A particulate monitor, also known as a particle monitor, is an instrument used to measure the concentration of airborne particles in the atmosphere. These monitors are typically used to monitor indoor air quality, workplace safety, and outdoor air pollution levels.

There are several types of particulate monitors available, but most use either light scattering or filter-based techniques to measure particle concentrations. Light scattering monitors use a laser or LED light to detect particles in the air, while filter-based monitors collect particles on a filter and then weigh the filter to determine the particle concentration.

There are several types of particle monitors, including:
1. Optical Particle Counters: These use laser light to detect particles in the air and classify them by size.
2. Scanning Mobility Particle Sizers: These instruments use an electrical charge to classify particles based on their size.
3. Condensation Particle Counters: These use a condensation nucleus counter to detect and measure particles in the air.
4. Beta Attenuation Monitors: These measure the concentration of particles in the air by measuring the attenuation of beta radiation as it passes through a filter.
5. DustTrak Monitors: These use a light-scattering technique to measure the concentration of particulate matter in the air.
6. Filter-Based Monitors: These collect particles on a filter and then measure the weight of the filter to determine the concentration of particles in the air.
7. Real-Time Aerosol Monitors: These measure particle concentrations in real-time using a variety of techniques, such as light scattering, laser diffraction, or particle image velocimetry.

Different types of particle monitors have different advantages and disadvantages, depending on their intended use, the size range of particles they can detect, their accuracy, and their cost.

Particulate monitors are important because airborne particles can have harmful effects on human health and the environment. For example, particulate matter (PM) is a major component of air pollution and has been linked to respiratory and cardiovascular problems. By monitoring particulate levels, researchers and policymakers can better understand the sources and impacts of air pollution and take action to mitigate its effects.