Altitude error between two altimeters

[Bernoulli]

I'm not by my referance sources. Under part 135 and 121 what is the allowable altitude error between the captain's altimeter and the FO's altimeter. I know that on the ground the altimeter needs to be within 75 feet of field elevation when you put in the current altimeter setting...but in the air what is the tolerance between the two altimeters? Thanks in advance.

 

[Waldom]

Reference to RVSM [at least in my company FOM]:

On ground: within 75 feet of each other AND within 75 feet of airport elevation.

In flight [at cruise levels] within 200 feet of assigned altitude with no mention of a comparison margin between altimeters.

 

[JAFI]

If you have internet access, you are always near your reference material:

http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?&c=ecfr&tpl=/ecfrbrowse/Title14/14tab_02.tpl

 

[lookin4better]

A note: The Captains altimeter is never wrong. ;-)