€ Professional rate on request with a KBIS.

The P4000-NG replaces the P4000 from November 2020

Particulate matter, also known as PM, is a complex mixture of extremely small particles and liquid droplets. Particulate pollution consists of a number of components, including acids (e.g. nitrates and sulfates), organic chemicals, metals, and soil particles or dust.

Particle pollution is said to be the cause of 65,000 premature deaths per year in France and of many diseases (asthma, allergies, respiratory and cardiovascular diseases, lung cancer). Pollution is the second most common cause of death in France, ahead of alcohol and road accidents. The increase in deaths could become more pronounced with the health crisis. Indeed, with Covid-19, the mortality rate is expected to increase by 80% in Europe in 2020 according to the WHO. A question arises today concerning air pollution in 2021.

Concerning PM, the coarser ones (above 2.5 micrometers) fall down quite quickly, their residence time in the air is about 1 day, while the finer ones can remain up to 1 week in suspension and travel thousands of kilometers. Once deposited, the particles can then be re-suspended by the wind or, in urban areas, by road traffic.


French Version

P4000NG-Product Sheet

P4000NG Installation Manual

P4000NG Settings

P4000NG Modbus protocol


Modbus Data Logger for PC

Detection principle

The P4000-NG probe uses laser diffraction technology (Light Scattering).

The principle is as follows: When a laser beam passes through clean air, the beam is invisible. When the beam is visible, it is because the beam is distorts on particles along its way. If one looks at the side beam, the more the beam is visible, the more important the particle density.

Such a particle sensor uses a near-infrared source (laser diode). The sensor is an avalanche diode photo with an amplifier. Infrared is used to avoid any interference with daylight.

The density of the dust is primarily dependent on the airflow. The orientation of the laser and sensor ensures that no dust is deposited on the optical components when the air source is turned off. (Note that a fan operated for a few seconds every minute controls the airflow needed for particle counting and size discrimination.) Each particle passing through the front of the laser beam diffracts a portion of the beam to the photodiode, and the airflow is constant, and the measured pulse width allows the particles to be sorted by size.A running average of the number of particles in the category is performed in 60 seconds. Although larger particles exist in the indoor environment (especially fabric fibers), they are not harmful to health, so particles larger than 10 microns are not counted. PM (Particle Matter) refers to the total weight of particles per volume of air. This is a remnant of the time when the available technology was unable to detect individual particles. For each particle size, a typical mass is assigned to express the result in a standardized unit, i.e. µg/m³. Modern monitoring equipment, such as the P4000-NG, counts individual particles in three size classes that correlate to PM10, PM2.5 and PM1. The assumption for the mass calculation is that the particles are spherical, which is not always the case.

Standard values

Particle size is directly related to their potential health hazard. Environmental organisms are concerned about particles that have a diameter of less than or equal to 10 microns because it is the particles that usually pass through the throat and nose and penetrate into the lungs. Once inhaled, these particles can affect the heart and lungs and cause serious health effects.

The particles are classified into four categories:

˃ PM 10, coarse inhalable particles such as those found near roads and dusty industries, they are less than 10 micrometers in diameter and include fine, very fine and ultrafine particles.

˃ PM 2.5, fine particles such as those contained in smoke and haze, are less than or equal to 2.5 micrometers in diameter. These particles can be emitted directly from sources such as forest fires, or they can be formed when gases, emitted from power plants, industries and automobiles react in the air. Diesel engines are the main source. Includes very fine and ultrafine particles.

˃ PM 1, very fine particles (the most dangerous to health) are less than or equal to 1 micrometer in diameter. They are virtually removed only by precipitation and have time to accumulate in the air. Includes ultra-fine particles.

˃ PM 0.1, ultrafine particles with a diameter of less than 0.1 micrometer, also called "nanoparticles" Their residence time is very short, on the order of minutes to hours.

PM 2.5 and PM1 may descend into the deepest (alveolar) part of the lungs when gas exchanges occur between air and blood. These are the most dangerous particles because the alveolar part of the lungs has no effective means of eliminating them and if the particles are soluble in water, they can pass through the blood flow within minutes. If they are not soluble in water, they remain in the alveolar part of the lungs for a long time. Soluble elements may be PAHs (polycyclic aromatic hydrocarbons) or benzene residues classified as carcinogenic.


  EUROP (2010)   WHO USA
Daily limit P50* 50µg/m³ (less than 35 times/year)   50µg/m³ 150µg/m³
Annual Limit 30µg/m³   20µg/m³ Cancelled in 2006
Annual Limit 25µg/m³ in 2010 ;
20µg/m³ in 2020
  10µg/m³ 15µg/m³
Daily limit P98*       35µg/m³
Daily limit P50*     25µg/m³  
    <strong>PM10 (<10µm)</strong>    
    <strong>PM2.5 (<2.5µm)</strong>    
* : The value must not exceed 50% (98%) of the time.


✓ RS485 Modbus digital output (or EnOcean or LoRa via optional module). See protocol document for details;

✓ Optional 0-10V module and PV GV dry contacts (custom 0-10V output or PI control configurable by screen tool)

✓ Remediation control configurable by screen tool (via Modbus, 0-10V and or EnOcean).

✓ PM1, PM2.5, and PM10 densities expressed in µg/m3 (and in quantity per m3 in Modbus);

✓ One measurement every minute for a 10-year life span;

✓ Optional LEDs module (3 colors), color change according to thresholds set via the screen tool ;

✓ 12 to 32V DC or 12 to 24V AC power supply;

✓ Compatible with the E4000-NG probe as a Modbus slave

✓ Addresses, type (RTU/ ASCII) and speed of Modbus selectable by screen tool


Maintenance free

Lifetime 10 years

Examples of fine particles

<i class=" fa fa-angle-up" aria-hidden="true" role="img"></i>