Bailers and Peristaltic Pumps
Bailers boast several advantages over other methods of media sampling. Specifically, when you compare them to peristaltic pumps--well, there really isn't any comparison. Bailers are less expensive, easier to use, more reliable for sample integrity and accuracy, and safer for sample storage.
Cost: Peristaltic pumps, due to their design characteristics, tend to be prohibitively expensive for many applications where a bailer is more appropriate. Peristaltic pumps are better suited to use in lab settings and other non-submersed applications. They operate by running rollers over a tube, thereby causing liquids to be moved. Because of the quantity of moving parts and precision movement required, these pumps are not well suited to bailing applications.
Ease of use, reuse, and disposability: Peristaltic pumps are generally much more expensive than bailers. Bailers can be made of much more inexpensive, non-contaminative, materials which renders them suitable for one-time use. Or depending on the materials, they can be decontaminated, suitable for repeated use.
Contamination: Regarding sample contamination, peristaltic pumps can be problematic since one of two methods can be employed. Either the entire pump can be lowered into the media, which could cause both significant disturbance and contamination to the sample media, or a length of tubing can be inserted. This method would also place the sample at risk of contamination, both from external sources and from cross-contamination within the water being sampled (i.e., water from different levels being pulled in as samples are taken). Additionally, precise depth of the tubing would be difficult to ensure.
Quality: Our bailer manufacturer complies with ISO quality standards and is able to ensure clean-room manufacturing quality, thus guaranteeing no contamination of sample media.
Accuracy of Sample Gathering: With proper equipment, delivery of the bailer to the proper depth is easily accomplished. It's a cinch, compared to the tubing used by peristaltic pumps, which is typically coiled for storage and transport. Such coiling would make delivery of the tube end to the proper depth difficult to ensure.
Sample Storage: Another advantage of the bailer over the peristaltic pump is sample storage. Since the sample is gathered and stored inside the bailer, there is no danger of contamination by transferring from tube to bag, bottle, or container.
