What are the different types of asbestos air monitoring? (And which do I need?)

When handling asbestos-containing materials (ACMs), several safety practices are put into place. Air monitoring is one of them, and it’s an important aspect of ensuring everyone’s health and well-being.

In its undisturbed and undamaged state, asbestos isn’t dangerous. But if an ACM is damaged in some way, it can release microscopic asbestos fibres into the air. They can then be inhaled or ingested and stick to a person’s lungs, which can lead to life-threatening diseases years in the future.

Airborne asbestos fibres are extremely dangerous. That’s why air monitoring before, during, and after asbestos work is an important part of keeping everyone safe.

In this article, we’ll discuss the different types of asbestos air monitoring procedures used in commercial buildings. To ensure workspace safety and stay compliant with asbestos regulations, the correct air monitoring procedure must be used.

asbestos air testing

What happens during asbestos air monitoring?

Asbestos air monitoring is typically carried out by a professional. The core competencies that are recommended for asbestos experts conducting air sampling include:

  • Properly setting up air monitoring equipment
  • Accurately preparing samples and counting the fibres in the samples
  • Calculating the concentration of fibres in the air
  • Understanding common sampling errors and how to avoid them
  • Clearing the area of fibres so it can be occupied post-removal

It’s also important that any asbestos worker in charge of air monitoring has high standards for site cleanliness, as well as the know-how to keep accurate, detailed records.

After air monitoring is concluded, the results should be kept for at least five years. Depending on the circumstances, they may need to be kept for longer. Additionally, air monitoring results must be made available to anyone involved with or affected by the site where the testing took place.

Besides making a site safe for employees, residents, and visitors, air monitoring also keeps workers safe. According to the Control of Asbestos Regulations 2012 (CAR), the risk to workers must be minimised. Air monitoring is used to determine if the safety controls and protective equipment used are sufficient for the amount of asbestos in the air. For example, the type of mask and respiratory protective equipment (RPE) selected for the asbestos-related job will be chosen based on risk level, and air monitoring results will impact the decision.

What are the different types of asbestos air monitoring?

Next, let’s go over the different types of asbestos air monitoring.

Note that while air monitoring finds the concentration of asbestos fibres in the air, non-asbestos fibres may also be present. To come to a reliable conclusion, professionals will collect information about all the fibres present.

Asbestos background air monitoring

Background air monitoring is an important process that’s used to assess the baseline air quality before any asbestos removal takes place. Monitoring will continue while the asbestos work is being done.

The purpose of background air monitoring is to determine if the asbestos work that’s taking place is being done carefully and using proper control measures. The concentration of airborne fibres should remain under a certain level to prevent health problems.

Asbestos leakage air testing

Commonly, licensed asbestos work takes place in an enclosed, airtight, purpose-built area. The asbestos enclosure should have an air-management system specifically for dealing with asbestos fibres, keeping fibres from getting into areas outside the enclosure. Leakage air testing is used to ensure that air outside the enclosure remains unaffected.

Asbestos control air monitoring

Control air monitoring verifies that the asbestos fibres in the air fall below a specific level post-removal. It’s sometimes referred to as clearance monitoring instead. This process should lead to a certificate that shows the space can be occupied once again.

Any licensed asbestos work that takes place in an enclosure legally requires a four-stage clearance test. Stage 3 is clearance air testing, and the procedure must find specific results to pass:

  • The sample volume must be at least 480 litres of air
  • There must be less than .01 fibres per millilitre of sampled air

Only when the results match the requirements can an area be considered safe for reoccupation.

Asbestos personal air testing

Personal air testing monitors the air that a worker breathes in. That person may work directly with ACMs, or they may be a non-asbestos worker in the vicinity. This type of air monitoring can help determine whether the protective measures being used are effective enough. Personal air testing can also show if RPE is functioning properly.

