Work done while employed by an international organization does not accumulate the employment requirement. As an exception to this is working as a UN peacekeeper or in other crisis management forces where the Finnish Government is responsible for the payment of wages.
The review period of the employment requirement can be extended if the international organizations a person has worked for have received funding from Finland. Organizations like these are the UN and it’s specialized agencies such as ILO, UNESCO ja UNICEF, EU, OECD, GATT, the World Bank, Council of Europe, Nordic Council of Ministers, Nordic Council, CIMO etc.
The review period can be extended by seven years at most. Please note that, for example, the International Red Cross is not an organization between the governments of different countries, so work there does not extend the review period.