Tuesday 23 October 2012
The original
The originator of the original Rollgliss system, Mr Wullimann (Pictured). The Rollgliss R300 was made at Galvano Wullimann AG a metal
fabricators in Selzach, Switzerland and now under licence in Germany where the
R300 version is still made under the trade name of SWISS RESCUE®. The
standard rope for European use was 3/8" or 9mm although a larger diameter rope
and adapted Rollgliss was made available for use in the USA. Rollgliss sold the
patent for the Rollgliss R350 and the trade name to Protecta Ltd, now part of
Capital Safety Ltd. Specialist Training Consultants Ltd have been associated
with the supply and maintenance of Rollgliss since our formation in 1997 and
have been an operational user since 1988. We work closely with the manufacturer
and are recognised as the principle service agent here in the UK for the entire
range of Rollgliss equipment.
Monday 22 October 2012
Keep up with us!
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Ground pins
Used in firm ground the Ground pin set can provide additional anchorage points in wide range of remote environments. The basic kit contains 6 pins and a heavy hammer in a carry bag.
Positioned in crescent shape with at least 1m between the pins. The individual Galvanised steel pins should be inserted to full length 600mm and inclined slightly backwards. The pins which are 22mm diameter galvanised mild steel allow for a variety of attachments. Rope can be directly knotted or connected through a lanyard and connector.
The rope layout can be a fixed belay or self equalising. It is important as with all anchorages to monitor the parts for movement and of course avoid shock loads. In soft ground pins have been used "in line" one behind another to further strengthen the anchorage. Removing the pins is easy, as by a simple twisting action they can be pulled free from the ground. We have chalk cliffs near to us at STC and have inserted these pins through the top soil into the chalk beneath to provide a very strong anchor point
A closer picture of the individual pin, connected into a belay system via a short protected lanyard. The picture shows a large Klettersteig karabiner, another option would be to use a delta maillon.
Positioned in crescent shape with at least 1m between the pins. The individual Galvanised steel pins should be inserted to full length 600mm and inclined slightly backwards. The pins which are 22mm diameter galvanised mild steel allow for a variety of attachments. Rope can be directly knotted or connected through a lanyard and connector. The rope layout can be a fixed belay or self equalising. It is important as with all anchorages to monitor the parts for movement and of course avoid shock loads. In soft ground pins have been used "in line" one behind another to further strengthen the anchorage. Removing the pins is easy, as by a simple twisting action they can be pulled free from the ground. We have chalk cliffs near to us at STC and have inserted these pins through the top soil into the chalk beneath to provide a very strong anchor point A closer picture of the individual pin, connected into a belay system via a short protected lanyard. The picture shows a large Klettersteig karabiner, another option would be to use a delta maillon.
Hardware part 1
First of all, is it karabiner or carabiner, after a day on the ropes and
over a few beers this one can go on forever! I have over the years read, heard
and discussed every argument, statement and fact. The vast majority will call
this piece of bent metal a carabiner, for me it’s a karabiner. The bottom line
is that what ever you call it, the thing must be appropriate for your task
without compromising safety.
Aluminium or steel, which is best? That depends on your application. If you were an Alpine climber, racked out with lots of kit, including 30+ karabiners, then you would appreciate the weight involved and opt without question for aluminium. For rescue and industrial applications you will find yourself on the other side of the fence, steel being your principal choice. Just to confuse the whole issue, climber or rescuer you will have use for both.
Most aluminium karabiners are forged into their desired shape, then heat treated to arrange the molecules like the grain in hard wood. It’s in these aluminium karabiners that we see the most variation in shape, being designed primarily for the sports climbing market (ref:pic 1).
Pic 1
I read a hefty
article about the metallurgy of aluminium karabiners, and the one thing that I
clearly remember is that the material, when being forged, takes on a crystalline
structure, immensely strong but it can be brittle. So what happens if one is
dropped from a height onto a hard surface? Aluminium karabiners do not “witness
damage” very well, in other words it will look fine, until it is shock loaded
whereupon it may fracture and fail with disastrous results. To get round this
problem, if you drop it, bin it! A steel karabiner, if dropped, will invariably
be visibly marked and thus will “witness damage”, also steel karabiners will
distort out of shape if over loaded. So don’t panic, failure of karabiners is
virtually unheard of, it’s the failure of the user, that is the point to watch
out for!
