According to Habitable Planets for Man, Stephen H. Dole, 1964, Table 2 on page sixteen, the approximate upper limits of various gases given as partial pressure in millimeters of mercury (mmHg) are:
Helium 61,000 (?)
Neon 3,900 (?)
Carbon Dioxide 7
According to Dole on page 15 the upper limit for oxygen is about 400 millimeters of mercury (mmhg).
The atmospheric pressure is 1.42 atm.
One atmosphere pressure is defined as 760 millimeters of mercury, so 1.42 atmospheres is 1,079.2 millimeter of mercury, and each percent of a gas in the atmosphere of that planet would be equal to 10.792 millimeters of mercury (mmHg).
Nitrogen 62 % equals 669.1 mmHg - within limits.
Oxygen 21 % equals 226.6 mmHg - within limits.
Argon 15.5 % equals 167.2 mmHg - within limits.
Xenon 1 % equals 10.792 mmHg - within limits.
Neon 0.49 % equals 5.28808 mmHg - within limits.
So every atmospheric gas listed seems to be at a safe pressure level, according to the data available to Dole in the 1960s.
Some answers indicated the oxygen and Xenon levels would be too high. So you might want to find out if any recent research has changed the acceptable levels of those gases since 1964, and ask the answerers what evidence they have for their statements.
Since the planet is supposed to be naturally habitable, it has to have liquid surface water in some locations at some times. And that means there will be some water vapor in the atmosphere. According to Dole in Table 4 on page 21 the maximum pressure of water vapor is 25 mmHg.
So don't forget to have some water vapor in the atmosphere.