Table 1.

Factors and levels of experimental design.

Type	Factor Name	Units	Type	Levels	L [1]	L [2]	L [3]	L [4]
A [Categoric]	OMF density	mT	Ordinal	4	0	5	42	80
B [Categoric]	Exposure time	min	Ordinal	2	30	60	–	–
C [Categoric]	Exposure type	–	Nominal	2	EB	EC	–	–
D [Categoric]	Operating conditions	–	Nominal	2	CFC	UFC	–	–