| Apex - Vivint |
| Apex / Vivint Alarm |
| 5th of Jul, 2011 by User483728 |
| Shortly after reports of odd encounters with strangers in our small neighborhood ( a stranger offered to help bring groceries inside for me.) a man who spoke quickly & earnestly knocked on our door offering free security equipment & installation. He identified himself as Shawn Monson of Apex Alarm. Polite , but intent on selling the system. Phrases like " we are only here today " , "This is the last free one unless your neighbor Mr--- takes it." Your neighbor , Ms. ... just purchased one ", "This is the best new equipment out there & no one else has it" ,"Our installers are in the neighborhood right now" .... classic lines , I know. We had discussed getting a system after a few home invasions locally , & many more unknown people walking / driving through our small , limited access neighborhood. Some research had been done , but probably not enough. The offer seemed good for equipment received & monthly cost. The installers seemed knowledgeable & professional. We signed & had it installed Nov. 2008. One of the remotes would not work & Shawn said they would get another one to us , still waiting. Neither remote has worked for about a year ; Apex told me I would have to pay for replacements. The system has gone off without reason 3x , & would not respond to code input for several minutes. We were told the system would signal fire / police / medical , & the Apex operator would respond through speaker on unit - it does none of those. Sensors keep falling off doors ; I just re- glue them . At times sensors do not pick up accurately. System has been off more than on ; don't really feel more secure with it. Our contract also has auto renewal clause , & a " Limitation of Lawsuit ; Waiver of jury trial clause. |
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A fence is a freestanding structure designed to restrict or prevent movement across a boundary. It is generally distinguished from a wall by the lightness of its construction: a wall is usually restricted to such barriers made from solid brick or concrete, blocking vision as well as passage (though the definitions overlap somewhat).
Fences are constructed for several purposes, including:
Agricultural fencing, to keep livestock in or predators out
Privacy fencing, to provide privacy
Temporary fencing, to provide safety and security, and to direct movement, wherever temporary access control is required, especially on building and construction sites
Perimeter fencing, to prevent trespassing or theft and/or to keep children and pets from wandering away.
Decorative fencing, to enhance the appearance of a property, garden or other landscaping
Boundary fencing, to demarcate a piece of real property
Contents [hide]
1 Types
2 Requirement of use
3 Legal issues
3.1 History
3.2 United Kingdom
3.3 United States
4 Quotations
5 See also
6 Notes
7 References
[edit]Types
Typical agricultural barbed wire fencing.
Split-rail fencing common in timber-rich areas.
A chain-link wire fence surrounding a field.
Fence of summer garden.
Various types of fencing include:
Barbed wire fence
Chain-link fencing, wire fencing made of wires woven together
Concrete fence, easy to install and highly durable
Chicken wire, light wire mesh for keeping predators out and chickens or other small livestock in
Electric fence
Ha-ha (or sunken fence)
High tensile smooth wire
Hurdle fencing, made from moveable sections
Newt fencing, amphibian fencing, drift fencing or turtle fence, a low fence of plastic sheeting or similar materials to restrict movement of amphibians or reptiles.
Palisade
Pest-exclusion fence
Pet fence Underground fence for pet containment
Picket fences, generally a waist-high, painted, partially decorative fence
Pool fence
Post-and-rail fencing
Roundpole fences, similar to post-and-rail fencing but more closely spaced rails, typical of Scandinavia and other areas rich in raw timber.
Slate fencing in Mid-Wales
Slate fence, a type of palisade made of vertical slabs of slate wired together. Commonly used in parts of Wales.
Snow fence
Spear-top fence
Split-rail fences made of timber, often laid in a zig-zag pattern, particularly in newly-settled parts of the United States and Canada
Stockade fence, a variation of the picket fence that is typically 5 to 6 feet (1.5 to 1.8 m) high with pickets placed adjacent to one another with no space between. This type of fence is commonly used for privacy.
Vinyl fencing
Wattle fencing, of split branches woven between stakes.
Wood-panel fencing
Woven wire fencing, many designs, from fine Chicken wire to heavy mesh "sheep fence" or "ring fence"
Wrought iron fencing, made from tube steel, also known as ornamental iron.
Hedge, including:
Cactus fence
Hedgerows of intertwined, living shrubs (constructed by hedge laying)
Live fencing is the use of live woody species for fences.
Turf mounds in semiarid grasslands such as the western United States or Russian steppes`
Walls, including:
Dry-stone wall or rock fence, often agricultural
Alternatives to fencing include a ditch (sometimes filled with water, forming a moat).
A balustrade or railing is a kind of fence to prevent people from falling over the edge, for example, on a balcony, stairway (see railing system), roof, bridge, or elsewhere near a body of water, places where people stand or walk and the terrain is dangerously inclined.
[edit]Requirement of use
Typical perimeter fence with barbed wire on top.
The following types of areas or facilities often have to be fenced in:
facilities with open high-voltage equipment (transformer stations, mast radiators). Transformer stations are usually surrounded with barbed-wire fences. Around mast radiators, wooden fences are used to avoid the problem of eddy currents.
railway lines (in the United Kingdom)
fixed machinery with dangerous mobile parts (for example at merry go rounds on entertainment parks)
explosive factories and quarry stores
most industrial plants
airfields
military areas
prisons
zoos and wildlife parks
Pastures containing male breeding animals, notably bulls and stallions.
open-air areas that charge an entry fee
domestic swimming and spa pools
[edit]Legal issues
A typical urban fence.
Decorative palace fence (in St Petersburg)
Fences can be the source of bitter arguments between neighbours, and there are often special laws to deal with these problems. Common disagreements include what kind of fence is required, what kind of repairs are needed, and how to share the costs.
In some legislatures the standard height of a fence is limited, and to exceed it a special permit is required.
