• Data reference period
• Geographic localization (Portugal)
• Type of waste (CER-stat)
• Type of waste management operation

• WASTE:  Any substance or object which the holder discards or intends or is required to discard, according Waste Framewok Directive
• DISPOSAL OF WASTE:  Any operation which is not recovery even when the operation has as a secondary consequence the reclamation of substances or energy.
• WASTE MANAGEMENT:  The characteristic activities of waste management include: collection, transport, storage, treatment, recovery and disposal of waste, including monitoring the discharge sites after the respective facilities have been closed down, as well as planning these activities. Waste management aims, above all, to prevent or reduce the harmfulness of waste, namely through recycling and changing the production processes, by adopting cleaner technologies, as well as alerting the economic agents and the consumers. In terms of subsidies, waste management aims at recovering waste, namely through recycling or disposing of it in the appropriate manner.
• RECOVERY OF WASTE:  Any operation the principal result of which is: a) waste serving a useful purpose by replacing other materials which would otherwise have been used to fulfil a particular function; b) waste being prepared to fulfil that function, in the plant or in the wider economy.
• REFERENCE PERIOD:  Period to which the information refers and which may be a specific day or a time interval (month, fiscal year, calendar year, among others).

(Hazardous waste by kind of waste / Total waste by kind of waste)*100