Digital Equipment 300 Series AXP Reference Manual page 268

Appendix Overview
Safety
Warnings for
UK Installations
Only
F–4
Except at the connector that plugs into the host, clearance and
creepage distances of Xmm and Ymm, as listed in Table F–3,
must be maintained between the approved module and other
parts of the host, including expansion cards.
Table F–3 Clearance and Creepage Distances
Clearance Creepage
Xmm Ymm
1
2.0 2.4 (3.8)
2.6 3.0 (4.8)
4.0 5.0 (8.0)
4.0 6.4 (10.0)
1
The distances shown in parentheses apply in an uncontrolled environment
where heat, humidity, and temperature may fluctuate.
Ports indicated by the safety warning label do not provide
sufficient isolation to satisfy the requirements of the relevant
parts of standard BS6301. Therefore, any product connected to
this port must meet one of the following conditions:
• Be covered by the Office of Telecommunications (OFTEL)'s
General Approval NS/G/1234/J/100003
(All products supplied by Digital comply with this General
Approval.)
• Have been approved to the relevant parts of standard
BS6301
• Have previously been evaluated against British Telecom
(Post Office) Technical Guide 2 or 26 and given permission to
attach
Any other use of this product invalidates approval.
Voltage Used or Generated by Other
Parts of the Host or Expansion Card
Vrms or Vdc
Up to 50
Up to 125
Up to 250
Up to 300