[edit]History
Servitudes are legal arrangements of land use arising out of private agreements. Under the feudal system, most land in England was cultivated in common fields, where peasants were allocated strips of arable land that were used to support the needs of the local village or manor. By the sixteenth century the growth of population and prosperity provided incentives for landowners to use their land in more profitable ways, dispossessing the peasantry. Common fields were aggregated and enclosed by large and enterprising farmers—either through negotiation among one another or by lease from the landlord—to maximize the productivity of the available land and contain livestock. Fences redefined the means by which land is used, resulting in the modern law of servitudes.[1]
A wattle fence at Sanok-Skansen outdoor museum in Poland
In the United States, the earliest settlers claimed land by simply fencing it in. Later, as the American government formed, unsettled land became technically owned by the government and programs to register land ownership developed, usually making raw land available for low prices or for free, if the owner improved the property, including the construction of fences. However, the remaining vast tracts of unsettled land were often used as a commons, or, in the American west, "open range." As degradation of habitat developed due to overgrazing and a tragedy of the commons situation arose, common areas began to either be allocated to individual landowners via mechanisms such as the Homestead Act and Desert Land Act and fenced in, or, if kept in public hands, leased to individual users for limited purposes, with fences built to separate tracts of public and private land.
[edit]United Kingdom
Ownership of a fence on an ownership boundary varies. Generally title deeds will show which side owns the fence, using a "T" symbol (the leg of the "T" points towards the owner). Commonly the cladding is on non-owners side, enabling access to the posts for the owner when repairs need doing.
Where a fence or hedge has an adjacent ditch, the ditch is normally in the same ownership as the hedge or fence, with the ownership boundary being the edge of the ditch furthest from the fence or hedge.[2] The principle of this rule is that an owner digging a boundary ditch will normally dig it up to the very edge of their land, and must then pile the spoil on their own side of the ditch to avoid trespassing on their neighbour. They may then erect a fence or hedge on the spoil, leaving the ditch on its far side. Exceptions often occur, for example where a plot of land derives from subdivision of a larger one along the centre line of a previously-existing ditch or other feature.
On private land in the United Kingdom, it is the landowner's responsibility to fence their livestock in. Conversely, for common land, it is the surrounding landowners' responsibility to fence the common's livestock out.
[edit]United States
Distinctly different land ownership and fencing patterns arose in the eastern and western United States. Original fence laws on the east coast were based on the British common law system, and rapidly increasing population quickly resulted in laws requiring livestock to be fenced in. In the west, land ownership patterns and policies reflected a strong influence of Spanish law and tradition, plus the vast land area involved made extensive fencing impractical until mandated by a growing population and conflicts between landowners. The "open range" tradition of requiring landowners to fence out unwanted livestock was dominant in most of the rural west until very late in the 20th century, and even today, a few isolated regions of the west still have open range statutes on the books. Today, across the nation, each state is free to develop its own laws regarding fences, but in most cases for both rural and urban property owners, the laws are designed to require adjacent landowners to share the responsibility for maintaining a common boundary fenceline, and the fence is generally constructed on the surveyed property line as precisely as possible.
[edit]Quotations
Wrought iron fencing is often used in historic districts and to surround cemeteries.
"Good fences make good neighbors." - Robert Frost
"A good neighbour is a fellow who smiles at you over the back fence, but doesn't climb over it." - Arthur Baer
"There is something about jumping a horse over a fence, something that makes you feel good. Perhaps it's the risk, the gamble. In any event it's a thing I need." - William Faulkner
"Fear is the highest fence." - Dudley Nichols
"To be fenced in is to be withheld." - Kurt Tippett
"What have they done to the earth?/ What have they done to our fair sister?/ Ravaged and plundered/ and ripped her/ and bit her/ stuck her with knives/ in the side of the dawn/ and tied her with fences/ and dragged her down." - Jim Morrison, of The Doors
"Don't Fence Me In" - Cole Porter
"You shall build a turtle fence." - Peter Hoekstra |
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In agriculture, fences are used to keep animals in or out of an area. They can be made from a wide variety of materials, depending on terrain, location and animals to be confined. Most agricultural fencing averages about 4 feet (1.2 m) high, and in some places, the height and construction of fences designed to hold livestock is mandated by law.
Contents [hide]
1 History
2 Fence laws
3 Modern styles
3.1 Wire fences
3.1.1 Barbed wire
3.1.2 Smooth wire
3.1.3 High tensile wire
3.1.4 Woven wire
3.1.5 Deer fence
3.2 Electric fence
3.3 Synthetic fence
3.4 Wood, pipe and other materials
4 Maintenance
5 See also
6 References
7 External links
[edit]History
Timber agricultural fence (photo taken in 1938).
Historically throughout most of the world, domesticated livestock would roam freely and were fenced out of areas, such as gardens or fields of crops, where they were unwanted. Over time, especially where crop agriculture became dominant and population density of both humans and animals was significant, livestock owners were made to fence their animals in.
The earliest fences were made of available materials, usually stone or wood, and these materials are still used for some fences today. In areas where field stones are plentiful, fences have been built up over the years as the stones are removed from fields during tillage and planting of crops. The stones were placed on the field edge to get them out of the way. In time, the piles of stones grew high and wide.
In other areas, fences were constructed of timber. Log fences or split-rail fences were simple fences constructed in newly cleared areas by stacking log rails. Earth could also be used as a fence; an example was what is now called the sunken fence, or "ha-ha, " a type of wall built by digging a ditch with one steep side (which animals cannot scale) and one sloped side (where the animals roam).
[edit]Fence laws
The tradition of fencing out unwanted livestock prevails even today in some sparsely populated areas. For example, until the mid-20th century, most states in the American West were called "open range" ("fence out") states, in contrast to Eastern and Midwestern states which long had "fence in" laws where livestock must be confined by their owners. Though the open range was part of the western tradition, over time, open range was limited long before it was eliminated completely; first came an obligation to keep cattle from roaming onto state and federal highways, where collisions with fast-moving cars and trucks created a public safety hazard. In addition, voters could voluntarily choose to make certain heavily farmed areas a "herd district, " where livestock needed to be fenced in, a process that also became popular in areas where development of hobby farms created conflicts between large and small landowners. Over time, court cases steadily limited the application of open range law until the present day, where it is the exception rather than the rule in many parts of the American West.
