation around old heaters and fireplaces
• Spray-on coatings
• Mill board/asbestos insulation board
• Asbestos textiles/ropes/blankets
• Loose-fill insulation in roof spaces

If any of these are in your home or building, our Class A asbestos removal team works under full containment every time.

What is Class B asbestos?

Of the two types of asbestos, Class B is considered to be less dangerous. That’s because it is, by definition, ‘non-friable’.

What is non-friable asbestos?

Non-friable asbestos is somewhat less dangerous than its Class A cousin because the asbestos fibres are bonded tightly to the main material. For example, Class B asbestos is usually found mixed into products such as plastic or cement, so it is ‘bonded’ to the actual plastic or cement, and therefore less likely to be crushed into dangerous dust.

Class B asbestos is the kind that is considered ‘safe’ if it is left undisturbed, because it’s not going to crumble and become dangerous on its own. The trouble is that most renovation work involves exactly the kind of cutting, drilling, and sanding that disturbs it.

Class B asbestos still requires skill and the right qualifications and tools to remove, but it is fortunately less dangerous than Class A asbestos.

Types of Class B asbestos products

Class B is the most common kind in NZ homes. Here are the non-friable asbestos examples we come across most often in Wellington:

• Vinyl composite tiles (VCT)
• Electrical resin products, such as old meter boards and switchboard backings
• Cement sheets, including Fibrolite linings in bathrooms, kitchens, and laundries
• Cement pipes, gutters, and roofing products, like Super Six roofing
• Bituminous products
• Exterior cladding, soffits, and fence panels
• Garage, carport, and shed linings

For anything on this list, our Class B asbestos removal service covers everything from a single shed to full re-roofs and re-cladding.

The difference between Class A and Class B asbestos at a glance

Here’s a side-by-side summary of friable vs non-friable asbestos and what each one means for your project:

When Class B asbestos becomes Class A

Class B asbestos products can degrade over time and become Class A asbestos, so you should never underestimate the hazardous nature of this kind of asbestos.

Decades of Wellington wind and rain can leave old cement roofing brittle and crumbling. Water damage, earthquake damage, fire, and DIY sanding or water blasting can all do the same.

Say a Fibrolite bathroom wall has been soaked by a leaking shower for years. If it’s gone soft and crumbly, removal will likely need a Class A approach.

Asbestos removal Class A and Class B: who can remove what?

Licensed asbestos removal in New Zealand works a bit like a driver’s licence, where the class decides what you’re allowed to do. A Class A licence holder can remove both friable and non-friable asbestos. A Class B licence holder can only remove non-friable asbestos.

Some asbestos removal specialists only remove Class B asbestos. Removing Class A asbestos requires additional training, expertise, and safety equipment, so you need to know which class is present on your property before hiring an asbestos remover.

Can I remove asbestos myself?

Less than 10m² of non-friable asbestos can be removed without a licence. You still need to follow safe work practices, wear the right protective gear, and dispose of the waste correctly. Friable asbestos is a different story, and any amount requires a licensed Class A removalist.

Who signs off the clearance?

Before anyone moves back in, the area has to be cleared. For Class A work, that’s done by an independent licensed asbestos assessor, who inspects the area and carries out air monitoring. Class B work can be cleared by an independent competent person.

You can check any removalist’s licence on WorkSafe’s asbestos licence holder register before you hire.

How do you find out which class you have?

You can’t know which type of contaminant is present without a test, so keep in mind that even professionals can’t usually assign a class without testing the material first.

The only way to tell the difference is with expert asbestos testing. We collect samples on site and send them to an accredited laboratory for analysis, so you get a clear answer before any work starts.

Please don’t take samples yourself. Breaking off suspect material can release the very fibres you’re trying to avoid.

Class A and Class B asbestos removal, handled by one Wellington team

PRO Environmental Services is a Class A and Class B asbestos removal company. We can safely remove any kind of asbestos from your property, and we work alongside your independent assessor to clear the site and get it ready for you to move back in.

We handle asbestos, demolition, and environmental cleanup as one team, so you get one quote from testing through to the final clean. We cover Wellington, the Hutt Valley, Kāpiti, and the Wairarapa.

Get in touch anytime for a free quote or to learn more about our asbestos removal services.