73. In previous years, the NPM pointed out in its reports, in addition to the deficiencies or good practices observed during the visits, certain material matters that it examines when visiting places of deprivation of liberty. Accordingly, after these five years of activity, it is considered that all places where persons deprived of liberty remain, whether short-, mean- or long-term, should meet certain minimum criteria or safeguards (as mentioned in paragraph 107c of Annual Report 2011 of the SPT), in accordance with international and domestic laws on the matter, for such deprivation of liberty to be carried out without detriment to the fundamental rights of persons deprived of liberty. The intention, in addition to safeguarding such fundamental rights, is for such criteria, established from an essentially preventive point of view, and based some of them on the recommendations already made by the SPT itself, the CPT and the Ombudsman’s Office, may be of use for the personnel working at places of deprivation of liberty and their superiors, as a basis for constructive dialogue on which to improve the situation and correct any deficiencies that may be observed. 74. As explained in the first annual report of the NPM, including the work performed in 2010, the maximum duration of each type of deprivation of liberty is considered a determining factor to establish the minimum criteria applicable to each case. Thus, those considered necessary for short-term deprivation of liberty, estimated by days; for mean-term deprivation of liberty, which may have a duration of up to two months, for long-term deprivation of liberty, which may have a duration of more than three months and for deprivation of liberty at special purpose places, are set out below. III.1 Criteria to be met at facilities for short-term deprivation of liberty 75. It is of interest to point out, firstly, that the duration of deprivation of liberty at police facilities is relatively short (the average duration of detentions is approximately 24 hours) and, accordingly, it cannot be expected that the conditions in which such detention takes place should be the same as in other places, where people may be deprived of liberty for much longer time, as could be, for example, penitentiary 49