• Collecting snow samples to quantify light absorbing particles
  • Monthly samples collected near Huaraz, Peru

Black carbon filtering

This page contains directions on how to work with the filters for the ACSP black carbon filtering technique. Details on the research project can be found at: The Cryosphere Article

You will have collected your snow sample and it will be in a sealed ziplock bag. You will have your basic filtering gear which includes a syringe, filters, a filter holder, and some coin holders to preserve the filters. The first video shows how to load up the filter holder for filtering:

Loading your filter

Once your filter is loaded into the filter holder, you will need to load the syringe and attach the filter holder to the syringe:

Loading the syringe

Next, you will need to use the syringe to slowly push the water through the filter. Watch the video for tips on filtering speed as well as on how to uniformly distribute the contaminants on the filter.

Filtering

You will next need to remove the filter holder from the syringe and reload the syringe. You will typically do this ten times so that you filter a total of 600 ml of water. If the filter appears to be quite dirty, stop earlier and make a note of how much water was filtered.

Re-loading the syringe

Finally, after finishing filtering, you will need to remove the filter from the filter holder and put it into the coin holder for preservation and transportation.

Preserving the filter

Equipment:

The following links are the websites where I get the equipment for filtering.

Filters, Pall Tissuquartz 25 mm circles from neobits

Filter holders, Millipore 25 mm swinnex Luer lock filter holders

Syringes, 60 cc luer lock

Coin holders, 25mm coin holders with white rings

The above suppliers have been reliable and fast for me in the past, but not necessarily the least expensive. BE AWARE THAT IN SOME CIRCUMSTANCES, IT HAS TAKEN SEVERAL MONTHS TO RECEIVE EQUIPMENT. SOME OF THESE ITEMS ARE NOT HIGH DEMAND ITEMS SO THEY ARE NOT ALWAYS STOCKED. Use of a different filter type could have an unknown affect on results with my instrumentation, so it is highly recommended to use the tissuquartz filters for consistency. Other items necessary include plastic bags. I buy 1 gallon (4 liter) ziploc plastic bags from the grocery store.