13 43. The issue of what is a reasonable size for a police cell (or any other type of detainee/prisoner accommodation) is a difficult question. Many factors have to be taken into account when making such an assessment. However, CPT delegations felt the need for a rough guideline in this area. The following criterion (seen as a desirable level rather than a minimum standard) is currently being used when assessing police cells intended for single occupancy for stays in excess of a few hours: in the order of 7 square metres, 2 metres or more between walls, 2.5 metres between floor and ceiling. b. Imprisonment 44. In introduction, it should be emphasised that the CPT must examine many questions when visiting a prison. Of course, it pays special attention to any allegations of ill-treatment of prisoners by staff. However, all aspects of the conditions of detention in a prison are of relevance to the CPT's mandate. Illtreatment can take numerous forms, many of which may not be deliberate but rather the result of organisational failings or inadequate resources. The overall quality of life in an establishment is therefore of considerable importance to the CPT. That quality of life will depend to a very large extent upon the activities offered to prisoners and the general state of relations between prisoners and staff. 45. The CPT observes carefully the prevailing climate within an establishment. The promotion of constructive as opposed to confrontational relations between prisoners and staff will serve to lower the tension inherent in any prison environment and by the same token significantly reduce the likelihood of violent incidents and associated ill-treatment. In short, the CPT wishes to see a spirit of communication and care accompany measures of control and containment. Such an approach, far from undermining security in the establishment, might well enhance it. 46. Overcrowding is an issue of direct relevance to the CPT's mandate. All the services and activities within a prison will be adversely affected if it is required to cater for more prisoners than it was designed to accommodate; the overall quality of life in the establishment will be lowered, perhaps significantly. Moreover, the level of overcrowding in a prison, or in a particular part of it, might be such as to be in itself inhuman or degrading from a physical standpoint. 47. A satisfactory programme of activities (work, education, sport, etc.) is of crucial importance for the well-being of prisoners. This holds true for all establishments, whether for sentenced prisoners or those awaiting trial. The CPT has observed that activities in many remand prisons are extremely limited. The organisation of regime activities in such establishments - which have a fairly rapid turnover of inmates - is not a straightforward matter. Clearly, there can be no question of individualised treatment programmes of the sort which might be aspired to in an establishment for sentenced prisoners. However, prisoners cannot simply be left to languish for weeks, possibly months, locked up in their cells, and this regardless of how good material conditions might be within the cells. The CPT considers that one should aim at ensuring that prisoners in remand establishments are able to spend a reasonable part of the day (8 hours or more) outside their cells, engaged in purposeful activity of a varied nature. Of course, regimes in establishments for sentenced prisoners should be even more favourable.