Getting cars clean in varying winter conditions is challenging. Many parties blame this on road salting. Why, and is there any basis in the claim?
Tekno-Forest Ltd’s test team clarified the matter in an article published in Bensiiniuutiset in 2018.
IS ROAD SALTING THE CAUSE OF WINTER WASHING CHALLENGES?
In the study, washing results were examined in car washes at three different stations of the same service station chain. Behind the car’s front tire, near the sill board, six painted and clean test plates were attached. After that, the car was driven on the newly salted Helsinki-Tampere highway until a smooth and sufficiently thick layer of dirt accumulated on the surface of the plates. After removing the plates, three of them were left outside for protection. The other three were moved indoors for two days to dry. In this way, plates coated with both fresh dirt and hardened dirt were obtained for the test. In addition to these test plates, an asphalt bitumen film was applied to three clean test plates in the laboratory. The film was allowed to dry on the plate surface for two days. After that, a set of three plates (fresh, hardened and bitumen-coated plate) was attached to the side skirt of the car and the car was driven for a test wash at all three stations. In each washing machine, the most expensive “Brilliant Wash” program was selected. The washing program included a separately applied sill solvent. This ensured that the test plates were washed using a strong pre-soak.
Test washes were performed on the same day, within three hours. The outside temperature was -1 C.
The test plates were photographed just before putting them in the washing machine and immediately after the washing program.
What came out in the wash?
The salt stain disappeared almost completely from the surface of the test plates in all three washes. Some dark spots (bitumen pots) remained on the test plates of the first and third test stations. The clearest difference was in the washing of the brown bituminous film. At the second test station, the disc was mostly cleaned, whereas at the first station, only a slight cleaning was observed. At the third station, the bitumen film had remained almost completely on the surface of the board. Even with hardened salt dirt, the best washing result was achieved at the second station. At stations one and three, the salt dirt had not been cleaned from the surface of the test plate at all.
The right kind of liquid detergent for challenging conditions
The test results confirm that there are large quality variations in the washing results of different stations of the same chain. An acceptable washing result was achieved at station two, while the poor result of stations one and three points to the use of an unsuitable detergent system for winter conditions.
The quality deviations of washing programs of the same name are explained by the fact that washing machines and chemicals supplied by different manufacturers are used within the same service station or washing chain.
The weak washing results of stations one and three are partly explained by the lack of winter adjustments of the washing programs or the fact that the pre-soak concentrations in the program were left too low.
It is also possible that the “euro/washing” agreement applied in the industry is the reason for the general collapse of washing quality in winter conditions. Fixed-price contracts independent of the washing program do not encourage chemical suppliers to adjust detergent concentrations to the level required by the conditions, as this increases costs in the same proportion. This, in turn, increases the risk that customers’ dissatisfaction with the station’s washing results will increase, which in turn leads to weak washing sales development and an increase in demand for hand washing services. To prevent this from happening, you need a pre-soak solvent of the right type and targeted at the right place, with a sufficient concentration and duration of action, for the most challenging conditions of the winter season.