Regardless of construction material, all karabiners used in rescue should have a breaking strain of at least 28kN for aluminium (ref:pic 2)
Pic 2
and 42kN for steel (ref:pic 3), in addition they should all have spring loaded gates with screw locks. I am never comfortable with twist lock gates, however for industrial users or occasional users I do recommend them. Some manufacturers offer a twist lock with an independent lock system, push button or pull and twist options. (ref:pic 4) these are excellent.
Pic 3
Pic 4
For the vast amount of applications my own preference is a large steel screw gate karabiner that is rated at 42kN, made by DMM in North Wales. UK. (ref pic 5)
Pic 5
Corrosion will always be worth looking out for (ref:pic 6). Steel (Iron and Carbon) used in the manufacture of Karabiners is an alloy that may include Sulphur, Manganese and Phosphorous. Karabiners are then plated with a process that puts several layers on the surface. As the top layer is worn away by abrasion or friction the remaining layers will keep corrosion under control. Aluminium karabiners are made from an alloy containing Aluminium, Magnesium and Silica that has good corrosion resisting properties and most are also anodised. Corrosion, either rust on steel components or oxides from aluminium, (we have all rubbed down wood with aluminium oxide paper) will not do our lines or webbing kit any good if it is allowed to build up. Surprisingly the one item left off most kit lists is a washing machine or at least access to one for our ropes and slings etc.
Pic 6
I had an
interesting conversation with a representative of the Health and Safety
Executive on the for’s and against’s regarding karabiners and was intrigued to
hear that the HSE would prefer the use of Maillon Rapides in most applications
as they have an unparallelled safety record. I tried it and liked it, used as the
item of choice by many Police tactical teams; Maillons will be used without
exception when rigging. They now form part of my standard kit and I have found
myself recommending them more and more. Delta Maillon (triangle shape) or Pear
shaped (ref: pic 7) in 10mm stainless steel, they are certificated as
PPE and have an EN reference number.
Pic 7.
Being able to take
a load on three axes against only two for a karabiner, they are perfect for use
when rigging or establishing anchor points (ref: pic 8). Secured finger
tight or nipped up with a 13mm spanner or a multi tool, they have a 100% safety
record.
When used appropriately they will be superior to a Karabiner, but I must add never replace them, both Karabiners and Maillons will be found in my kit.
Pic 8.
We clean harness, lines, and tapes but often disregard
Karabiners assuming they can look after themselves. Hinges and springs become
clogged with dirt and threads on screw gates become stiff with dirt. A good
scrub in warm soapy water, a toothbrush to clean threads and hinges comes in
handy. The most positive part is handling and taking a close look at this
often-neglected item. I once witnessed Karabiners being lubricated with WD40!
Shock and horror, the oil will accumulate more dirt while the solvent base will
contaminate lines and tapes slowly destroying their molecular structure! A good
Karabiner that is clean and dry will need nothing or at most a touch of Silicon
spray on the hinge and thread.
The bottom line is; if you are in any doubt about the integrity of your Karabiners be they Steel or Aluminium then retire them, they are a cheap item, but crucial to any line rescue system.
Aluminium or steel, which is best? That depends on your application. If you were an Alpine climber, racked out with lots of kit, including 30+ karabiners, then you would appreciate the weight involved and opt without question for aluminium. For rescue and industrial applications you will find yourself on the other side of the fence, steel being your principal choice. Just to confuse the whole issue, climber or rescuer you will have use for both.
Most aluminium karabiners are forged into their desired shape, then heat treated to arrange the molecules like the grain in hard wood. It’s in these aluminium karabiners that we see the most variation in shape, being designed primarily for the sports climbing market (ref:pic 1).
