Today, gasoline at gas stations is the same in appearance, and you can only distinguish it by name, and pistols are marked in different shades. But in the days of the Soviet Union, the fuel itself was painted in certain colors. Moreover, such a fate befell not all brands, and this was done solely for security purposes. This is probably why they are already thinking of returning to this practice.
Many of those who lived in the USSR remember that since the sixties of the last century four types of gasoline could be found at gas stations: A-66, A-72, A-76 and AI-93. Its cost ranged from 60 to 95 kopecks. The brands of fuel were distinguished by the octane number, which was determined either by an automobile (or motor), or by a research method - hence the differences in the abbreviations of different brands of gasoline.
However, there was another concern for those who produced the much-needed substance for cars - in order to reduce the percentage of detonation and increase the octane number, the Soviet Union used the same method as in other countries at that time. We are talking about the addition of tetraethyl lead, a highly effective additive that made the fuel leaded. Only one Soviet-made gasoline - A-72 - did not have this additive.
And it was leaded gasoline that had to be painted in accordance with GOST. This was done for two purposes: firstly, so motorists could easily distinguish the brand of fuel. And secondly, leaded gasoline was simply dangerous to human health, therefore, today it is prohibited for sale. Moreover, according to the Novate.ru editors, such gasoline, if poured into a modern car, will do more harm than good.
But in the USSR it was used actively, since then there simply was no alternative. And the shades of the dye depended on the brand of gasoline: for example, A-66 was painted orange, A-72 - green, AI-93 was blue. And only unleaded A-72 remained natural. Over time, the color gradation changed: high-octane AI-98 fuel, which was supplied only to enterprises, began to be colored blue. And the A-72 brand at some point became leaded and got a pink tint.
By the way, the dyes did not affect the properties of the fuel in any way, which is probably why the practice of dyeing gasoline was preserved in a number of European countries: for example, in England, Germany or France. There, this method is used not only as a marking, but also in order to avoid the purchase of counterfeit products. In the domestic open spaces, they are also thinking of returning this color gradation, but when exactly this will happen is still difficult to say.
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