After mold remediation, it is always advisable that you test for mold. This serves two purposes. The first is that it ensures that your home is free of the toxicity or allergy-inducing effects of mold. And if you hired a mold remediation company, carrying out post-remediation mold testing determines whether they did a good job getting rid of the mold from your home.

Here is what you should know about mold post-remediation inspections and why they are worth your time.

mold inspection

While the rules to carrying out a post-mold remediation inspection are not set in stone, there are general guidelines that should be followed if you want to have reliable results.

For starters, the mold clearance area needs to be sealed off in order to avoid cross-contamination from other building areas. To also minimize the chances of getting inaccurate results from contamination, these inspections are also typically carried out within a 48-hour window after remediation. However, the area is usually allowed about 24 hours for the dust to settle and in order to have “still air”.

After observing the above guidelines, the process is usually carried out in the following sequence.

Visual inspection

A visual inspection of the mold clearance area is typically the first step in the post-remediation mold inspection process. In this step, the inspection company simply observes the visual cleanliness of the area. This includes looking for obvious moldy growth and presence.

They also visually inspect and make notes on other areas of the building. They take note of leaks and other conditions that might increase the likelihood of having a mold regrowth. And since such inspections are usually carried out before the area’s mold containment system is removed, observing the integrity of the system is also done at this stage.

Collection of surface samples

After carrying out a visual inspection, it is time to test whether physical surfaces have traces of mold. To this end, the inspectors will collect samples from exposed surfaces or surfaces that they suspect are prone to mold growth.

In order to get a good baseline for gauging the effectiveness of the cleanup process, they will also collect samples from physical spaces outside the working area. These samples usually come in handy in comparing environments. They also help to determine the effectiveness of the mold remediation company’s mold containment efforts.

Post Remediation Mold Testing

Collection of air samples

Samples from physical surfaces are not enough. This is because in some cases, existing conditions like running air conditioning systems, air scrubbers, open windows, and fans can keep dust and other air contaminants from settling. Therefore taking a sample of the air is necessary. This includes samples from neighboring rooms or homes that are outside the work area.

Inspection of the property’s vulnerability to mold

While this step is not necessary when it comes to evaluating the mold remediation company’s work, it comes in handy when writing the inspection report. This is because by observing potential problem areas, the inspectors will be in a good position to make useful recommendations.

For example, they can note flooding risks or plumbing risks that encourage growth. Areas that are prone to experiencing high humidity can also be pointed out. And recommendations such as structural fixes or using dehumidifiers can be made as a result.

Inspection of the propertys vulnerability to mold

Processing of collected samples

The next stage is to take the collected samples to a lab and then process it. The samples are usually treated with stains and then observed under a microscope. In the lab, all they want to determine if the concentration of mold spores. Some labs go a step further and test for the types of mold, and compare the concentrations within the work area, to levels outside.

Report preparation

After laboratory testing, the last stage involves report preparation. In this stage, the testing company compiles all the data, analyzes it, and presents the findings in the form of a report.

In the report, they include their opinion on whether the mold remediation job was satisfactory. They sometimes also include their recommendations, especially with regards to improvements that can be made to discourage mold attacks.

Do I really need a post-mold remediation inspection?

Yes. A post-remediation mold inspection helps to let you know whether a mold clearance job has been effective.

An inspection is also necessary to help you know whether there was cross-contamination. This is something that usually occurs in cases where there are inadequate containment systems. Therefore, doing such an inspection can help you know where to focus your mold cleaning efforts.

Since post-remediation inspection reports sometimes include observations and recommendations with regard to the general state of the property, they can help you to know what to do next. Whether it is fixing leaking pipes, taking steps to prevent basement flooding, or simply replacing the filters of your A/C, these recommendations can make mold prevention easier.

Do I really need a post remediation inspection woman shows the mold

What is a mold clearance test?

A mold clearance test is a test that is designed to determine whether a mold remediation process has been successful. It typically involves the collection of samples from physical spaces and air samples.

These samples are then analyzed in a laboratory and then compared to those collected outdoors. The comparison is then used to determine whether remediation was successful enough to get rid of toxic or allergy-triggering mold levels inside a space.

