DIN ISO 5199, February 1987: Centrifugal pumps, technical requirements, class II.
The following sections of this standard contain requirements and recommendations concerning the sealing of shafts by mechanical seals:

3 Definitions (especially 3.16 to 3.22)

4.3.2 Balance and vibration

4.4.4.6 External bolting

4.5.3 Vent, pressure gauge and drain

4.5.5 Auxiliary pipe connections

4.5.6 Connections Identification

4.8.3 Axial adjustment

4.11 Shafts and shaft sleeves

4.11.2 Surface roughness

4.11.3 Shaft deflection

4.11.4 Diameter

4.11.6 Axial movement

4.11.7 Securing and sealing of shaft sleeve

4.11.8 Arrangement of shaft sleeve, if fitted

4.13 Shaft sealing

4.13.3 Mechanical seals (especially 4.13.3.4)

4.13.4 Auxiliary piping for stuffing box and mechanical seal

4.13.5 Mechanical design of auxiliary piping

4.17.3 Baseplate design

7.3 Securing of rotating parts for transport

7.4 Openings

Annex D: Typical seal arrangements

Annex E: Piping arrangements for seals

Annex H: Checklist