[QUOTE=KASOL;37461]I am well aware of the Norsok D-010 since I work here in Norway. 
Edit: Table 22 Casing cement:
Requirement:
[B]Casing through hydrocarbon bearing formations: [/B]
Shall be defined based on requirements for zonal isolation. Cement should cover potential cross-flow
interval between different reservoir zones.
For cemented casing strings which are not drilled out, the height above a point of potential inflow/ leakage point / permeable formation with hydrocarbons,
shall be 200 m, or to previous casing shoe, whichever is less.
Qualification
The cement shall be verified through formation strength test when the casing shoe is drilled out. Alternatively the verification may be through exposing the
cement column for differential pressure from fluid column above cement in annulus. In the latter case the pressure integrity acceptance criteria and
verification requirements shall be defined.
2. The verification requirements for having obtained the minimum cement height
shall be described, which can be
• verification by logs (cement bond, temperature, LWD sonic), or
• estimation on the basis of records from the cement operation (volumes
pumped, returns during cementing, etc.).
3. The strength development of the cement slurry shall be verified through
observation of representative surface samples from the mixing cured under a
representative temperature and pressure. For HPHT wells such equipment
should be used on the rig site.[/QUOTE]
Readers might also be interested with - G.Failure Modes- last page, in the pdf document, links of which I posted to Kasol. The document read in its entirety will shed even more light on the issue of cement failure. http://www.npd.no/Global/Norsk/5%20-...dard_D-010.pdf