Evaporative Emissions Testing System

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Webber EMI manufactures a wide range of evaporative emissions testing systems in a variety of sizes, ranging from 10 cu-ft Micro SHEDs to full sized Vehicle SHEDs capable of testing HD construction vehicles. Starting with one of our standard configurations, a evaporative emissions testing system can be custom-built to our customer specifications with specific regard to size, window placement, access door type, and other performance or testing needs. All Webber EMI SHEDs incorporate a modular-systems design that allows the basic Fixed Volume / Fixed Temperature (FV/FT) enclosure to be upgraded to full Variable Volume / Variable Temperature (VV/VT) enclosure — even years later — on-site, and after installation.

FV/FT Vehicle SHED

The Webber EMI Model 101 Vehicle SHED has been an industry standard for decades. It incorporates an entry-level Fixed-Volume / Fixed-Temperature (FV/FT) test system design that, even years later, can be upgraded into a full Variable-Volume / Variable-Temperature (VV/VT) SHED evaporative emissions testing system. It is available in several standard sizes suitable for testing complete vehicles, motorcycles, small tractors, off-road vehicles, lawn mowers, small machines and hand-held equipment.


VV/VT Vehicle SHED

The Webber EMI Model 101 Vehicle SHED is also available as a Variable Volume / Variable Temperature (VV/VT) SHED. This SHED is designed to support a full range of test protocols and temperature profiles between 45 F and 120 F. Using the Webber EMI moveable roof system, absolute SHED volume is automatically controlled to maintain zero-differential pressure between the SHED interior and ambient laboratory conditions. It is designed for testing large equipment such as cars, trucks, tractors and other large machinery.



The Webber EMI Model 102 Mini- SHED is designed to facilitate testing applications which require a medium sized enclosure with the ability to resolve a very low emission concentration. This test system incorporates all of the features associated with our ‘full vehicle’ SHED systems but, the enclosure has been re-sized to a smaller foot print. This helps to improve emission detections and is suitable for testing small equipment such as ATV’s, lawn mowers, and other objects equivalent in size.


(Photo courtesy of the California Air Resources Board)

Micro SHED

The Webber EMI Model 103 Micro SHED test system is designed specifically for Ultra-Low (ULEV) and Zero (ZEV) Emission level evaporative testing. While incorporating most of the features associated with our full vehicle SHED systems, the Micro-SHED test system has been re-sized to facilitate automated evaporative testing of smaller complete utility products, sub-systems and discrete components such as fuel tanks, valves, hoses, and canisters. With the ability to detect HC emission changes as low as 0.1 ppm/ mass emissions as low as 0.10mg.


Running Loss SHED

The Webber EMI Running Loss SHED is a modified version of our full-sized Vehicle SHED. This extra long SHED, equipped with special air handling equipment, a proportional speed fan, vehicle combustion makeup air, and an auxiliary personnel door, is combined with a centrally located dynamometer to accept both front- and rear-wheel drive vehicles. In addition to full exhaust emissions testing capability, this SHED supports all applicable diurnal evaporative emissions test protocols.


(Photo courtesy of the California Air Resources Board)

On-Board Refueling & Vapor Recovery

Webber EMI can provide On-Board Refueling / Vapor Recovery (OR/VR) capability to any of our SHEDs either new or existing with on-site installation. Locations, height and amount of ports can be placed in a variety of places to best suite the end user. Using several different methods, vehicles or other fuel-dependent machines can be re-fueled while the SHED is sealed.


All Webber EMI SHEDs are available as full VV/VT enclosures, or as FV/FT enclosures that can later be upgraded to VV/VT capability.

SHED Systems

Micro SHED (10-100 cu ft) Mini SHED (100-1000 cu ft) Vehicle SHED (1000-2000 cu ft)
Fixed Volume / Fixed Temperature (FV / FT)
Standard Volume 64 cu ft 324 cu ft 1680 cu ft
ID (W x H x L) 4’x4’x4′ 6’x6’x9′ 10’x8’x21′
Temperature 72° F 72° F 72° F
Vehicle Door Side-hinge Side-hinge Top-hinge
Heat & Cool Unit Self contained Self contained Self contained
Purge System Single poppet valve Single poppet valves Single poppet valve


(Available at time of manufacture only.)

Volume Custom volume Custom length Custom length
Vehicle Door Guillotine or Top/Bottom-hinge Guillotine or Top/Bottom-hinge Guillotine
Personnel Door Side-hinge
Heating & Cooling Unit Facility dependent Facility dependent Facility dependent
Purge System Dual poppet valves


(Available both at manufacture and after installation.)

Variable Volume / Variable Temperature (VV / VT)

Volume System Moveable Roof, Mass-Flow Balance, or Bag system Moveable Roof, Mass-Flow Balance, or Bag system Moveable Roof, Mass-Flow Balance, or Bag system
Standard Temp Range 65° F – 105° F 65° F – 105° F 65° F – 105° F
Extended Temp Range 45° F – 145° F 45° F – 145° F 45° F – 145° F

Fuel Tank Temperature Management System (FTTMS)

Heater Outlets 1 Up to 3 Up to 3
Heater Power 2kW / outlet 2kW / outlet 2kW / outlet
Auxiliary Outlets 1 Up to 2 Up to 2
Auxiliary Power 20A / outlet 20A / outlet 20A / outlet

Onboard Re-fueling / Vapor-Recovery (OR / VR)

Nozzle Access Quick Disconnects Glove & Nozzle Boots or Quick Disconnects Glove & Nozzle Boots or Quick Disconnects

If you need additional equipment not shown here, contact us with your requirements.

Why choose a Webber EMI SHED?

Download a brochure on Evaporative Emissions Testing System: