. Author manuscript; available in PMC: 2019 Feb 1.

Published in final edited form as: Space Sci Rev. 2017 Dec 13;214(1):19. doi: 10.1007/s11214-017-0439-4

Table 3.

OCSSG cleaning guidelines summary (Mahaffy et al. 2004). Bold text are outside the capabilities of identified industrial ATLO facilities including those available for OSIRIS-REx

OCSSG cleanliness level	1	2	3
Nonvolatile residue (NVR) level^a	A/2	A/100	AA3
	(500 ng/cm²)	(10 ng/cm²)	(1 ng/cm²)
Particulate cleanliness level^a	400	200	25
Outgassing flux	100 ng/cm²/hr	10 ng/cm²/hr	1 ng/cm²/hr

IEST (2002)