| In force components  | 
Number
  | 
Title | 
Status | 
K.20 (11/22)     | 
Resistibility of telecommunication equipment installed in a telecommunication centre to overvoltages and overcurrents
		 
 | 
In force 
  | 
Guide  (04/2012)     | 
Guide on the use of the overvoltage resistibility for Recommendations ITU-T K.20, K.21 and K.45
		 
 | 
In force 
  | 
     | 
| Superseded and Withdrawn components  | 
Number
  | 
Title | 
Status | 
K.20 (11/88)     | 
Resistibility of telecommunication switching equipment to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (03/91)     | 
Resistibility of telecommunication switching equipment to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (03/93)     | 
Resistibility of telecommunication switching equipment to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (10/96)     | 
Resistibility of telecommunication switching equipment to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (02/00)     | 
Resistibility of telecommunication equipment installed in a telecommunications centre to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (07/03)     | 
Resistibility of telecommunication equipment installed in a telecommunications centre to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (2003) Erratum 1 (01/04)     | 
Correction to table 7/K.20
		 
 | 
Superseded 
  | 
K.20 Amendment 1 (11/04)     | 
New Appendix I - Floating transverse power induction and earth potential rise test for ports connected to external symmetric pair cables
		  
 | 
Superseded 
  | 
K.20 (04/08)     | 
Resistibility of telecommunication equipment installed in a telecommunications centre to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (11/11)     | 
Resistibility of telecommunication equipment installed in a telecommunications centre to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (04/15)     | 
Resistibility of telecommunication equipment installed in a telecommunication centre to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (06/16)     | 
Resistibility of telecommunication equipment installed in a telecommunication centre to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (12/16)     | 
Resistibility of telecommunication equipment installed in a telecommunication centre to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (07/17)     | 
Resistibility of telecommunication equipment installed in a telecommunication centre to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (10/18)     | 
Resistibility of telecommunication equipment installed in a telecommunication centre to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (07/19)     | 
Resistibility of telecommunication equipment installed in a telecommunication centre to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (11/19)     | 
Resistibility of telecommunication equipment installed in a telecommunication centre to overvoltages and overcurrents
		 
 | 
Superseded 
  | 
K.20 (06/21)     | 
Resistibility of telecommunication equipment installed in a telecommunication centre to overvoltages and overcurrents
		 
 | 
Superseded 
  |