Hydro Annual Report 2011b

sold or demerged during the year have not been included. All
consolidated operations that have been part of Hydro during
parts of 2011 are still included in our health and safety data for
the period the unit was owned by Hydro.
Data relating to health, environment and safety has been prepared
by individual reporting units in accordance with corporate
procedures. This applies to all Hydro’s operations, including
consolidated subsidiaries and units for which we have operator
responsibility. This applies if not otherwise stated.
Non-operated, minority-owned operations are not included in
the reported data except for greenhouse gas emissions from
Hydro’s ownership equity, as reported on page 51 and 57. In
addition, we include some examples and other qualitative information
that demonstrate how we promote our policies toward
these operations.
It is not the intention to include detailed information that is
primarily of significance for individual sites, processes, activities
and products.
Information in the reporting is based on input from many units
and sources of data. Our emphasis has been to ensure that the
information is neither incomplete nor misleading. However, the
scope of the report, and the varying certainty of data in connection
with diversity and HSE matters, for example, may mean that
there are uncertainties regarding some of the figures reported.
Hydro’s acquisition of vale’s aluminium activities was closed on
february 28, 2011. Environmental and financial data relating to
vIABIlItY perForMAnCe
About the reporting
71
this part of the transaction has been included for the entire year
of 2011. Historical environmental data have been recalculated
to reflect current operations. Headcount, safety and work environment
data are included from the closing date.
Assurance principles and scope
We have requested our company auditor to review the information
relating to viability performance in accordance with the
AA1000 Assurance Standard (2008) (AA1000 AS). This is an
assurance standard for this type of reporting, and the review
considers both the accountability principles and performance
information. The review was conducted in accordance with the
international audit standard ISAE 3000 – Assurance Engagements
other than Audits or Reviews of Historical financial
Information. This year, we have adopted a limited level of assurance,
which is deemed as being equal to a moderate level of
assurance as defined by AA1000AS. for the underlying systems,
the reader is referred to Hydro’s steering documents as
described under Corporate Governance, see page 123. The
auditor’s review report is presented on page 72. Based on the
AA1000 AS, the auditor comments on our adherence to the
AA1000 APS. We describe our adherence to the AccountAbility
principles in our Annual Report 2011 on the web, see www.
hydro.com/reporting2011
Learn more:
www.hydro.com/gri
www.hydro.com/globalcompact
www.hydro.com/principles
www.hydro.com/reporting2011