Pic 1
I read a hefty
article about the metallurgy of aluminium karabiners, and the one thing that I
clearly remember is that the material, when being forged, takes on a crystalline
structure, immensely strong but it can be brittle. So what happens if one is
dropped from a height onto a hard surface? Aluminium karabiners do not “witness
damage” very well, in other words it will look fine, until it is shock loaded
whereupon it may fracture and fail with disastrous results. To get round this
problem, if you drop it, bin it! A steel karabiner, if dropped, will invariably
be visibly marked and thus will “witness damage”, also steel karabiners will
distort out of shape if over loaded. So don’t panic, failure of karabiners is
virtually unheard of, it’s the failure of the user, that is the point to watch
out for! Regardless of construction material, all karabiners used in rescue should have a breaking strain of at least 28kN for aluminium (ref:pic 2)
Pic 2
and 42kN for steel (ref:pic 3), in addition they should all have spring loaded gates with screw locks. I am never comfortable with twist lock gates, however for industrial users or occasional users I do recommend them. Some manufacturers offer a twist lock with an independent lock system, push button or pull and twist options. (ref:pic 4) these are excellent.
Pic 3
Pic 4
For the vast amount of applications my own preference is a large steel screw gate karabiner that is rated at 42kN, made by DMM in North Wales. UK. (ref pic 5)
Pic 5
Corrosion will always be worth looking out for (ref:pic 6). Steel (Iron and Carbon) used in the manufacture of Karabiners is an alloy that may include Sulphur, Manganese and Phosphorous. Karabiners are then plated with a process that puts several layers on the surface. As the top layer is worn away by abrasion or friction the remaining layers will keep corrosion under control. Aluminium karabiners are made from an alloy containing Aluminium, Magnesium and Silica that has good corrosion resisting properties and most are also anodised. Corrosion, either rust on steel components or oxides from aluminium, (we have all rubbed down wood with aluminium oxide paper) will not do our lines or webbing kit any good if it is allowed to build up. Surprisingly the one item left off most kit lists is a washing machine or at least access to one for our ropes and slings etc.
Pic 6
I had an
interesting conversation with a representative of the Health and Safety
Executive on the for’s and against’s regarding karabiners and was intrigued to
hear that the HSE would prefer the use of Maillon Rapides in most applications
as they have an unparallelled safety record. I tried it and liked it, used as the
item of choice by many Police tactical teams; Maillons will be used without
exception when rigging. They now form part of my standard kit and I have found
myself recommending them more and more. Delta Maillon (triangle shape) or Pear
shaped (ref: pic 7) in 10mm stainless steel, they are certificated as
PPE and have an EN reference number. Pic 7.
Being able to take
a load on three axes against only two for a karabiner, they are perfect for use
when rigging or establishing anchor points (ref: pic 8). Secured finger
tight or nipped up with a 13mm spanner or a multi tool, they have a 100% safety
record. When used appropriately they will be superior to a Karabiner, but I must add never replace them, both Karabiners and Maillons will be found in my kit.
Pic 8.
We clean harness, lines, and tapes but often disregard
Karabiners assuming they can look after themselves. Hinges and springs become
clogged with dirt and threads on screw gates become stiff with dirt. A good
scrub in warm soapy water, a toothbrush to clean threads and hinges comes in
handy. The most positive part is handling and taking a close look at this
often-neglected item. I once witnessed Karabiners being lubricated with WD40!
Shock and horror, the oil will accumulate more dirt while the solvent base will
contaminate lines and tapes slowly destroying their molecular structure! A good
Karabiner that is clean and dry will need nothing or at most a touch of Silicon
spray on the hinge and thread. The bottom line is; if you are in any doubt about the integrity of your Karabiners be they Steel or Aluminium then retire them, they are a cheap item, but crucial to any line rescue system.
A shocking tale
A lot of rope rescue technicians still don't understand the principles of fall
factor. However, it's quite simple, even if you hated arithmetic. Fall Factor is
simply the distance of the fall divided by the length of the rope or lanyard
from the person falling to anchor point.
The equation looks like this;
Fall Factor = Length of Fall / Length of Rope/lanyard
A Fall Factor 2 is the maximum you will encounter in a typical un-arrested fall, since the height of a fall can't exceed two times the length of the rope or lanyard. Normally, a Fall Factor 2 can only occur when a technician is working above his anchor point and at the maximum length of the rope or lanyard. The force is the same if you fall 2 metres or 20 metres.
Your well being depends on several factors, strength of your anchor, the stretch of the rope or deployment of the energy absorber, strength of your connectors and finally the fit of your harness.
Shock load is the result of three factors; the rope or energy absorber, the fall factor, and the weight of the falling object.