In the United Kingdom, the law is different for private land and common land. On private land it is the owner's responsibility to fence livestock in, but it is the responsibility of landowners bordering a common to fence the common's livestock out.
[edit]Modern styles
[edit]Wire fences
The principle of wire fences is that they are supported mainly by tension, being stretched between heavy strutted or guy-wired posts at ends, corners, and ideally at intervals in longer stretches (every 50 to 300 metres, 150 to 1000 feet). Between these braced posts are additional smaller wooden or metal posts which keep the wires spaced and upright, usually 3 to 6 metre (10 to 20 feet) apart, depending on the style of fencing used.
Traditionally, wire fencing material is made of galvanized mild steel, but galvanized high-tensile steel is now also used in many places. To prevent sagging of the fence, which raises the risk of entanglement or escape, the wire is tensioned as much as the material will safely allow during construction by various means, including a hand-operated fence stretcher (called a "monkey strainer" in some areas) or other leverage devices, a winch, or even by carefully pulling with a tractor or other vehicle.
Wire fences are typically run on wooden posts, either from trees commercially grown in plantations or (particularly in the American West) cut from public lands. When less expensive or more readily available than wood, steel T-posts or star posts are used, usually alternating every 2 to 5 steel posts with a more stable wood post. Non-electrified wire is attached to wooden posts using fencing staples (for intermediate posts, these are fitted loosely, not gripping the wire). Non-electrified wire is held on T-posts by means of wire "clips" made of smooth galvanized wire that wrap around the back of the post and hook onto the wire on either side of the post.[1]
Other than in a truly desert climate, use of rot-resistant wooden posts or steel posts is advised. In the United States, wood with natural rot resistance, such as oak and juniper, was often used until it became in short supply in the 1950s. Then, chemically treated pine and spruce posts became prevalent, and these are also widely used in Britain, together with chestnut. Creosote, pentachlorophenol, and chromated copper arsenate are all widely used in the US and elsewhere for treatment (although some of these chemicals are subject to legal controls).
[edit]Barbed wire
Chain link fence with barbed wire on top.
Detail of barbed wire
The Industrial Revolution brought the first barbed wire (also "barbwire" or just "barb") fences, which were widely used after their introduction in the mid-19th century. This technology made it economically feasible to fence rangeland for the first time. In the United States, introduction of barbed wire contributed to the range wars of that century, as various ranch interests attempted to use barbed wire fences to claim exclusive access to the best pasture and water resources, including those lands in the public domain. It also exacerbated tensions between cattle ranchers and crop farmers, partly when access to water was involved.
Barbed wire has been made by many manufacturers in an almost endless variety of styles. For the most part these were functionally identical. The differences reflected peculiarities of each manufacturing process rather than deliberate design of the end product. Sections of unusual barbed wire are collected by some enthusiasts.
The traditional barbed wire used since the late 19th century and into the present day was made from two mild steel wires twisted together, usually of about 12 or 14 gauge, with about 15-30 twists per metre. Steel barbs were attached every 10–20 cm. Barbs had either two or four points, with the two point design using somewhat heavier and longer barbs. The relative merits of two point vs. four point barbed wire are the subject of deeply held views among many farmers and ranchers, to the extent that both types are still made today.
Typically four strands of barbed wire, with the lowest strand no more than 12 inches (300 mm) from the ground and the top strand at least 48 inches above the ground, make up a legal fence in the western United States. Better-quality fences have five strands, older fences often had only three strands, and just two strands is widely used in Britain if only adult cattle are being contained. Other variations exist, depending on local laws and the purpose of the fence.
Barbed wire is particularly effective for containing cattle. In pastures containing both cattle and sheep, one or two strands of barbed wire is used in conjunction with woven wire to both discourage cattle from reaching over the top of a fence and to keep sheep from crawling under. Though often used in many areas for horses, barbed wire is not advised; its use is considered poor management. There is very high risk of injury occurring when a thin-skinned, fast-moving animal with long legs runs into it or puts a leg through the strands.
[edit]Smooth wire
Smooth (or plain) wire is less likely to cause lacerations than barbed wire
Smooth (or plain) wire is essentially the same product as barbed wire with no barbs – either a two-wire twist or a single strand. Its primary advantage is that it is less likely to cause lacerations and cuts if an animal becomes entangled in it or rubs against it. However, animals will readily lean on mild steel smooth wire, stretching it out of shape or loosening it from the posts, and for this reason it is often used in high-tensile form, which more easily springs back to its original length. Smooth wire fencing is often used as an inexpensive material to safely contain horses and other animals that run a high risk of entanglement, usually in conjunction with a line of electric fence. Smooth wire is also used in securing fence-post braces and other uses where barbed wire is not recommended
[edit]High tensile wire
High tensile (H-T or HT) fencing is a special hard, springy steel wire was introduced in the 1980s and has slowly gained acceptance. The wire may be a single strand plain or barbed wire, or woven mesh, and is capable of much higher tension than mild steel. It permits the use of wider post spacings[2] and is neither stretched easily by animals, nor by fallen trees or branches. It can be insulated and electrified. Because of the wide spacing of the posts, thin metal or wood spacers (or "droppers") may be attached to the wires between posts to maintain their spacing.
Joining HT wire is difficult because of its stiffness and its reduction in strength when bent sharply. However, it may be joined effectively with proprietary clips. HT wire is more expensive than mild steel, but because of the need for fewer posts, the overall cost of the fencing is usually comparable.
Because it does not stretch, animals are less likely to become entangled in HT wire. However, for the same reason, if an animal does become entangled or runs into a few strands at a high speed, it can be deadly, and is sometimes referred to as having a "cheese slicer" effect on the animal.
Trellising for horticultural purposes is generally constructed from HT wire as it is able to withstand a higher crop load without breaking or stretching.
[edit]Woven wire
A kangaroo trapped in ringlock or "sheep" fencing.
