Clean shop = clean air

Starting and idling the engine in an enclosed area, such as an auto repair shop, causes harmful exhaust fumes to build up. If we add that this operation is repeated on average about a dozen times a day, then the scale of the problem turns out to be too noticeable. To ensure safe working conditions, exhaust gases are removed directly from the vehicle's exhaust pipe using so-called exhaust gas extractors. Depending on the size of the workshop or diagnostic station, different options for the removal of combustion products of the fuel-air mixture are installed.

Belts - but what?

First, let's get acquainted with the principle of operation of hoods. In a nutshell, it consists in creating a vacuum at the outlet of the exhaust gases from the car's exhaust pipe. The latter are removed outside the facility using a flexible exhaust pipe. Depending on the size of the workshop, various design solutions for exhaust gas systems are used. In small, with one or two workplaces, single or double hinged or drum lashing, as well as the so-called. portable (mobile) and floor systems. On the other hand, in multi-station workshops, mobile extractors are most often installed to ensure that exhaust gases are properly removed from a moving vehicle before it leaves the workshop building.

One or two

Single or double exhaust extractors are used in small car workshops. They consist of a fan and a flexible duct (tubes) with nozzles attached to the vehicle's exhaust pipe. In the simplest solutions, cables are hung from walls or stretched with balancers. Thanks to the latter, after disconnecting the nozzle from the exhaust pipe of the car, the flexible pipeline itself returns to its original state. Another solution is the so-called drum extraction. Its name comes from a flexible hose wound on a special rotating drum. The principle of operation is the same as for single and double hoods. However, the flexible ventilation hose is wound on a drum: using a spring drive or using an electric motor (controlled from a remote control in more complex versions). The drum extractor is usually mounted to the ceiling or wall of the workshop.

Mobile and portable

A mobile haul, also known as a rail haul, uses a special trolley that moves along a rail to carry exhaust gases. The latter is mounted both longitudinally in relation to the inspection channels, and transversely behind the cars. The advantage of this solution is the ability to connect a flexible pipe to the exhaust pipe of a moving, not just a stationary car. The scraper is automatically switched off after the test vehicle leaves the gate of the garage or service station. Another advantage of the mobile dust extractor is the possibility of connecting several flexible hoses to it. Depending on their number, it can work with one or more fans. The most mobile version of the hood is a portable (adjustable) system. In this solution, the fan is placed on a special frame that moves on wheels. Unlike the systems described above, the portable version does not have a nozzle in the exhaust pipe. Instead, there is a special connector that is located as close as possible to the outlet. The latter are brought out of the workshop with the help of a flexible pipeline.

With channel in the floor

And finally, the last type of exhaust outlet is the so-called floor system. As the name implies, the products of the combustion process of the air-fuel mixture are diverted to an installation located under the floor of the workshop. In the case of points with a small number of workplaces, the optimal solution is its variant with a flexible cable laid in a special channel in the floor. The advantage of this solution is the permanent presence of the cable, which at the same time does not take up space in situations where it is not needed. The main disadvantage is the limitation of the diameter of the hose itself and the size of the suction pipe. Another option for a floor system is a system with flexible piping connected to a dedicated floor socket. The most important advantage is its mobility: an employee can connect it to a socket where the vehicle is being inspected. In addition, in this version of the floor system, there are no restrictions on the diameter and size of the suction pipe in a solution hidden in the floor.