Minimum sample size needed to assume Normality

The pdf here from here is available from here if the link is broken.

The below extract taken from the above link suggests that 30 observations is sufficient to make the assumption of a Normal distribution tenable.

“In general, it is said that Central Limit Theorem “kicks in” at an N of about 30. In other words, as long as the sample is based on 30 or mote observations, the sampling distribution of the mean can be safely assumed to be normal”