A closely-spaced woven wire such as this "no climb" fence has a lower risk of animals becoming entrapped and injured. Note "knots" at each junction securing the wire together
Barbed wire cannot effectively contain pigs, goats or sheep. Where these animals are to be fenced, woven wire (called sheep or pig netting in Britain, sheep fence or hog fence in the United States) is used instead, often with one or more strands of barbed wire at the top. For swine, a ground-level barbed wire strand or electrified wire is used as well to prevent them digging beneath the fence.
Agricultural woven wire is identifiable by wire "knots" wrapped around each intersecting wire. Cheaper forms of wire used in residential fences are often spot welded at junctions and as such are less sturdy and may break, creating a hazard for enclosed animals. Woven wire is more costly to purchase and time-consuming to install than is basic wire, but is often safer and less expensive than wood, pipe, or other materials.
Woven wire with large openings (known as "sheep fence" in the western United States and Ringlock in Australia) has some potential hazards. Animals contained inside the fence can easily put a foot through the wide squares while grazing along the edge of the fenceline or while reaching over it, and then become tangled in the fence. It is also dangerous for wild animals, such as deer, kangaroos or wallabies that attempt to jump such fences.[citation needed] These can become trapped when their back feet clip the fencing and get caught. While they can be cut out, they are often seriously injured and must be euthanized. A variation, called "field fence, " has narrower openings at the bottom and wider openings at the top, which prevents animals from getting their feet entangled while grazing close to the fence, though is of little help if an animal becomes tangled in the openings higher up.
Horses and ponies in particular are safer kept inside woven wire fence with squares of smaller dimensions, such as "no climb" fence with squares that are approximately two inches by four inches. This type of wire is also more effective for containing goats.
Another variant on woven wire is the "hog panel, " which consists of heavy welded wire approximately .25 inches (6 mm) or more in diameter. It resembles field fence in appearance, but is sold in panels rather than rolls and is not easily wrapped or bent. However, larger livestock such as horses or cattle can easily deform hog panels, so if used to contain large animals, it requires supporting rails or pipe on both the top and sides. It has some of the same strengths and weaknesses as field fence. Though animals are less likely to become entangled in it, the wire is far harder to cut if they do.
Chain link fencing is, arguably a form of woven wire, and is occasionally used for some livestock containment. However, due to cost, it is not particularly common for fencing large areas where less-expensive forms of woven wire are equally suitable. When used in small enclosures, it is easily deformed by livestock, resulting in high ongoing maintenance costs.
[edit]Deer fence
Deer and many goats can easily jump an ordinary agricultural fence, and so special fencing is needed for farming goats or deer, or to keep wild deer out of farmland and gardens. Deer fence is often made of lightweight woven wire netting nearly 2 metres (about six feet) high on lightweight posts, otherwise made like an ordinary woven wire fence.
In areas where such a tall fence is unsuitable (for example, on mountains subject to very high winds), deer may be excluded (or contained) by a fence of ordinary height (about 1.5 metres, four feet), with a smaller one of about one metre (three feet) high, about one metre away from it, on the same side as the deer. The additional width prevents deer approaching the fence close enough to jump it.
[edit]Electric fence
Main article: Electric fence
In addition to single strand wire, electric fencing is also made of synthetic materials with fine wire interwoven throughout the fence strands
Detail of electric cord fence with metal interwoven with nylon cord, attached to a steel fence post with a plastic insulator
Electric fencing became widely available in the 1950s and has been widely used both for temporary fences and as a means to improve the security of fences made of other materials. It is most commonly made using lightweight steel wire (usually 14-17 gauge) attached to posts with insulators made of porcelain or plastic. Synthetic web or rope with thin steel wires interwoven to carry the electrical charge has become popular in recent years, particularly where additional visibility is desired.
A fence charger places an electrical pulse from ground to the wire about once per second. The pulse is narrow and usually around 5-20 kV. Animals receive an uncomfortable but harmless shock when contacting the wire, and learn to stay away from it.
[edit]Synthetic fence
This section needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (October 2010)
Main article: Synthetic fence
Horse behind vinyl fence consisting of two vinyl 3-wire "rails" and one vinyl-covered wire
Synthetic fences encompass a wide range or products. Vinyl-coated wire fence is usually based on high-tensile wire with a vinyl coating. Some forms are non-electric, others embed layers of graphite to carry a current from the wire to the outside of the coated product so that it can be electrified. It can be of any color, with white particularly common in the United States so that the fencing is visible to livestock. Most forms can be installed on either wood posts or steel t-posts.
A variant, sometimes called "vinyl rail" or "strap fencing" consists of two or more vinyl-encased wires with vinyl or other synthetic between them to create a "rail" that is anywhere from 1 to 10 centimetres (0 to 4 in) wide. Some forms may be electrified by use of a special coating on the top wire of the "rail."
Vinyl fence is installed in a manner similar to plain high-tensile fence and must be stretched tight. Strong bracing of posts at corners and in the middle of long fencelines is required. Like other wire fences, keeping vinyl fencing tightened on a regular basis is key to safety and appearance.
A mesh form of vinyl fencing without internal wires is marketed as "deer fence" and used in some locations to augment other fencing to keep out wild animals. There are also some forms of vinyl fencing that look similar to vinyl-coated wire, but do not contain an internal wire, that are marketed to livestock owners. They are marketed as particularly safe, but their strength in containing animals is under debate. These products are very new to the market.
[edit]Wood, pipe and other materials
A pipe fence is very strong and will not break
Fences of wood, stranded cable, and pipe are used where cost is less of a consideration, particularly on horse farms, or in pens or corrals where livestock are likely to challenge the fence. Synthetic materials with wood-like qualities are also used, though they are the most expensive option in most situations. In some areas, these types of fencing materials can be cost-effective if plentiful. For example, scrap pipe is often easily obtained at a low price if oil fields are nearby, and wooden rails can sometimes be harvested from the owner's own land if it contains suitable standing timber.
Fladry lines, made of cloth, metal and/or other materials, are sometimes used on fences to discourage predators from entering a livestock enclosure.
