The ITTF rules and what happens in practice
Section 3.5 introduced the grey area of boosting in the context of the general rules: a broad rule and an enforcement instrument that does not fully cover it. It is worth dwelling here on the details of that gap, because it determines what a player meets on arriving at a competition.
The ITTF rules establish, in general terms, that the covering of the bat must consist exclusively of the materials it was manufactured with. Treating the rubber physically or chemically after production is not permitted. The rule is categorical and draws no distinction between substances: any post-manufacture alteration breaches it. Read that way, boosting is illegal without qualification.
The problem lies in detection. The instrument the ITTF deployed after the 2008 ban — the VOC tester described in 3.6 — measures the presence of volatile organic compounds on the surface of the rubber. It was designed for speed glue, whose base was precisely those compounds. Modern boosters, by contrast, are formulated with low-volatility oils that do not trigger the sensor, or trigger it only during the first hours after application. Where the player applies the product far enough in advance — typically several days — the rubber passes the check without incident. The rules prohibit; the tester does not detect. That asymmetry is the heart of the grey area.
In international practice the situation is an open secret. At high-level tournaments organised by the ITTF, the check is applied systematically before matches: the umpire passes the tester over both rubbers and verifies that the covering does not exceed 4.0 mm in total thickness — a point connecting with what was explained in 3.2, because a treated sponge swells and can go over the limit. What the tester does not capture, however, is not pursued. There are no laboratory analyses, no surprise checks out of competition, no sanctions for possession of the product. The system confines itself to what the instrument can measure at the moment of inspection.
At national and club level, enforcement is more uneven still. Many national federations do not have testers at every tournament, or use them only in the closing rounds. In ordinary club league play, equipment inspection is infrequent or non-existent. The result is that boost circulates as a matter of course in most national circuits, and the real probability of being sanctioned for using it is low outside top-level international events.
Why has the ITTF not closed the gap? The answer has several layers. Developing a tester capable of detecting non-volatile oils with the same speed and reliability as the current VOC detector is technically complex. Effectively prohibiting a practice millions of players carry out — especially in the Chinese tradition, whose playing logic presupposes it, as 14.5 will show — raises a problem of mass enforcement. And tightening the controls without offering a viable alternative to rubbers that need treatment in order to work as designed would create a competitive distortion that would be hard to manage. The ITTF has opted, de facto, for tacit tolerance within the limits the current tester imposes.
A player wanting to compete in the certainty of meeting the letter of the rules has one clear option: apply no treatment at all. Anyone choosing to operate in the grey area should know that the risk of sanction depends on the level of the competition, the product used and the time elapsed since application. The specific oils and their characteristics are dealt with in 14.6; the risks of damage to the rubber and to health, in 14.7.