However, a clearance test doesn’t always stop at determining whether mold remediation work. It is useful in figuring out whether cross-contamination occurred. It also tends to involve carrying out an inspection of the space in a bid to identify the source of the mold problem.

These tests are typically carried out by companies that are independent of the contractors who worked on the space. This is so as to guarantee the integrity of the tests. And they are usually necessary to give a homeowner peace of mind. Homeowners can also use them to determine whether or not to pay mold remediation contractors the full amount.

Is there a warranty on mold remediation?

Yes, a significant number of contractors offer warranties for their mold remediation services. These warranties typically cover a time frame that ranges between 3 years and 5 years. Essentially, the warranty provides that if mold growths occur in areas that they have worked on and treated, one can either get a refund or free remediation services.

However, reputable companies don’t usually offer warranties that guarantee that they will remove 100% of the mold from a property. This is because it is an impractical promise since mold spores exist naturally in the environment — both indoors and outdoors.

How long does mold remediation last?

Mold remediation typically lasts between 1 day and 5 days. In some cases, it can take no more than a few hours. it all depends on the size of the area that has to be worked on and the level of mold growth.

The size of the crew that is working on the area also matters. This is because a crew of 10 can do a job faster than one that is composed of only 3 people.

What level of post-remediation mold is safe?

Generally, mold spore concentrations that are less than or at least equal to spore concentrations outside are what is considered safe.

This is the main reason why post-remediation mold testing usually involves collecting samples from both the work area and the outside area. The outside area spore concentrations are usually considered as a baseline when determining the effectiveness of mold remediation.

Concentrations that fall below 1500 spores/m3 are usually considered normal and safe. This is so especially if they are of the most common species — Penicillium/Aspergillus.

However, even the smallest concentrations of Stachybotrys can be a sign of trouble since this species is toxic and doesn’t usually exist naturally.


Yes, it is safe to sleep in a house with mold if the mold concentration in the air is low. Why? because mold spores occur naturally, even outside, and for as long as the spore/m3 levels are below 1500, you shouldn’t worry.

However, if the mold levels are above 1500 spores/m3, or if there are traces of toxic species like Stachybotrys, it is not safe.

High concentrations of even the commonly-occurring Penicillium/Aspergillus species are likely to cause severe allergic reactions. As for the toxic mold species, even mild concentrations can lead to serious respiratory complications.

Mold removal typically takes between 1 day and 5 days. However, this period varies widely depending on the size of the area from which the mold has to be removed.

Other factors that also affect the length of the period include: where the mold is located, the number of people removing the mold, and how extensive the mold infestation is.

Yes, you can remove mold yourself.

To do so safely, you will have to wear protective gear like rubber gloves and eyewear protection. You will also need to shield the moldy area from the rest of your home by using appropriate mold containment systems like layers of plastic sheeting.

To do so effectively, you will need a solution or chemical that can kill mold. Homemade solutions, like baking soda and vinegar, can work. And so can bleach. You can also opt to use antifungal sprays and chemicals that are specifically designed to kill mold.

No, mold cannot be completely removed from a house. This is because mold spores exist in the air naturally. This includes the outdoor environment. Therefore, for as long as there is air circulation in a house, and provided the windows and the doors are occasionally left open, there will always be mold in a house.


Professionals usually start the mold removal process by first inspecting the affected home or room. They document the evidence of mold attack by taking photographs and recording videos. Using the documented evidence, they develop a mold remediation plan.


The actual removal process usually starts with shielding the area that they have to work on. They normally do this by shutting doors, windows, and other openings. They then seal it off with polyethylene sheets.


This is usually followed by the removal of unwanted material from the area. The area is then misted to encourage dust to settle.
Thereafter, the professionals clean the surfaces. This may be by physically scraping the mold off or through vacuuming. They may then use cleaning agents to get rid of any dirt and mold stains.

Application and testing

After they are done, they apply a mold-killing solution. They usually leave the solution to work for a while before cleaning up. A post mold remediation test then takes place soon thereafter — within 48 hours.

Timothy Munene
Author: Timothy Munene - Timothy is a freelance writer and an online entrepreneur.