[edit]Maintenance
All types of agricultural fencing require regular maintenance to ensure their effectiveness. Cattle and horses are strong enough to go through most types of fence by main force, and occasionally do so when frightened or motivated by hunger, thirst, or sex drive. Weather, flood, fire, and damage from vandals or motor vehicle accidents can do similar damage and may allow livestock to escape. |
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The State Barrier Fence of Western Australia, [1] formerly known as the No. 1 Rabbit-proof Fence, the State Vermin Fence and the Emu Fence, is a pest-exclusion fence constructed between 1901 and 1907 to keep rabbits and other agricultural pests, from the east, out of Western Australian pastoral areas.
There are three fences in Western Australia: the original No. 1 Fence, which crosses the state from north to south, the No. 2 Fence which is smaller and further west, and the smaller east-west running No. 3 fence. The fences took six years to build. When completed in 1907, the Rabbit-Proof Fence (including all three fences) stretched 2, 021 miles (3, 253 km). The cost to build the fences at the time was £337, 841.
Contents [hide]
1 Construction
2 Maintenance
3 Cultural references
4 Outside of WA
5 See also
6 References
7 Bibliography
8 External links
[edit]Construction
The fence posts are placed 12 feet (3.7 m) apart, and have a minimum diameter of 4 inches (10 cm). There were initially three wires of 12½ gauge placed at 4 inches (10 cm), 20 inches (51 cm), and 3 feet (91 cm) above ground, with a barbed wire added later at 3'4" and a plain wire at 3'7" to make the fence a barrier for dingoes and foxes as well. Wire netting was placed on this, which extended to 6 inches (15 cm) below ground.
The fence was constructed with different materials due to the local climate, and availability of wood. At first salmon gum and gimlet wood were used, although these attracted white ants and had to be replaced. Split white gum was one of the best types of wood used in the fence. Others used were mulga, wodjil, pine, and Tea tree, based on where it could be found close to where the fence was to be built. Iron was used in parts where there was no wood.
[edit]Maintenance
Boundary rider’s team at the 100-mile (160 km) No. 1 fence in Western Australia in 1926
Alexander Crawford (Inspector of rabbits), took over the maintenance of the fence from Anketell when the fence was finished in 1907 and remained in charge until he retired in 1922. He was eventually appointed Chief Inspector of Rabbits. The area inside the fence to the west became known as "Crawford's Paddock". The fence was maintained at first by boundary riders riding bicycles, and later by riders astride camels. However, fence inspection was difficult from atop the tall animal. In 1910 a car was bought for fence inspection, but was subject to punctured tyres. It was found the best way to inspect the fence was using buckboard buggies, pulled by two camels.
The camels were used as pack animals, especially in the north, while in the south, camels were used to pull drays with supplies for the riders. Camels were ideal for this as they could go for a long time without water, and it has been suggested that the fence could not have been built or maintained without the use of camels.
In addition to Crawford, there were four sub-inspectors, each responsible for about 800 kilometres (500 mi) of fence, and twenty-five boundary riders who regularly patrolled 160 kilometres (99 mi) sections of fence. Due to frontier violence in the north of the state, a 500 kilometres (310 mi) section of the No.1 fence was patrolled by riders in pairs.[2]
Crawford was responsible for eliminating rabbits which had breached the fence. In the first year following the completion of the fences, colonies were found and destroyed near several locations inside the fence, including Coorow, Mullewa and Northampton.[2]
Following the introduction of Myxomatosis to control rabbits in the 1950s, the importance of the Rabbit Proof Fence diminished.
[edit]Cultural references
Map of the original rabbit-proof fences in Western Australia.
In 1929, Arthur Upfield, an Australian writer, began writing a fictional story which involved a way of disposing of a body in the desert. He had previously worked on the construction of the No. 1 fence. Before the book was published, stockman Snowy Rowles, an acquaintance of the writer, carried out at least two murders and disposed of the bodies in the method described in the book. The trial which followed in 1932 was one of the most sensational in the history of Western Australia. A book was published about the incident called Murder on the Rabbit Proof Fence: The Strange Case of Arthur Upfield and Snowy Rowles.[3] The incident is now referred to as The Murchison Murders.
In the book Follow the Rabbit-Proof Fence by Doris Pilkington Garimara, the fence was used in the 1930s by three Indigenous Australian girls for their route back home to Jigalong. The girls, taken from their parents in Western Australia as part of the Stolen Generation, escaped from the Moore River Native Settlement mission where they were being held and walked back to their family at Jigalong by following the rabbit-proof fence. The book was made into a film in 2002.
[edit]Outside of WA
A fourth rabbit fence crosses Queensland.[4] only two out of the three girls who followed the fence after escaping captivity, made it back to their family. |
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Temporary Fence is used where building a permanent fence is either impractical or unneeded. Temporary fencing is used when an area needs barriers for the purposes of public safety or security, crowd control, theft deterrent, or equipment storage. Its most common use is as construction hoarding for security fencing around building sites. Other uses for temporary fencing include venue division at large events and public restriction on industrial construction sites. Temporary fencing is also often seen at special outdoor events, parking lots, and emergency/disaster relief sites.
Common forms of temporary fencing include a variety of plastic fencing or panels constructed of chainlink, steel or wire. Fencing commonly consists of individual panels that can be set up around the perimeter of the desired area to be fenced in.
[edit]Legal requirements
Many federal and/or state laws require building contractors to protect the public from the hazards associated with building and construction sites. These laws often expressly require the use of temporary fencing. In the US, occupational safety and health laws are policed by the Occupational Safety and Health Administration (OSHA).
Temporary fencing is often required to meet safety standards set by Government authorities and meet strict engineering requirements such as wind force resistance. In Australia temporary fencing must meet the Australian Standards AS 4687 - 2007.
[edit]Legal compliance
Depending on occupational safety requirements in any given country or region, the quality of temporary fencing used on building and construction sites can be examined by government inspectors.
