The motorized blade isn't always the most dangerous thing about using a chain saw. Trees contain enormous amounts of energy that can release in ways both surprising and lethal. If a tree stands at an angle, it becomes top-heavy and transfers energy lower in the trunk. When sawed, it can shatter midcut and create a so-called barber chair. The fibers split vertically, and the rearward half pivots backward. "It's very violent and it's very quick," says Mark Chisholm, chief executive of New Jersey Arborists.
Compared to reverse osmosis, filtration is considered effective when it comes to selective elimination of much smaller molecular compounds such as chlorine and pesticides. The other factor that makes filtration less costly is that it does not require a lot of energy needed in distillation and reverse osmosis. It is an economic method of water purification because little water is lost during purification.
The Lifestraw go simplifies water purification by allowing users to scoop water from a river or other unsafe water source into the bottle, screw the lid on, and sip clean water through the mouthpiece. We have not had the opportunity to test the Lifestraw go. We would be interested in comparing it to the Sawyer Personal Water Bottle. Our next post will be a test of the Sawyer bottle.

Ultraviolet light (UV) is very effective at inactivating cysts, in low turbidity water. UV light's disinfection effectiveness decreases as turbidity increases, a result of the absorption, scattering, and shadowing caused by the suspended solids. The main disadvantage to the use of UV radiation is that, like ozone treatment, it leaves no residual disinfectant in the water; therefore, it is sometimes necessary to add a residual disinfectant after the primary disinfection process. This is often done through the addition of chloramines, discussed above as a primary disinfectant. When used in this manner, chloramines provide an effective residual disinfectant with very few of the negative effects of chlorination.
Within the United States Marine Corps, the reverse osmosis water purification unit has been replaced by both the Lightweight Water Purification System and Tactical Water Purification Systems.[14] The Lightweight Water Purification Systems can be transported by Humvee and filter 470 litres (120 US gal) per hour. The Tactical Water Purification Systems can be carried on a Medium Tactical Vehicle Replacement truck, and can filter 4,500 to 5,700 litres (1,200 to 1,500 US gal) per hour.[citation needed]

A nice feature of the Sawyer system is the benefit of using the same filter as a water treatment bottle, inline on a hydration pack, as an ultra light drink straw and attached to a faucet with the included faucet adaptor. If purchased with the faucet adaptor kit, it can be configured to drink straight from the tap during boil alerts or in areas of natural disasters such as floods, hurricanes, and earthquakes. The kit also provides hydration pack assembly kit for installing the inline filter on a hydration pack.


Use water purification and disinfection tablets. Water purification tablets are made of either chlorine dioxide or iodine and kill bacteria and viruses in water. To use these tablets, fill a pitcher or jar with water and add enough tablets to treat the water. One tablet typically treats 1 quart (1 L) of water. These tablets generally need anywhere from 30 minutes to four hours to work.[4]
My first path was to go with a Pelican combination whole house filter and salt free water softener. My plumber and others said whole house filter was the way to go for pure water and clear ice, not so much. Even Pelican suggested RO was not needed with the whole house filter. While I’m pleased with the Pelican system, the water is indeed soft and clean throughout my home, my faucets don’t ... full review
Sip on pure, clean water with the addition of the APEC Ultimate 6-Stage Reverse Osmosis Water Filter System for home. This reverse osmosis system is easy to mount under the sink and earns top marks for easy installation and excellent customer service. With super capacity filters, you only need to change the filters once a year to enjoy clean and safe water every day.
The first part of the purification tag team must eliminate microorganisms, like harmful bacteria and parasites. There are a handful of tried and true methods for doing this. The most familiar is boiling. Simply bringing water up to its boiling point of 212 degrees Fahrenheit will kill almost all microorganisms, so just a few minutes of boiling will do the job.
That brings us to filtration by manufactured filters. These devices allow us to go into microfiltration and ultrafiltration. By simply running the water through these porous ceramic filters we can effectively remove bacteria and viruses depending on the quality of the filter and the pore size. See chart above. This is where high quality filters such as the Katadyn Combi Filter can filter down to 0.2-micron level capturing Giardia, Crypto, bacteria and most viruses. Some filters are chemically impregnated to ensure complete removal of bacteria. The information below will give more detail.
Radium Removal: Some groundwater sources contain radium, a radioactive chemical element. Typical sources include many groundwater sources north of the Illinois River in Illinois, United States of America. Radium can be removed by ion exchange, or by water conditioning. The back flush or sludge that is produced is, however, a low-level radioactive waste.

The booster pump included with this tankless reverse osmosis system requires electricity but helps to maximize the efficiency of the system. It can achieve up to a 1:1 ratio of purified to wastewater. However, in real-world use, some people found that wastewater was more like 2 gallons for every 1 gallon of purified water produced. iSprings points out that many factors affect this efficiency rating, so some variance in results is to be expected.


Brackish water reverse osmosis refers to desalination of water with a lower salt content than sea water, usually from river estuaries or saline wells. The process is substantially the same as sea water reverse osmosis, but requires lower pressures and therefore less energy.[1] Up to 80% of the feed water input can be recovered as fresh water, depending on feed salinity.
Bromine and iodine can also be used as disinfectants. However, chlorine in water is over three times more effective as a disinfectant against Escherichia coli than an equivalent concentration of bromine, and over six times more effective than an equivalent concentration of iodine.[16] Iodine is commonly used for portable water purification, and bromine is common as a swimming pool disinfectant.

When particles to be removed do not settle out of solution easily, dissolved air flotation (DAF) is often used. After coagulation and flocculation processes, water flows to DAF tanks where air diffusers on the tank bottom create fine bubbles that attach to floc resulting in a floating mass of concentrated floc. The floating floc blanket is removed from the surface and clarified water is withdrawn from the bottom of the DAF tank. Water supplies that are particularly vulnerable to unicellular algae blooms and supplies with low turbidity and high colour often employ DAF.[6]:9.46


The tourist season got off to a grisly start this year in Gulf Shores, Ala. During a two-day period in early June, four men drowned after being caught in rip currents. The unusually strong currents were invisible, not even roiling the surface. Rip currents occur when water rushing back from the shoreline is channeled through a narrow gap between two sand bars, accelerating the outward flow.
The clarified water is then fed through a high-pressure piston pump into a series of vessels where it is subject to reverse osmosis. The product water is free of 90.00–99.98% of the raw water's total dissolved solids and by military standards, should have no more than 1000–1500 parts per million by measure of electrical conductivity. It is then disinfected with chlorine and stored for later use.[citation needed]
Plumbosolvency reduction: In areas with naturally acidic waters of low conductivity (i.e. surface rainfall in upland mountains of igneous rocks), the water may be capable of dissolving lead from any lead pipes that it is carried in. The addition of small quantities of phosphate ion and increasing the pH slightly both assist in greatly reducing plumbo-solvency by creating insoluble lead salts on the inner surfaces of the pipes.
Some small-scale desalination units use 'beach wells'; they are usually drilled on the seashore in close vicinity to the ocean. These intake facilities are relatively simple to build and the seawater they collect is pretreated via slow filtration through the subsurface sand/seabed formations in the area of source water extraction. Raw seawater collected using beach wells is often of better quality in terms of solids, silt, oil and grease, natural organic contamination and aquatic microorganisms, compared to open seawater intakes. Sometimes, beach intakes may also yield source water of lower salinity. 
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