Asbestos reassurance air monitoring

There are a few situations when reassurance air monitoring is used:

  • An asbestos job took place, and the air needs to be tested to confirm that there aren’t dangerous levels of fibres in the air.
  • There’s been an accident, and ACMs are damaged, so the air needs to be tested to determine if fibres were released.
  • The building contains asbestos, and even though it’s undisturbed, the dutyholder wants to ensure there aren’t fibres in the air.

Reassurance air monitoring is also part of the legally required four-stage clearance process post-removal in an enclosed area.

How do I choose the right type of air monitoring for my situation?

While there are different names for asbestos air testing, they generally follow the same method to test for fibre levels in the air. Basically, any type of asbestos air test has the same goal: To show the concentration of the asbestos fibres in the air at a given time.

The purpose of assigning different names to air testing is mainly to clarify what the customer needs from the test. Then, the asbestos air monitoring company can adapt its approach and equipment based on the asbestos project at hand and the desired outcome.

The type of asbestos test you need is based on your current asbestos situation and any plans you may have for dealing with ACMs. For example:

  • If you know that you need asbestos removal, then background air monitoring is the type of test to inquire about.
  • In the case of high-risk asbestos work, control or clearance monitoring is a legal requirement.
  • You may not have any asbestos removal or building renovation plans. Instead, you simply want to know if you should worry about breathing in asbestos fibres. Reassurance monitoring is likely the right choice.

Speaking with an asbestos professional will help you figure out which type of asbestos test is the best option for your situation.

What happens if asbestos is detected in air monitoring?

What if asbestos air testing shows that there’s too high a concentration of asbestos fibres in the air? The next step is to lower the concentration so the area is safe to occupy. Here are a few examples of what may happen:

  • Background air monitoring or leakage air testing shows that there are too many fibres in the air during an asbestos removal job. The work may need to be put on pause so a better air management system can be set up.
  • After the asbestos work is complete, control air monitoring determines there are still fibres in the air. The work site will need to be re-cleaned and re-tested until the concentration is at a safe level.
  • Personal air testing shows an individual is breathing in asbestos. The work may need to stop until better RPE is attained.

The type of air testing used and its results will determine the next steps. In some cases, a certain amount of asbestos is expected in the air, like while work is occurring. At other times, there shouldn’t be any fibres in the air, so the solution will be in accordance with reasonable expectations.

What are the legal requirements for asbestos air monitoring in the UK?

Asbestos air monitoring is considered a low-risk type of work. That means that, according to CAR, this type of work doesn’t require notifying the authorities. To remain compliant, though, asbestos air testing can only be done by a company with a United Kingdom Accreditation Service (UKAS) accreditation, according to CAR.

The records for air testing that’s done for the purpose of confirming if an employee was exposed to asbestos must be retained for 40 years. The employee is also allowed to request access to those records. Otherwise, basic air testing records should be retained for at least five years.

Final thoughts about asbestos air monitoring

It’s important to select the right type of air monitoring you have done so the accredited company can tailor the results to your needs. For example, personal air testing considers what an individual is breathing in during the workday. Reassurance testing determines if an area where asbestos was damaged has been impacted by airborne fibres.

Never try to conduct asbestos air testing on your own. The only way to keep yourself and others safe is by using an accredited company. Professional asbestos workers provide a wide variety of specialty services. Often, that includes air monitoring and sampling.

For more information about asbestos air monitoring, contact a specialist today.

What are the different types of asbestos air monitoring? (And which do I need?) 1

Written by Jess Scott

Jess Scott has been an all-round asbestos consultant since 1996. That’s nearly 3 decades of asbestos knowledge. He spends his time sharing that knowledge with the team at Oracle and with their clients. Jess's goal is, and always has been, to use my expertise in helping people to comply with the law. This legal compliance ultimately helps to protect everyone from the harmful effects of asbestos. Jess has acted as an asbestos expert witness in legal cases and is involved in many asbestos educational activities throughout the UK.