Builders can be prosecuted for not protecting the general public from construction site hazards and/or can be issued on the spot fines for a non compliant temporary fencing system. |
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A split-rail fence or log fence is a type of fence constructed out of timber logs, usually split lengthwise into rails and typically used for agricultural or decorative fencing. Such fences require much more timber than other types of fences, and so are generally only common in areas where wood is abundant. However, they are very simple in their construction, and can be assembled with few tools even on hard or rocky ground. They also can be built without using any nails or other hardware; such hardware was often scarce in frontier areas. They are particularly popular in very rocky areas where post hole digging is almost impossible.They can even be partially or wholly disassembled if the fence needs to be moved or the wood becomes more useful for other purposes. During the American Civil War, these split rail fences were a major source of firewood for both the Union and Confederate armies.
Log fence with double posts (photo taken in 1938).
Split rail fences were made of easy to split, rot-resistant wood. Traditionally American chestnut was the timber of choice until chestnut blight eliminated this tree. Currently, most split rails are made from cedar.[clarification needed] Whether of chestnut or cedar, these logs were cut to a length of 10 to 12 feet (3.0 to 3.7 m) and split down the length of the log. Each half was then split into quarters, then eighths and so on until the rails were of a usable size. A log may produce from four rails from an 8-inch (20 cm) log to over a dozen from larger logs. The rails are stacked on top of one another. Most split rail fences have the rails stacked in an interlocking zig-zag fashion that is self-supporting, easy to create, easy to repair, and easy to disassemble.
A split-rail fence with supports.
Some timber fences have the rails stacked directly on top of each other and secured with double fence posts (one on either side of the rails). This made a more permanent and compact fence but remained easy to repair.
The distance between either the zigs or the zags is generally 16.5 feet (5 m) or one rod. The area of a field can therefore be calculated by counting zigs or zags along the side and end of the field: one hundred sixty square rods is 1-acre (0.40 ha).
A mortised split-rail fence in suburban America (built 1999).
[edit]Mortised fence
In the United Kingdom (and increasingly in suburban America) a different style of split-rail fence is used. This is not free-standing but consists of vertical posts placed in the ground, having holes (mortises) in each side into which the roughly pointed ends of split rails (usually of sweet chestnut) are placed. No zig-zagging is necessary. This style is commonly used as decorative fencing, or for horse-keeping. |
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An electric fence is a barrier that uses electric shocks to deter animals or people from crossing a boundary. The voltage of the shock may have effects ranging from uncomfortable, to painful or even lethal. Most electric fencing is used today for agricultural fencing and other forms of animal control purposes, though it is frequently used to enhance security of sensitive areas, and there exist places where lethal voltages are used.
Contents [hide]
1 Design and function
1.1 Fence energizers
1.2 Fencing materials
2 History
3 Uses
3.1 Agriculture
3.2 Wild animals
3.3 Security
3.3.1 Non-lethal fence
3.3.2 Lethal fence
3.4 Other uses
4 Interference and unwanted effects
5 See also
6 References
7 External links
[edit]Design and function
Detail of an electric fence material made of synthetic cord with metal interwoven through it, attached to a steel fence post with a plastic insulator. This material is more visible than wire, but most often used for temporary fencing.
Electric fences are designed to create an electrical circuit when touched by a person or animal. A component called a power energizer converts power into a brief high voltage pulse. One terminal of the power energizer releases an electrical pulse along a connected bare wire about once per second. Another terminal is connected to a metal rod implanted in the earth, called a ground or earth rod. A person or animal touching both the wire and the earth during a pulse will complete an electrical circuit and will conduct the pulse, causing an uncomfortable electric shock. The effects of the shock depend upon the voltage, the energy of the pulse, the degree of contact between the recipient and the fence and ground and the route of the current through the body; it can range from barely noticeable to uncomfortable, painful or for some fences even lethal.
[edit]Fence energizers
Early alternating current (AC) fence chargers used a transformer and a mechanically-driven switch to generate the electrical pulses. The pulses were wide and the voltage unpredictable, with no-load peaks in excess of 10, 000 volts and a rapid drop in voltage as the fence leakage increased. The switch mechanism was prone to failure. Later systems replaced the switch with a solid-state circuit, with an improvement in longevity but no change in pulse width or voltage control.
"Weed burner" fence chargers were popular for a time and featured a longer-duration output pulse that would destroy weeds touching the fence. These were responsible for many grass fires when used during dry weather. Though still available, they have declined in popularity.
Modern "low impedance" fence chargers use a different design. A capacitor is charged by a solid-state circuit – upon contact with a grounded animal or person, the charge is then released using a thyristor or similar solid-state component. Voltage is consistent due to electronic output controls, within the limits of output power. Pulse width is much narrower, often about 10 microseconds. This design works for either battery or mains power sources.
Depending on the area to be fenced and remoteness of its location, fence energizers may be hooked into a permanent electrical circuit, may be run by lead-acid or dry cell batteries, or a smaller battery kept charged by a solar panel. The power consumption of a fence in good condition is low, and so a lead-acid battery powering several hundred metres of fence may last for several weeks on a single charge. For shorter periods dry cell batteries may be used. Some energizers are capable of being powered by more than one source.
[edit]Fencing materials
Smooth steel wire is the material most often used for electric fence, ranging from a fine thin wire used as a single line to thicker, high-tensile (HT) wire. Less often, woven wire or barbed wire fences can be electrified, though such practices create a more hazardous fence, particularly if a person or animal becomes caught by the fencing material (electrified barbed wire is illegal in some areas). Synthetic webbing and rope-like fencing materials woven with fine conducting wires (usually of stainless steel) have become available the last 15 to 20 years, and are particularly useful for areas requiring additional visibility or as temporary fencing.
The electrified fence itself must be kept insulated from the earth and from any materials that will conduct electricity and ignite or short out the fence. Fencing must therefore avoid vegetation, and cannot be attached directly to wood or metal posts. Typically, wooden or metal posts are driven into the ground and plastic or porcelain insulators are attached to them, or plastic posts are used. The conducting material is then attached to the posts.
