Sand Attack will lower the opponent's Accuracy by 1 step (termed BTLs in the Gameboy description) on the standard Accuracy scale.
Sand Attack will always fail if it has already been used 6 times on the same pokemon, without a move that raises Accuracy being used by or against the pokemon affected by Sand Attack. This is due to the fact that a stat may only be lowered by a maximum of 6 steps, until it is reset by the use of Haze or the pokemon is switched out normally. The maximum is the limit of how many decreases can be applied to a stat. If another move decreases the Accuracy stat of the pokemon that Sand Attack is used against, the number of steps that it decreases the Accuracy stat by will count toward the 6 step limit, and reduce the number of times that Sand Attack can be used appropriately.
As a non-damaging Ground attack, a Flying type pokemon's immunity to Ground attacks does not protect from the effects of Sand Attack.
Sand Attack is affected by Brightpowder when the opposing pokémon is equipped with it.