M Mokhtari , K Naddafi , A.h Mahvi , S Naseri ,
Volume 3, Issue 3 (6-2005)
Abstract
There is a need for simple and inexpensive water supply systems in small communities, mainly because of high costs and water resource shortages. Ceramic filters used as a Point-of-Use (POU) system could serve as a safe and inexpensive means for supplying water. In this research we looked at the possibility of using Iranian traditional ceramics as filters for drinking water, bearing in mind the importance of ceramic filters as a POU system. A number of parameters relating to water quality were measured before and after filtration through a ceramic pipe wall. We used ceramic pipes made of clay (with 90% purity). It turned out that ceramic filters are capable of eliminating indicator microorganisms and turbidity to a considerable degree. They can also remove 70% of the water's color. But this system could not eliminate Dissolved Solids, Electrical Conductivity, Hardness and the Nitrate ion content of water. Using Mann-Withney U Test and T- Test, it is confirmed that increasing the thickness and number of ceramic pipes is not effective for improving some water parameters. This research showed ceramic filters can be useful for household water treatment in places where there is microbial pollution or high turbidity.
Farideh Golbabaei, Ali Faghihi-Zarandi, Ahmadreza Shokri, Mohammadreza Baneshi, Pedram Ebrahimnejad, Asghar Sedigh Zadeh,
Volume 10, Issue 2 (10-2012)
Abstract
Background and Aim: Bioaerosols are one of the most important agents that cause post operating infections in hospitals. Surgical masks are recommended for prevention of bioaerosols transmition in operating rooms. This study aimed at evaluation of submicron particle filtration efficiency of domestic and imported surgical masks.
Materials and Methods: In this cross sectional study, 5 types of surgical masks that have the most utilization in operating rooms of country’s hospitals including domestic and imported surgical masks were tested. To evaluate all samples, the submicron particle filtration measurements were carried out based on ISIRI 6138 and American DOP standards. Filtration efficiency calculations and pressure drop measurements were performed and the results were analyzed using statistical tests.
Results: Results showed that particle filtration efficiency of domestic and imported masks were 56.130% (±10.7) and 31.906% (±7.062) respectively. Also, filtration efficiency in domestic masks were more than imported masks (P> 0.001). Among all samples, Arman mask had the most filtration efficiency (66.5475 % ±6.14951), where the least (27.8275 % ±4.44152) filtration efficiency (P> 0.001) belongs to Blosom. The maximum mean of pressure drop in Arman mask (35 ±2. 58 Pa) and the least mean of pressure drop in Zist filter mask (11 ±1.82 Pa) were observed.
According to the effect of filtration efficiency and pressure drop on general quality of mask, the quality factor of masks were also evaluated. Results showed that Zist filter mask had the most quality factor (0.068) while Blosom had the least quality factor (0.016).
Conclusion: This research showed that domestic surgical masks have a better quality toward imported surgical masks but can not obtained quality confirmed by standards, yet.
To reduce respective infections and prevalence of diseases, it is recommended using filters with suitable physical characteristics and also carrying out test of surgical masks before supplying.