[edit]History
This section needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (October 2008)
Jules Verne's "20, 000 Leagues Under the Sea", described [1] the use of electrification of a structure as a defensive weapon, in 1870. The concept of the electric fence was first described in Mark Twain's A Connecticut Yankee in King Arthur's Court, in 1889, as a defensive weapon. Electric fences were used to control livestock in the United States in the early 1930s, and electric fencing technology developed in both the United States and New Zealand. It was also mentioned in
An early application of the electric fence was developed in 1936–1937 by New Zealand inventor William "Bill" Gallagher Sr. Built from a car's ignition coil and a magneto set, Gallagher used the device to keep his horse from scratching itself against his car. Gallagher later started a company to improve and market the design.[2] In 1962, another New Zealand inventor, Doug Phillips, invented the non-shortable electric fence based on capacitor discharge. This significantly increased the range an electric fence could be used from a few hundred meters to 20km (~35 miles), and reduced the cost of fencing by more than 80%.[citation needed] The non-shortable electric fence was patented by Phillips and by 1964 was manufactured by Plastic Products, a New Zealand firm, under the name "Waikato Electric Fence."[citation needed] This idea was to replace ceramic with plastic insulators. A variety of plastic insulators are now used on farms throughout the world today.
In 1969 Robert B. Cox, a farmer in Adams County, Iowa, invented an improved electric fence bracket and was issued United States Patent No. 3, 516, 643 on June 23, 1970. This bracket improved electric fences by keeping the wire high enough above the ground and far enough away from the fence to permit grass and weeds growing beneath the wire to be mowed. The brackets attached to the posts by what may be called a "pivot bind" or "torsion-lock." The weight of the bracket, the attached insulator and the electric wire attached to the insulator bind the bracket to the post.
Electric fences have improved significantly over the years. Improvements include:
Polyethylene insulators replacing porcelain insulators, beginning in the 1960s. Polyethylene is much cheaper than porcelain and is less breakable.
Improvements in electrical design of the fence energizer, often called a "charger" (USA) or "fencer" (UK).
Changes in laws. In some jurisdictions, certain types of electrical outputs for fences were unlawful until the 1950s or 1960s. In other areas, signage requirements and other restrictions limited usability. Many US cities continue to have outdated laws prohibiting electric fences to prevent agricultural fences from entering the city. Houston, for example, changed their ordinance that prohibited electric fencing in 2008.[3]
Introduction of high tensile (HT) steel fence wire in the 1970s in New Zealand and in the 1980s in the United States
Introduction of synthetic webbing and rope-like fencing materials woven with fine conducting wires.
Design of moveable fence components, such as Tumblewheel.
[edit]Uses
[edit]Agriculture
Main article: Agricultural fencing
Permanent electric fencing is used in many agricultural areas, as construction of electric fences can be much cheaper and faster than conventional fences (it uses plain wire and much lighter construction, as the fence does not need to physically restrain animals). The risk of injury to livestock (particularly horses) is lower compared to fences made of barbed wire or certain types of woven wire with large openings that can entangle the feet.
Its disadvantages include the potential for the entire fence to be disabled due to a break in the conducting wire, shorting out if the conducting wire contacts any non-electrified that may make up the rest of the fence, power failure, or forced disconnection due to the risk of fires starting by dry vegetation touching an electrified wire. Other disadvantages can be lack of visibility and the potential to shock an unsuspecting human passer-by who might accidentally touch or brush the fence.
Many fences are made entirely of standard smooth or high-tensile wire, though high quality synthetic fencing materials are also beginning to be used as part of permanent fences, particularly when visibility of the fence is a concern.
Conventional agricultural fencing of any type may be strengthened by the addition of a single electric line mounted on insulators attached to the top or front of the fence. A similar wire mounted close to the ground may be used to prevent pigs from excavating beneath other fencing. Substandard conventional fencing can also be made temporarily usable until proper repairs are made by the addition of a single electric line set on a "stand-off" insulator.
A temporary electric fence of synthetic materials and plastic step-in posts set about 12 feet apart
Electric materials are also used for the construction of temporary fencing, particularly to support the practice of managed intensive grazing (also known as rotational or "strip" grazing). It is also popular in some places for confining horses and pack animals overnight when trail riding, hunting, or at competitions such as endurance riding and competitive trail riding. Typically, one or more strands of wire, synthetic tape or cord are mounted on metal or plastic posts with stakes at the bottom, designed to be driven into the ground by foot. For a hand-tightened temporary fence of electrified rope or web in a small area, these are usually spaced at no more than 12 to 15 feet (about 3 metres) to prevent the fencing material from sagging and touching the ground. Larger areas where tools are used to stretch wire may be able to set step-in posts at larger distances without risk that the fencing material will sag.
With temporary electric fencing, a large area can be fenced off in a short period of time. Temporary fencing that is intended to be left in place for several weeks or months may be given additional support by the use of steel T posts (which are quickly pounded in with hand tools and unearthed with relative ease using a leverage device) to help keep the fence upright, particularly at corners. Livestock owners using rotational grazing in set patterns that are similar from one year to the next may permanently drive a few permanent wood fence posts in strategic locations.
Portable fence energizers are made for temporary fencing, powered solely by batteries, or by a battery kept charged by a small solar panel. Rapid laying-out and removal of multiple-strand temporary electric fencing over a large area may be done using a set of reels mounted on a tractor or all-terrain vehicle.
For sheep, poultry, and other smaller animals, plastic electric netting may be mounted on insulating stakes – this is also effective at keeping out some predators such as foxes.
In practice, once most animals have learned of the unpleasant consequences of touching the fence they tend to avoid it for considerable periods even when it is inactive. However, some animals learn to avoid the shock, either by running under the fence quickly between pulses, or by pushing other individuals through the fence. Animals with thick woolly coats (such as sheep or Highland cattle) may learn to push through the fence themselves, using their coats as electrical insulation. Some animals also learn to recognize the slight clicking sound made by some electric fences and thus can sense when the fence is off.
