Pressure relief valve is one of the most important devices used on the security of pipelines, since it is responsible to guarantee the integrity of the installations. Generally, the response and behavior of a relief valve during its transient is unknown by users, who employ simplified and static analysis to design the pipeline, further, the information provided by manufactures is limited. The f...

According to WHO, at any one time, around 50 per cent of medical equipment in lowand middle-income countries cannot be used because of lack of maintenance or spare parts.1 We have found that unwillingness or inability to repair equipment and put it back in use is also a major cause. New equipment is made available by different international non-government organisations (INGOs) competing with on...