The decree sets out the rules for using offsets to comply with the new carbon tax establishes some high-level criteria that projects have to meet. The main criteria require that emission reductions or removals must: -Have been verified by auditors accredited by either the UNFCCC, Colombia's National Accreditation Body (Organismo Nacional de Acreditación de Colombia, or ONAC), or a member of the International Accreditation Forum (IAF) that has accreditation services for greenhouse gases under ISO 14065; -Have taken place in Colombia (Chapter 2, Article 2.2.11.2.1, Item 1), noting that Paragraph 4 of the same chapter allows for non-CDM emission reductions or removals from outside of Colombia until the end of 2017; -Have been issued by GHG certification programs that have a publicly available registry (Chapter 2, Article 2.2.11.2.1, Item 2); -Rely on methodologies that have either been approved by the UNFCCC, or have undergone a public stakeholder consultation and can be audited by properly accredited auditors (Chapter 2, Article 2.2.11.2.1, Item 3); -Meet regulatory surplus requirements (Chapter 2, Article 2.2.11.2.1, Item 4); -Be retired in the originating GHG certification program before being issued in the National Registry of Emission Reductions (Chapter 2, Article 2.2.11.2.1, Item 5), noting that Article 4 sets out procedures for complying with the law prior to the operation of the National Registry; -Be certified by the accepted GHG certification program; -Have been generated on or after 1 January 2010 (Chapter 2. Paragraph 1); and -Only be ex post, meaning that projections of/for emission reductions or removals will not be accepted.