Obviously, the only part of this equation that can drastically reduce the force of a fall is the deployment of the energy absorber. So, safety systems are designed around the shock-absorbing quality of the energy absorber. It cushions the fall, reducing the impact force and the chance of system failure. The energy absorber is the one element in the whole system that is designed to limit the force of a rescue technicians’ weight in a worst-case fall (Fall Factor 2) to not more that 6 kN. The rest of the system can be designed to work with this known maximum force.
Static ropes are designed to minimise stretch. Their ability to absorb shock is marginal, particularly along short lengths of rope, and they transmit virtually all the shock load equally to the anchor system and to the body. In a rescue situation, a very short fall can develop enough force to be critical, especially with a casualty on board. Therefore rope of choice for rescue applications must be a semi static conforming to EN1891A and be of 11mm or 10.5mm in diameter. The compromise of the stretch will be very useful when arresting a fall and one thing often overlooked is the action of the various knots in the system to also tighten and absorb energy.
Webbing slings perform like static rope. Used for anchoring and extending a connection, slings are just as rigid as static rope. A Fall Factor 2 develops enough shock load to risk failure of the sling, the wearers harness, karabiners, not to mention damage to the rescue technicians internal organs.
In conclusion
A fall of less than four feet on a static rope or sling can create enough shock force to cause serious injury. The human body can only sustain, a shock force of 12 kN and loads of 18 kN are not only highly undesirable but very dangerous. In addition 18 kN is getting close to the minimum limits of all the items in your rope system. A fall factor 1.9 attached directly to a static rope running over a karabiner or pulley, with is normal shock force of 18 kN, becomes a shock force of 30 kN. Would your anchor hold? It is academic, because something else would undoubtedly fail.
Always ensure you’re protected by an energy absorber, protect yourself from falling by the use of restraint techniques or if safe to do so, use a fall arrest lanyard. Never work above your anchor point unless you are very well protected. Use only semi static ropes and ensure the equipment you use in the system is rated accordingly, e.g. sports climbing equipment has very limited use in rescue.
The most valuable item you carry is your brain, look at the problem and be sure you fully understand the consequences of your actions and results of an accidental arrested fall.
The equation looks like this;
Fall Factor = Length of Fall / Length of Rope/lanyard
A Fall Factor 2 is the maximum you will encounter in a typical un-arrested fall, since the height of a fall can't exceed two times the length of the rope or lanyard. Normally, a Fall Factor 2 can only occur when a technician is working above his anchor point and at the maximum length of the rope or lanyard. The force is the same if you fall 2 metres or 20 metres.
Your well being depends on several factors, strength of your anchor, the stretch of the rope or deployment of the energy absorber, strength of your connectors and finally the fit of your harness.
Shock load is the result of three factors; the rope or energy absorber, the fall factor, and the weight of the falling object.
Obviously, the only part of this equation that can drastically reduce the force of a fall is the deployment of the energy absorber. So, safety systems are designed around the shock-absorbing quality of the energy absorber. It cushions the fall, reducing the impact force and the chance of system failure. The energy absorber is the one element in the whole system that is designed to limit the force of a rescue technicians’ weight in a worst-case fall (Fall Factor 2) to not more that 6 kN. The rest of the system can be designed to work with this known maximum force.
Static ropes are designed to minimise stretch. Their ability to absorb shock is marginal, particularly along short lengths of rope, and they transmit virtually all the shock load equally to the anchor system and to the body. In a rescue situation, a very short fall can develop enough force to be critical, especially with a casualty on board. Therefore rope of choice for rescue applications must be a semi static conforming to EN1891A and be of 11mm or 10.5mm in diameter. The compromise of the stretch will be very useful when arresting a fall and one thing often overlooked is the action of the various knots in the system to also tighten and absorb energy.
Webbing slings perform like static rope. Used for anchoring and extending a connection, slings are just as rigid as static rope. A Fall Factor 2 develops enough shock load to risk failure of the sling, the wearers harness, karabiners, not to mention damage to the rescue technicians internal organs.
