Once the filters have reached constant weight store in the • appropriately numbered Millipore Petri-slides until required. On TSM log sheet record the number of the Petri-slide along with the weight of the filter stored in the Petri-slide. Always do the initial and final post-sampling weighing of the • filters on the same balance. Suspended Matter (SM) Analysis (total, organic and inorganic) After the NRS Samplers have collected the Suspended Matter • sample in the field: Place filters in glass petri dishes, each labelled with the same number • as that on the petri slide from which each filter came. Each petri dish will contain 3 small balls of aluminium foil on which the filter will sit . Place petri dishes on a tray (cake tin), cover with a sheet of aluminium • foil and place in an oven at 75o C for approximately 3 hours. Remove from oven and let cool (around 15 minutes). • Weigh each filter, record weight on the TSM log sheet against the • same number and return the filter to the same petri dish. Return petri dishes to the oven at 75o C for approximately another 1-2 • hours. Remove, cool and weigh again. • Generally after 2 weighings, the filters should have reached constant • weight. If there is more than 0.2 mg difference between the first and second weighing, repeat the drying/weighing process. Determine the TSM weight by subtraction of the pre- filtration weight • from the post-filtration weight. Take note of the sample volume that was filtered through the filter. • Calculate the weight per volume (Total). • Return filters to glass petri dishes and place petri dishes on the floor • of a muffle furnace (note the position of each of the numbered dishes as the numbering on the dishes will be removed during the muffling process). Cover the dishes loosely with a sheet of aluminium foil and program the muffle furnace to 450o C. After the furnace has reached this temperature, wait 3 hours before programming the temperature of the furnace to 20o C. When the furnace has reached 20o C, remove the dishes and filters and weigh immediately.
• Once the filters have reached constant weight store in the appropriately numbered Millipore Petri-slides until required. On TSM log sheet record the number of the Petri-slide along with the weight of the filter stored in the Petri-slide. • Always do the initial and final post-sampling weighing of the filters on the same balance. Suspended Matter (SM) Analysis (total, organic and inorganic) • After the NRS Samplers have collected the Suspended Matter sample in the field: • Place filters in glass petri dishes, each labelled with the same number as that on the petri slide from which each filter came. Each petri dish will contain 3 small balls of aluminium foil on which the filter will sit . • Place petri dishes on a tray (cake tin), cover with a sheet of aluminium foil and place in an oven at 75o C for approximately 3 hours. • Remove from oven and let cool (around 15 minutes). • Weigh each filter, record weight on the TSM log sheet against the same number and return the filter to the same petri dish. • Return petri dishes to the oven at 75o C for approximately another 1-2 hours. • Remove, cool and weigh again. • Generally after 2 weighings, the filters should have reached constant weight. If there is more than 0.2 mg difference between the first and second weighing, repeat the drying/weighing process. • Determine the TSM weight by subtraction of the pre- filtration weight from the post-filtration weight. • Take note of the sample volume that was filtered through the filter. • Calculate the weight per volume (Total). • Return filters to glass petri dishes and place petri dishes on the floor of a muffle furnace (note the position of each of the numbered dishes as the numbering on the dishes will be removed during the muffling process). Cover the dishes loosely with a sheet of aluminium foil and program the muffle furnace to 450o C. After the furnace has reached this temperature, wait 3 hours before programming the temperature of the furnace to 20o C. When the furnace has reached 20o C, remove the dishes and filters and weigh immediately.
AA_NRS_BGC_Handbook_ver2.2.docx