[edit]Wild animals
Electric fencing to protect a walkway against wildlife. Pilanesberg Game Reserve, South Africa
Electric fences are useful for controlling the movements of wild animals. Examples include deterring deer from entering private property, keeping animals off airport runways, keeping wild boar from raiding crops, and preventing geese from soiling areas used by people. Electric fencing has been extensively used in environmental situations reducing the conflict between elephants or other animals and humans in Africa and Asia.
[edit]Security
Electric fencing at an airport
[edit]Non-lethal fence
Non-lethal electric fences are used to prevent trespass by both private and government-sector bodies. These include freight carriers, auto auctions, equipment rental companies, auto dealers, housing communities, commercial factories or warehouses, prisons, military bases, and government buildings. Many of these electric fences act as monitored burglar alarm systems in addition to causing an uncomfortable shock. Electric fences are occasionally employed to discourage suicide attempts on tall structures, and to reduce the incidence of graffiti and other petty crime.
[edit]Lethal fence
Electric fences designed to carry potentially lethal currents can be used for anti-personnel purposes.
In 1915, during World War I, the German occupiers of Belgium closed off the border with neutral Netherlands, using a 300 km electric fence running from Vaals to Scheldt. Germany also erected a similar fence to isolate thirteen Alsatian villages from Switzerland.[4]
Electric fences were used to guard the concentration camps of Nazi Germany during World War II, where potentially lethal voltages and currents were employed, continuously rather than in pulses. Some prisoners used the electric barbed wire fence to commit suicide.[5]
During the Algerian War the French erected the electrified Morice Line.
Sections of the inner German border were lined with a 3 m (10 ft) high electric fence to stop potential defectors from East Germany.[6]
They continue to be used in similar fashion at some high-security prisons and certain other installations to this day. Typically a nonelectric fence is constructed on either side of such an installation, or the deadly current is carried out of casual reach atop a wall.[citation needed]
North Korea uses electric fences to seal off parts of its border with South Korea.
[edit]Other uses
Recent innovations include electrical fence monitoring for intruder detection as opposed to providing an electric shock to discourage entry. It can be used in addition to or as substitute for a host of other fence monitoring systems.
Buried electric fences (also called "invisible fences" or "electronic fences") are sometimes used to contain dogs or livestock. The buried wire radiates a weak radio signal, which is detected by a collar worn by the animal. The collar emits a warning noise near the wire, but if this is ignored, produces a mild shock. Humans and other animals are unaware of the buried line. In a similar system, the collar uses GPS signals to determine proximity to a predetermined "virtual fence" without a physical installation.
[edit]Interference and unwanted effects
Poorly maintained electric fences (with insufficient grounding or bad design) can interfere with, and significantly degrade, the performance of nearby telephone and data connections, along with radio and television reception[citation needed]. |
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A chain-link fence (also referred to as wire netting, chain-wire fence, cyclone fence or hurricane fence) is a type of woven fence usually made from galvanized or LLDPE-coated steel wire. The wires run vertically and are bent into a zig-zag pattern so that each "zig" hooks with the wire immediately on one side and each "zag" with the wire immediately on the other. This forms the characteristic diamond pattern seen in this type of fence.
Contents [hide]
1 Sizes and uses
2 Installation
3 Development of chain-link fencing
4 Notable uses
5 See also
6 Notes
7 External links
[edit]Sizes and uses
In the United States, fencing usually comes in 20 rod and 50 ft rolls which can be joined by "unscrewing" one of the end wires and then "screwing" it back in so that it hooks both pieces. Common heights include 3 ft, 3 ft 6 in, 4 ft, 5 ft, 6 ft, 7 ft, 8 ft, 10 ft, and 12 ft, though almost any height is possible. Common mesh gauges are 9, 11, and 11.5. For tennis courts and ball parks the most popular height is 10 ft.
The popularity of chain-link fence is due to its relatively low cost and ease of installation. A further advantage is that due to the open weave, chain-link fences are transparent, and do not obscure sunlight from either side of the fence. If a semi-opaque fence is desired, this can be achieved by the insertion of slats into the mesh.
[edit]Installation
The installation of chain-link fence involves setting posts into the ground and attaching the fence to them. The posts may be steel tubing, timber or concrete and may be driven into the ground or set in concrete (preferably both). End, corner or gate posts, commonly referred to as 'terminal posts', must either be set in concrete footing or otherwise anchored to prevent leaning under the tension of a stretched fence. Posts set between the terminal posts are called line posts and are set in concrete footings (or in some locations driven in place) at intervals not to exceed 10 feet. The fence is attached at one end, stretched, and attached at the other, the excess being easily removed by "unscrewing" a wire. Finally it is tied to the line posts with aluminum wire. In many cases a bottom tension wire, sometimes referred to as coil wire, may be stretched between terminal posts to help minimize the in and out movement that occurs at the bottom of the chain-link mesh between posts. Once stretched, this wire should be secured to the line posts and the chain-link mesh "hog ringed" to the tension wire 2' on center. The installation of this wire is generally done prior to the installation of the chain-link mesh.
[edit]Development of chain-link fencing
A chain-link privacy fence topped with razor wire protecting a utility power sub-station.
In the United Kingdom the firm of Barnard, Bishop & Barnard was established in Norwich to produce chain-link fencing by machine. The process was developed by Charles Barnard in 1844 based on cloth weaving machines (up until that time Norwich had a long history of cloth manufacture).[1]
Anchor Fence (established in 1891) was the first US company to manufacture chain-link fencing by machines using equipment imported from Belgium.
[edit]Notable uses
Chain-link fencing at an American short track
Used to notable effect in the Gehry Residence by Frank Gehry
Wrestling steel cage matches
Backstops used in baseball and softball fields
Before the advent of gravel trap in the later half of the 1980s, chain-link fencing was used as catch fences in racetracks to slow out-of-control cars down before they impact barriers. In the 2000s they continued to be used at American dirt tracks. |
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