In conclusion
A fall of less than four feet on a static rope or sling can create enough shock force to cause serious injury. The human body can only sustain, a shock force of 12 kN and loads of 18 kN are not only highly undesirable but very dangerous. In addition 18 kN is getting close to the minimum limits of all the items in your rope system. A fall factor 1.9 attached directly to a static rope running over a karabiner or pulley, with is normal shock force of 18 kN, becomes a shock force of 30 kN. Would your anchor hold? It is academic, because something else would undoubtedly fail.
Always ensure you’re protected by an energy absorber, protect yourself from falling by the use of restraint techniques or if safe to do so, use a fall arrest lanyard. Never work above your anchor point unless you are very well protected. Use only semi static ropes and ensure the equipment you use in the system is rated accordingly, e.g. sports climbing equipment has very limited use in rescue.
The most valuable item you carry is your brain, look at the problem and be sure you fully understand the consequences of your actions and results of an accidental arrested fall.
Anchors, part 1
I have watched students tasked with attaching a line to a fixed anchor
point struggle and retie knots several times to achieve a slack fee connection.
Try this method and you will achieve results every time.
How much do I allow for the knot. Trial and error?
create a bight in the line (11mm) and pull the line and anchorage together tightly, adjusting the bight so that the two just meet. Note: the tighter these two are pulled together, the tighter will be the attachment.
Extend the bight an additional 8" or 200mm, as a guide, measure and use the span of your fingers as a guide. Then tie a figure of eight knot, dress and tension the knot in the normal manner.
Finally make the connection, you will find the knot to be in the perfect position. The system works with all lines, the length of the addition will need to be adjusted to accommodate different line diameters.
The major consideration in establishing any anchorage system is the prevention or at least the management of shock loads. These unwelcome forces can be caused by a number of reasons, whatever their cause they can seriously overload a system, causing the failure of knots and anchorages alike.
Prevention has always been better than cure. When a rope is under tension and then shock loaded we have relied in the past on the elasticity built into the line and the fact that knots will tighten slightly.
Energy dissipater
The energy dissipater has been around for a while, but like most items was designed for a different use. Petzl use a similar method of reducing shock loads in their Via ferrata lanyards, yet it has never been actively applied to rope terminations.
The rope in use, either an 11mm or even 9mm is passed through the holes in the device, it is very important to ensure that the correct sequence of holes is followed as they differ in size for the varying diameters of line. A diagram engraved on the body of the dissipater helps with this. Personally, for our lines that are packed and ready for use, we leave them in place. Most important is to leave a tail of about a metre and finish with a stop knot.
Under normal use, this termination is as secure as any knot. However should the rope be shock loaded the dissipater will allow the rope to pass through, absorbing energy in the process. The stop knot is a preventative measure to stop the rope from unravelling completely. Should you wish to prevent any movement in the rope pass the knotted tail beneath the last turn on the dissipater.
How much do I allow for the knot. Trial and error?
create a bight in the line (11mm) and pull the line and anchorage together tightly, adjusting the bight so that the two just meet. Note: the tighter these two are pulled together, the tighter will be the attachment.
Extend the bight an additional 8" or 200mm, as a guide, measure and use the span of your fingers as a guide. Then tie a figure of eight knot, dress and tension the knot in the normal manner.
Finally make the connection, you will find the knot to be in the perfect position. The system works with all lines, the length of the addition will need to be adjusted to accommodate different line diameters.
The major consideration in establishing any anchorage system is the prevention or at least the management of shock loads. These unwelcome forces can be caused by a number of reasons, whatever their cause they can seriously overload a system, causing the failure of knots and anchorages alike.
Prevention has always been better than cure. When a rope is under tension and then shock loaded we have relied in the past on the elasticity built into the line and the fact that knots will tighten slightly.
Energy dissipater
The energy dissipater has been around for a while, but like most items was designed for a different use. Petzl use a similar method of reducing shock loads in their Via ferrata lanyards, yet it has never been actively applied to rope terminations.
The rope in use, either an 11mm or even 9mm is passed through the holes in the device, it is very important to ensure that the correct sequence of holes is followed as they differ in size for the varying diameters of line. A diagram engraved on the body of the dissipater helps with this. Personally, for our lines that are packed and ready for use, we leave them in place. Most important is to leave a tail of about a metre and finish with a stop knot.
