Exhibitor Products


Quantifit from OHD

Shawcity Limited Stand: 4/J110

What technology does it use?

Quantifit uses controlled negative pressure (CNP) technology. It uses only air as the challenge agent to directly measure the leak rate from an RPD, as opposed to traditional methods of quantitative ambient aerosol sampling, where the number of particles both inside as well as outside the mask are counted.

How does it work?

During a fit test, the respirator inlets are capped with test adapters, and the inhalation valves are propped open or removed from the mask during testing only. With the test subject holding their breath for no more than ten seconds, the Quantifit then establishes and maintains a slight vacuum, or controlled negative pressure, inside the mask.

Since the respirator inlets are sealed, all sources of leakage into the mask are through the face-to-facepiece seal or due to integrity issues. The volume of air drawn out of the mask by the Quantifit during this short period of time is equal to the leak rate into the mask through the face-to-facepiece seal.

What is Quantifit’s fit factor?

In the UK and Ireland the fit factor number is most commonly associated with the ambient aerosol particle counting method. Quantifit adheres to the same HSE fit factors of 100 for a half mask and 2,000 foor a full face mask.

International Standard ISO 16975-3 (First edition 2017-09)*

Respiratory protective devices – Selection, use and maintenance – Part 3: Fit-testing procedures.

Is it compliant with current fit testing legislation?

In the UK, CNP fit testing is fully referenced as a method of fit testing in the HSE document INDG479. Shawcity has been working closely with the BSIF and the Fit2Fit RPE Fit Test Providers Accreditation Scheme who have also published a separate Fit2Fit Companion Guide for CNP testing. The Shawcity team has been trained by the manufacturer OHD to deliver full competence and user training to Quantifit customers. Other Fit2Fit scheme members also deliver CNP fit testing and training.

What do I need to perform a fit test with Quantifit?

Quantifit is a standalone unit which only needs a power supply and air to be able to perform a fit test. With no requirements such as particle generation through salt fog, burning candles or incense it is the simplest form of fit testing available.

Where can I use Quantifit?

Just about anywhere, as long as there is a power source. Quantifit is a totally portable lightweight unit, weighing less than 3.5kg. It requires no special air quality conditions so it can used anywhere in the workplace, both indoors or outdoors and in clean or dirty air. This flexibility offers a huge advantage in terms of convenience as it allows the fit test team to take kit out to operatives in the field, instead of summoning the workforce to report to a specific location within a controlled, suitably-contaminated environment.

How do I store and retrieve fit test data?

Quantifit can store up to 500 separate fit test measurements on its own in-built memory, which will be retained on the unit for two years, even without power. Functionality includes reporting options for calibration and reporting, while individual fit test cards and logs and can be printed to a designated HP printer. Or data can be uploaded to FitTrack Gold software on a PC via USB for full analysis. Operation on-site with a computer offers unlimited data records, full functionality with any Windows-compatible printer and report export and storage. Users can also update/create individual personnel records on the database.  

What about servicing, maintenance and calibration?

Shawcity is the authorised service centre for Quantifit in the UK and Ireland. We can arrange collection and delivery and even supply a hire unit while yours is with us for servicing, calibration or repair. Quantifit is an exceptionally easy device to use and maintain as there are no consumables, chemicals, filters or sensors to get contaminated or need replacing. A weekly maintenance and cleaning schedule is all that is necessary, as well as a one-minute daily calibration.

Where is it made?

Quantifit is manufactured in the Unites States by OHD, who are part of the Schauenburg International group of 40 companies, with headquarters in Germany.

Where can I buy or hire it or request a demonstration?

Quantifit is exclusively available from Shawcity in the UK and Ireland. Contact our team to arrange a free demonstration or for any further information.

Why Try Quantifit?

Quantifit offers customers the following further benefits:

  • Air is the highest level of challenge agent. If air can get into the mask then so can vapours, gases and particles.
  • No consumables! Unlike traditional ambient aerosol particle counting methods, Quantifit does not require alcohol wicks or probes, or burning incense or candles to create particles, reducing the ongoing cost of ownership and contamination issues.
  • Unlike ambient aerosol particle counting, users can be tested with Quantifit directly after smoking as the residual particles do not interfere with the fit test.
  • Free competence and user training delivered by Shawcity, as well as free ongoing technical support and aftercare for the lifetime of the instrument.

Quantifit is a quantitative system designed to fit test tight-fitting respiratory protective devices (RPDs) worn on the face. Quantifit and its predecessor, the FitTester 3000, have been sold for over 20 years and are used by Fire Departments and other Emergency Responders; Law Enforcement agencies including the FBI, CIA, NYPD; industrial hygienist teams including 3M, Boeing and Disney; oil and gas companies including BP, Conoco and Exxon.

Contact Exhibitor


  • aerosol
  • air
  • ambient
  • calibration
  • cnp
  • controlled
  • fit
  • full
  • including
  • mask
  • ohd
  • particle
  • particles
  • quantifit
  • shawcity
  • test
  • testing
  • uk
  • unit
  • use
  • well


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