Jargon Buster


Our helpful guide to navigating some of the terms and jargon most frequently encountered in the particulates space.  

Remember, we offer a free particulates report and risk-assessment with our vastly experienced Particulates Director for anyone who needs a more in-depth analysis of their own particulates issue. Free Dust Assessment Here 


Measurements of Particulate Matter






The unit of measurement generally used to describe the size of an individual particle. 1µm 

or micrometre/micron = 1 millionth of a metre. A human hair is typically around 60µm diameter. 










Particulates, or more specifically Particulate Matter (PM) - a mix of solid particles and liquid droplets suspended in air. PM10 refers to all particles of 10µm and below in a sample.  


PM2.5 particles are sometimes referred to as 'fine particles', and PM2.5–10 as 'coarse particles’. Fine particles can penetrate deep into the lungs. 











Short for nanometre. These are particulate sizes smaller than 1µm. So, the Air XD’s ability to detect a range of particulate sizes from 380nm means it can detect particles sized around a third of 1µm. 










ug/m³ or mg/m³ 

This measurement refers to particle density or the amount of particulate matter present in a given amount of cubic air. It’s the measurement most frequently referred to in legislation for respirable content. Typically, respirable dust should not exceed 4mg/m3 - equivalent to 4 teaspoons of flour spread over an entire soccer field up to a height of 1m! 










A measurement of density of particles expressed in mass/volume. The greater the density of the particle the higher the grams per millilitre.  








Technologies Used for Particle Detection 


TEOM:Tapered Element Oscillating Microbalance 

A continuous particulate monitoring system, using weight and oscillation to determine the amount of particulate matter present. The more dust present, the slower the oscillation 

 TEOM technology is limited in accuracy and requires high levels of regular maintenance to remain functional. 



OPC:Optical Particle Counters 

A light source projected onto particulates creating a light scatter effect which is measured by a receiver 

Tends to have low accuracy and limited detection range of particulates sizes. 

More advanced modern OPC-based instruments such as the Air XD deploy a higher intensity beam and multiple detectors determine full spectrum, real-time presence of particulates as high accuracy levels. 




Very similar to an OPC, but based on the absorption and scattering of light. As the intensity of the transmitted light decreases the more particulates are present. 

This technology has very low accuracy and measurement range and requires high levels of regular maintenance. 




Based on monitoring the changes in light wavelength before and after interacting with particulates. Changes in wavelength indicate the presence of particulate concentrations. The light output is converted into an electrical signal to give a reading.  

This technology has very low accuracy and measurement range and requires high levels of regular maintenance. 



Some terms we use in our literature 



Specific to our particulate monitoring range, the chamber through which particulates pass is completely free of obstacles that might lead to the build-up of dust that can compromise the accuracy of the unit.  



The area through which the laser-beam interacts with particulates. The wider a scatter-zone, the more information is collected by the light-scatter about particulate size, density and volume.  



We use “full-spectrum” to refer to the range of inhalable particulates from 0.35µm to 40µm that can be simultaneously measured by the Air XD 


Dust suppression 

The prevention or reduction of dust dispersion into the air, for example by water or foam sprays. This is not the act of taking dust out of the environment, but making it manageable and no-longer airborne, with a view to making it no longer respirable. 


Dust extraction 

The removal of airborne dust particulates, for example through fan extraction. 


‘Respirable’ particulates  

Particulates that can be inhaled. These are some of the most dangerous types of particulate, including crystalline silica, for example. Typically, particulates 4.25µm> are respirable. 



Diseases and Their Causes 


Crystalline silica 

A basic component of soil, sand, and granite, silicate minerals make up over 90% of the earth’s crust. When processed these minerals can produce crystalline silica, a shardy, irregular particulate which can cause diseases including silicosis, lung cancer, chronic obstructive pulmonary disease (COPD), and kidney disease. 

For more information, visit: https://www.hse.gov.uk/aboutus/occupational-disease/cancer/silica.htm 



A scarring disease of the lungs caused by inhaling fine particles of crystalline silica dust. Silica dust particles can trigger an inflammatory reaction that leads to the formation of lung nodules and scars. These changes can lead to a permanent loss of lung function. 

For more information, visit: https://www.nhs.uk/conditions/silicosis/ 



A chronic lung disease caused by inhaling asbestos fibres. Prolonged exposure to these fibres can cause permanent lung tissue scarring and shortness of breath. Asbestosis symptoms usually don't appear until many years after continued exposure. 

For more information, visit: https://www.nhs.uk/conditions/asbestosis/ 



‘Chronic Obstructive Pulmonary Disease’. The name for a group of lung conditions that cause breathing difficulties. It includes Black Lung Disease, Emphysema (damage to the air sacs in the lungs) and Chronic Bronchitis (long-term inflammation of the airways). 

For more information, visit: https://www.nhs.uk/conditions/chronic-obstructive-pulmonary-disease-copd/ 



Regulatory Terms 



‘Control of Substances Hazardous to Health’ (UK, EU)  

 The law that requires employers to control substances that are hazardous to health. You can prevent or reduce workers exposure to hazardous substances by:  

  • finding out what the health hazards are; 
  • deciding how to prevent harm to health (risk assessment); 
  • providing control measures to reduce harm to health; 
  • making sure they are used; 
  • keeping all control measures in good working order; 
  • providing information, instruction and training for employees and others; 
  • providing monitoring and health surveillance in appropriate cases; 
  • planning for emergencies. 

 For more information, visit: https://www.hse.gov.uk/coshh/basics/index.htm 




‘Workplace Exposure Limits’ (UK) 

Guides those responsible for controlling exposure to hazardous substances at work (COSHH). 

For more information, visit: https://www.hse.gov.uk/coshh/basics/exposurelimits.htm 




Permissible Exposure Limits (US) 

The maximum amount or concentration of a chemical that a worker may be exposed to under OSHA regulations. 

For more information, visit: https://www.osha.gov/dsg/annotated-pels/ 




Exposure Control Limit / Occupational Exposure Limit (EU) 

The two legal frameworks that form an integral part of the EU's mechanism for protecting the health of workers in hazardous environments. 

For more information, visit: https://echa.europa.eu/oel 




Workplace Exposure Standards (Aus) 

Workplace exposure standards for airborne contaminants in Australia. 

For more information, visit: https://www.safeworkaustralia.gov.au/doc/workplace-exposure-standards-airborne-contaminants  




The Institution of Occupational Safety and Health (US) 

The Chartered body and largest membership organisation for safety and health professionals. 

For more information, visit: https://iosh.com/more/about-us/ 




Occupational Safety and Health Administration (US)  

A governing body created to ensure safe and healthful working conditions for working men and women by setting and enforcing standards and by providing training, outreach, education and assistance. 

For more information, visit: https://www.osha.gov/aboutosha 



OSH Act 1974 

Occupational Health and Safety Act (Victoria, Aus) 

The act seeks to protect the health, safety and welfare of employees and other people at work. It also aims to ensure that the health and safety of the public is not put at risk by work activities. 

For more information, visit: https://www.worksafe.vic.gov.au/occupational-health-and-safety-act-and-regulations 



WHS Act 2011 

Work Health and Safety Act (NSW, Aus) 

A 2011 act that provides a framework to protect the health, safety and welfare of all workers in businesses in New South Wales. Reviews are scheduled once every five years.  

For more information, visit: https://www.safework.nsw.gov.au/legal-obligations/employer-business-obligations/managing-hazards-and-risks