Under normal use, this termination is as secure as any knot. However should the rope be shock loaded the dissipater will allow the rope to pass through, absorbing energy in the process. The stop knot is a preventative measure to stop the rope from unravelling completely. Should you wish to prevent any movement in the rope pass the knotted tail beneath the last turn on the dissipater.
Ropes for rescue
It must be said that this single item of
equipment in my experience is the one that has little regard paid to it,
compared to other items of equipment. When new and fresh of the reel, its silky
feel and colours is something to behold, after a few uses, grubby and stuffed in
its bag its forgotten about until that next time its pulled out for use. It is
without question the most important part of the equipment that we shall use,
“line rescue” would just not exist if the line were missing. Over the years I
have used lines made from both natural and synthetic fibres, Hawser laid and
braided lines, everything from “Polyprop” to Kevlar (Aramid) tape.
Polyprop rope,
instantly recognisable as a blue three strand twisted rope. Found on Farms,
construction sites and working boats. It has two good characteristics, it floats
and its cheap! It has virtually no use in rope rescue. Also shown is
polyprop, in a braided version.
Is technology on top of rope construction or can we expect something radical? I think we now have the best that is available at this present time, manufactures of rope just don’t make for the rescue market, industrial users will always be the biggest consumers. But add together sports climbing with the need for specific lines together with top class sailing and we can see advances in rope design and construction that are filtering back into rescue rope manufacture.
Rope or Line? It’s like Carabiner or Karabiner? everyone has an opinion, so this is mine. I recall back in my early days as a young firefighter, being told by an individual who had worked with rope for all his life, that rope is the generic name of the manufacturedproduct . As soon as you cut it to a specific
length and designate it to a specific use, it becomes line: well, that’s good
enough for me. So to recap, manufacturers make rope and rescue technicians use
lines.
Choice of rope
The optimum rope for normal use is 11mm diameter nylon rope designed for rescue use. Strong enough to provide a good safety margin 3000Kg WLL, and be also sufficiently robust enough to withstand several years of use, providing you look after it. Weight is not such a concern, as it with sports climbing, there will always be helping hands to transport kit. This same rope must be suitable for all purposes (Controlled descent, safety line, establishing anchors and belays)
When
I first became involved in line rescue work, two types of line commonly were
used. An 11mm Static line for all descending/ascending and stretcher work (twin
line working was not common in those days) and finally a 9mm Dynamic line for
establishing belays. The latest lines using modern manufacturing techniques now
offer us lines that are sometimes termed low-stretch or industrial. These lines
are now the automatic choice for rescue professionals; the limited stretch makes
them ideal for all our applications. The Military/Law Enforcement and sports
cavers will still prefer the static lines, and for Sports climbers the 9mm
dynamic, for its ability to take a fall and its lightness.
For rescue work we now have the line that most suits our needs, the 11mm Semi static in working lengths up to 200m, 400m + are available, but these are monsters to handle and heavy to transport.
Special applications call for special ropes, most of my lines are 100m lengths, that for me is the all-round working rope length, not too heavy or bulky for a rope bag. However It is vitally important for any rescue team to assess the need for longer ropes, normally 200m is the longest commercially available. Longer lengths can be supplied but are special order and delivery times normally reflect this. Ropes of one continuous length can make life such a lot easier. The task of passing a knot or adding additional line during a descent can be time consuming and tiring for the rescuer.
Rope must be seen as a consumable, a new rope can be ruined first time it is used. You must be prepared for that, both emotionally and financially, believe me. A lot has been written regarding the working life of a line, in my experience lines in daily use will be worn out and require retiring long before they reach their age limit. For the record, 5 years of regular use seems to be the figure manufacturers have adopted. For rescue teams, up to 8 years is good for me. After all, the line is not being used every day and providing the line has never been shock loaded and is well maintained (as it should be, your life depends on it) it will be OK.
In my experience teams never buy long enough lengths and this failure generally proves expensive in the long term. As a supplier of equipment, including lines, it is more profitable for me to sell you two 50m lines than one 100m line. The longer has to be the most economic choice, its always the ends, sometimes the first 15-20m that will be worn the most. Even by rotating the line regularly, eventually they will have to be cut off, generally leaving a piece only 30m long, which is has very little practical use. However the 100m line can withstand having several ends cut off and still leave you with a good working line. I see this daily on the Rollgliss systems we overhaul, a too a short line was purchased initially and as only the running end that has been ruined, the entire line has to be replaced to maintain a good working length.
