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March / April / May 2016 : An unethical commercial practice

Written by Dubosc
Monday, 04 April 2016 22:50

Another “veteran’s story”, some 25 years old…Nevertheless, we are sure that some of our readers have known it. As for our younger readers, it may be a useful to inform them about an unfair commercial practice of that time.

This renowned supplier of PT materials and equipment, no longer in the non-destructive testing (NDT) business, marketed spray cans in a rather peculiar way.

Then chlorofluorocarbons (CFCs) were still allowed as propellant in spray cans. This propellant generally came as a blend of trichlorofluoromethane (CF 11) and dichlorodifluoromethane (CFC 12). However, times were changing because the French nuclear energy and the aerospace industries started to ban using chlorinated ingredients (including the propellants).

While many PT/MT manufacturers used CFCs as propellants in spray cans, we both supplied on the French market spray cans with a blend of butane and propane as propellant, the mass density of which is low compared to that of the CFCs blend: the CFC 11 mass density is about 1,490 kg/m3 and that of the liquefied CFC 12 is about 1,486 kg/m3.

With a claimed volume of 300 mL (in compliance with the then applicable regulation), our spray cans of penetrants or developers weighed circa 350 grammes. A competitor went to our customers, offering the same 300 mL spray cans that weighed more than 500 grammes. “Look, for the same price, you get far more product than in the spray cans of …… or ……”

Yes…the customer bought a heavier propellant, but the quantity of active product was the same, exactly. Further, the truth is that the products from this supplier were far from the quality assured by the two main competitors.

Another supplier, also no longer active in the non-destructive testing (NDT) business, marketed its PT spray cans by creating a subtle confusion in his customers’ mind, between net and total volumes of the spray cans, when giving them his price list. For instance, the spray cans containing a liquefied propellant and 300 mL of product, as per the regulation, must have a 405 mL capacity. Therefore, write “405 mL”, instead of “300 mL” in the price list…and it was done!

Therefore, users shall always be careful, when a product comes with too many “advantages” by comparison with renowned equivalents. Ask questions; ask people who are more technically experienced.

For further information, you may also read one of our papers dealing with propellants for spray cans (1).


(1)Pierre CHEMIN and Patrick DUBOSC, Propellents for PT/MT spray cans, March and April 2009.



Last Updated ( Tuesday, 05 April 2016 23:02 )