The JIS B 9901 series consists of Part 1 : Gas removal media and Part 2 : Gas removal filters. The performance test of gas removal materials is tested at small scale and low flow rate in order to select filter materials. On the other hand, the performance test of the gas removal filter is tested at practical scale size and flow rate. Performance tests measure pressure drop, removal efficiency, removal capacity, and retentivity of gas removal media and gas removal filters. The equipment, test conditions, and operating methods for those measurements are described. In addition, the report shows how to estimate removal efficiency and removal capacity when used as a gas removal filter based on the test results of gas removal materials, and also lists gas concentration measurement methods for performance evaluation.

Based on the international standard ISO16890 series established in 2016, JIS B 9908, the JIS standard for general ventilation air filters, was established in 2019. The concept of particulate matter efficiency J-ePMx was newly introduced. Market confusion is expected because the filter category has changed significantly. This section explains the contents of the JIS standard, the background and problems regarding to the standard change. Also, the transition of the JIS standard and the classification according to the 2019 edition, comparison with existing overseas standards, current application status and future issues.

JIS B 9927-1〜-5 based on ISO 29463-1〜-5 was established. This is a standard for classifying EPA, HEPA and ULPA filters. In the test procedure, first, MPPS at the filter sheet media is determined by performing efficiency measurement by particle size at the media velocity at the filter rate air volume, and then the scanning leak test of the filter by the MPPS test particles (local efficiency), the overall efficiency test is performed, and the filter class classification is performed from the results. There is no provision for filter pressure drop in this classification. The charged medium filter reflects the result of performing a discharge treatment in a flat sheet filter medium test.

The standard test method uses oily liquid test aerosol, the flat sheet filter medium test is performed with mono-disperse aerosol, and the automatic scanning leak test and the overall efficiency test are performed on mono-disperse or poly-disperse aerosol.

Although it is considered that there are almost no problems with the test of the glass fiber medium filter by the standard test method, it is considered necessary to improve the use of solid particles and the test method in the case of a filter having an MPPS of 0.1μm or less.

In addition, Japanese conventional HEPA filters (0.3μm efficiency 99.97%) could be classified as ISO E30 (EPA filter groups).

This study examined the relationship between the age-related positivity effect (ARPE) of odor-evoked involuntary autobiographical memories and subjective well-being. In this study, a diary method was used to measure memory characteristics of autobiographical memories recalled by odor stimuli in daily life in 200 young and 200 older adults. They were also asked to complete the subjective well-being scale. The results showed that older adults recalled more positive memories than younger adults, suggesting the ARPE does occur. A weak but significant correlation was found between valence rating of autobiographical memory and subjective well-being in older people.