Portable Emissions Measurement System

A Portable Emissions Measurement System (PEMS) is essentially a lightweight ‘laboratory’ that is used to test and/or assess mobile source emissions (i.e. cars, trucks, buses, construction equipment, generators, trains, cranes, etc.) for the purposes of compliance, regulation, or decision-making. Governmental entities like the United States Environmental Protection Agency (USEPA), the European Union, as various states and private sector entities have begun to utilize PEMS in order to reduce both the costs and time of mobile emissions decisions. Various state, federal, and international agencies began referring to this shorthand term in early 2000, and the nickname became part of industry parlance.

Since the mid-1800’s, Dynamometers (or "dyno" for short) has been used to measure torque and rotational speed (rpm) from which power produced by an engine, motor or other rotating prime mover can then be calculated. A chassis dynamometer measures power from the engine through the wheels. The vehicle is parked on rollers which the car then turns and the output is measured. These dynos can be fixed or portable. Because of frictional and mechanical losses in the various drivetrain components, the measured horsepower is generally 15-20 percent less than the brake horsepower measured at the crankshaft or flywheel on an engine dynamometer . Historically though, dynamometer emission tests are very expensive, and have usually involved removing fleet vehicles from service for a long period of time. Also, the data derived from such testing is not representative of “real world” driving conditions, and cannot be deemed as quantifiable, especially due to the relatively low amount of repeatable tests at such a facility.

Portable systems began to be developed in the late 1990’s in order to better identify actual in-use performance of vehicles. PEMS are designed to measure emissions during the actual use of an internal-combustion engine vehicle or equipment in its regular daily operation, in a manner similar to operation on a chassis Dynamometer. This methodology and approach has been recognized by the USEPA

Many governmental entities (such as the USEPA and the United Nations Framework Convention on Climate Change or UNFCCC) have identified target mobile-source pollutants in various mobile standards as CO2, NOx, Particulate Matter (PM), Carbon Monoxide (CO), Hydrocarbons(HC), to ensure that emissions standards are being met. Further, these governing bodies have begun adopting in-use testing program for non-road diesel engines, as well as other types of internal combustion engines, and are requiring the use of PEMS testing. It is important to delineate the various classifications of the latest ‘transferable’ emissions testing equipment from PEMS equipment, in order to best understand the desire of portability in field-testing of emissions.


Animal Print Rug
in wall aquarium
Wallets And Purses
Cummins Engine Parts
nut bolt washer
Men's Outdoor Jacket
microscope cover glass
Boat trailer hardware
non-stick dutch oven
industrial coffee machine
vibration exercise machines
folding silk screen
jet fuel a1
latex bed sheets
automotive water pump
portable handsfree kit
diamond emerald necklace
Welding And Soldering
musical water globe
motorcycle wheel weights
Mini LED Torch
baby knee socks
av cables rca
ladies leather sandals
Plastic Pill Boxes