CHAPTERS:An Optical Brightener Handbook
Step 1: Getting Started
B. Materials
1. Because Optical Brightener is so pervasive when dealing with cotton products, the first hurdle a would-be monitor must overcome is to find a reliable source of untreated cotton pads.
One source for purchasing untreated cotton pads is:
V.W.R. Scientific Products
200 Center Square Rd.
Bridgeport, New Jersey 08014
1-800-932-5000
All cotton pads, regardless of their source, should be checked under a long wave Ultra Violet fluorescent light to make sure they do not contain Optical Brightener before they are used.
2. It is necessary to have a rigid sampling device that will hold the cotton pad securely in place while allowing water to easily pass through it.
Optical Brightener Sampling Devices
In open pipe or stream sampling it is recommended that the rigid sampling device be non-metal plastic or a vinyl coated black 1/2" wire cage that consists of two hinged pieces that measure approximately 5" by 5". This cage should be fabricated so that it will rest at approximately a 30 to 45 degree angle. The open end of this cage is closed with an elastic band.
In sampling catch basins it is recommended that the sampling device be constructed from 1/2" mesh black plastic netting that is closed at the bottom to create a bag. Small stones are placed in the bottom of the bag so that it will not float. The cotton pad sampler is then stapled above these stones to the plastic netting.
One source for purchasing sampling devices is:
Winchester Fishing Co.
18 Washington St.
Gloucester, Mass. 01930
(978) 281-1619, 283-0757
3. A long wave 4-6 watt fluorescent Ultra Violet (U.V.) light should be used for analysis. Although the most costly component of O.B. sampling, this is critical as the U.V. light must be of sufficient strength and quality to make definitive results possible.
One source for purchasing a long wave U.V. 4-6 watt fluorescent light is:
V.W.R/Scientific Products
200 Center Square Rd.
Bridgeport, New Jersey 08014
1-800-932-5000
