Information on SHED Test

SHED is an acronym for Sealed Housing Evaporative Determination. There three main types of SHED systems viz., Micro SHED (approx. capacity 48 cu ft), Mini SHED (approx. capacity 288 cu ft), and Vehicle SHED (approx. capacity 1680 cu ft).

Generally, SHED test machines are available in following varieties:
Fixed Volume (FV) / Fixed Temperature (FT) Chambers
Variable Volume (VV) / Variable Temperature (VT) Chambers
Onboard Refueling (OR) / Vapor Recovery (VR) Chambers

However, equipment can be built by manufacturers with customized options.

Variable Temperature (VT) SHED Chambers are used for hydro-carbon emission tests in vehicle components carrying fuel or permeation tests in fuel tanks. The test chamber provides protected test space with analyzer, lighting, window, volume compensation device and a refueling lead-through plus flushing and safety equipment.

When hydrocarbon emissions are measured for conformance testing of a vehicle’s fuel and vapor handling systems, SHED procedure is used. Flame Ionization Detection (FID) techniques are used for these measurements.

There are test specifications recommended by various Standards Organizations like Bureau of Indian Standards (BIS), Economic Commission for Europe (ECE), Environmental Protection Agency (EPA) Japanese Stanards.

Prepared by
Krish
Jythra Engineering Services