A good, airtight respirator fit is as crucial as providing protective equipment to workers who are constantly exposed to hazardous airborne particles. Without the proper seal, the respirator would fail to protect workers against harmful gases and contaminants.
This is why a respirator fit test is crucial and must be part of your company’s standard practices in upholding safer spaces for your workers. Some might already know this, including you, and your dilemma now is probably selecting the fit-testing method that best suits your business.
In this article, have an in-depth look at the difference between the two most common fit testing methods: quantitative fit test and qualitative fit test.
What is Quantitative Fit Test?
A quantitative fit test (QNFT) is a more technical approach. It uses machines like PortaCount to measure and quantify possible leakage.
But how does this work? A QNFT instrument uses the Ambient Aerosol CNC to calculate the number of particles surrounding the mask. This data will then be used to calculate the fit factor, a unit of measurement used to identify whether respirators fit adequately.
QNFT is preferred in healthcare, chemical plants, and pharma for its unparalleled accuracy.
What is Qualitative Fit Test?
While QNFT offers numerical and objective data, qualitative fit testing is a simple pass-or-fail method highly dependent on the wearers’ senses. This test lets the respirator user wear the equipment and expose it to various agents, like saccharin, Bittrex, or isoamyl acetate.
The solutions trigger the wearer’s sensory reaction, and they must use their taste, smell, or irritation to detect leaks.
With QFT’s approach, the results indeed rely on the subject’s truthful reporting of their experience. This test is subjective and typically used for disposable and half-face respirators. It’s also common in construction and general manufacturing industries.
Key Differences Between Quantitative and Qualitative Fit Tests
Testing Methods
The most glaring difference between quantitative and qualitative fit tests is their testing approach. QNFT is strictly objective, using numerical data to assess the respirator’s seal.
Meanwhile, a qualitative fit test is subjective and relies only on your ability to taste or smell testing agents. Your sensory input is the sole basis of the test.
Equipment Used
To provide accurate results, QNFT requires specialised, complex equipment like fit test machines. It’s different for QFT, though, as it relies on simple materials like testing agents and nebulisers. Hence making it more affordable and accessible.
Accuracy and Precision
In this topic, it’s clear that QNFT provides better accuracy and reliability as it eliminates subjectivity and bias. However, this does not mean that the qualitative fit test is unreliable, it’s just the possibility of producing variable results is higher compared to QNFT.
Pros and Cons of Quantitative and Qualitative Fit Tests
Advantages of Qualitative Fit Testing
- Cost-Effective: If you’re on a limited budget, a qualitative fit test is more economical as it’s cheaper and more accessible.
- Ease of Use: Since QFT requires no complex equipment and is more straightforward, fit tests can be conducted quickly.
- Ideal for Smaller Operations: The qualitative fit test is ideal for workplaces like construction or manufacturing, where disposable masks are common and acceptable.
Advantages of Quantitative Fit Testing
- Precision: The QNFT is preferred for high-risk environments requiring high precision. This test can give you an accurate assessment to help minimise risks in the workplace.
- Reliability: Little to no human intervention occurs during the test, so you can expect data and numbers-driven results.
- Versatility: This type of test can be used for different respirator types, including reusable respirators.
Limitations of Each Test
- Qualitative Fit Test: Results are subjective, which can compromise the results and make them less reliable.
- Quantitative Fit Test: High accuracy means high cost, so be prepared to cash out a large sum, which you’ll use for equipment costs and technical experts’ fees.
Choosing the Right Fit Test for Your Needs
Factors to Consider
The most crucial factor you need to consider is your workplace’s needs. You should also check the risk level, budget, and respirator types.
If you’re in a high-risk environment, you need QNFT’s precision. This means that you must also prepare a budget for this since QNFT is not cheap. However, a qualitative fit test can already suffice if your respirator use is only small-scale.
Industry Standards and Regulations
The Occupational Safety and Health Administration (OSHA) has set standards regarding the use of QFT and QNFT. As businesses in hazardous fields, it’s essential that you comply with these guidelines and ensure that your chosen method is aligned with their rules to avoid penalties and legal repercussions.
Making the Right Choice for Workplace Safety
Regardless of the methods, fit testing is crucial in maintaining workplace safety. Though one method can fit your needs better, one factor you shouldn’t miss to consider is the people who’ll be the wearers of respirators in the workplace.
If you’re still unsure of the method that can work for you, consult a trusted expert like Lim Kim Hai Electric.
We are 3M certified and provide many products or services to meet your safety needs, including QFT and QNFT. In addition to fit testing services, we are a leading safety equipment supplier in Singapore, offering safety solutions and accessories for businesses in the manufacturing, aviation, and oil and gas industries, among others.