Transporting ropes
Ropes should always be stored and carried in rope bags. A well-designed bag, besides being far easier to stow and handle than hanked or coiled line, will protect the line from all kinds of damage. Coiled lines will tangle or develop kinks caused by twisting the rope, I like my lines to be packed tight in a hap-hazard fashion in the bag, reducing chaffing whilst in transit, my second choice is to 'chain a rope'. Finally the environment that we work in can be harsh, it makes much better sense to wear out the bag than damage a line. A line, which is dirty, is not only destroying itself but also your hardware. Even fine grit and dust, especially the oxides from aluminium equipment can rapidly wear out metal equipment and lines alike, and once embedded it is very difficult to subsequently remove all these particles from the rope.Lines like to be kept cool, dry and in the dark. I always keep my lines in their bags, damage from Sunlight or rather, ultra violet light will degrade the line, but this takes ages, the line will be worn out long before this type of damage becomes a concern. Most important is to ensure that lines are stored clean and dry.
After each operational use, lines must be inspected for damage and washed if necessary. Apart from normal surface abrasion which is more or less obvious, the worst thing that can happen to a line is contamination by chemicals, once identified and confirmed, the line or the contaminated end must be disposed off, you just cannot take that risk. Materials used in line construction are particularly stable polymers and are affected by very few common chemicals, however, it is well known that nylon is severely affected by even quite dilute acids, and that polyesters are attacked aggressively by strong alkali's.
Washing and inspection
Using a rope, which has become impregnated with grit, is also a recipe for disaster. Each time the rope is loaded over a pulley or squeezed through a descender a multitude of microscopic particles of grit and metal oxides are forcibly ground into the fragile yarn filaments of the kern and some weakening is inevitable. Thorough washing is important to remove as much as possible of this contamination that abrades the internal fibres of the line. A line cannot be properly inspected for any surface damage that may have occurred until it has been cleaned. Superficial dirt can be removed by simply sloshing the rope around in running water, avoid hosepipes or a Pressure washer, as these may force dirt into the core of the line.
For effective
cleaning, lines can be washed in a washing machine, normal wash temperature 40C.
Chaining the lines can prevent tangling. Other items, webbing or harness can be
stuffed it into a mesh wash bag. Adding normal amounts of a fabric softener is
useful and acceptable as it replaces the yarns normal Teflon / anti-static
lubricants that are used in the manufacturing process.
Regular machine washing is not harmful to the line, remember that the same fibre used in lines is that found in ordinary clothing, which is designed to be washed every few days. I always us a detergent, it helps the cleaning process, but look for PH neutral types, I have used soap flakes in the past but have been disappointed with the results. I also ensure the lines go through a full rinse cycle, which I feel is important.
Pictured is a
double jacket rope ( Orange over Black) laid over a four strand braided kern.
The double jackets give excellent wear characteristics but the two mantles
were prone to slippage. This is easily resolved by soaking the rope to induce
shrinkage and pulling the wet rope through a descender a few times whilst under
tension. Unfortunately many manufacturers have dropped this excellent
design.
After washing, lines should be carefully inspected for damage or signs of excessive wear. The best method is tactile (time consuming) it consists of running the rope through the fingers a little at a time, flexing it into a bight and feeling for soft spots or areas of reduced diameter as well as looking for the more obvious mechanical damage.
The line should be allowed to dry naturally in a well-aired place, and then re-bagged but only when absolutely dry. Pack a damp line at your peril.
New ropes
There is a good reason why new rope's are best soaked before use. It shrinks the rope (up to 5% on cheap semi static) and this serves to compact the sheath and tighten it onto the core, improving it's wearing properties. This procedure also helps prevent sheath slippage during the first few time used, until sheath and core are properly bedded together.
Soak the rope in clean water, drain and squeeze out surplus water by pulling the rope through an anchored descender. Repeat process two or three times, each time pulling the rope through the descender in the same direction. Hang the rope up to dry for a few days. If the sheath has crept along the line, hot cut new ends to prevent any unravelling, ensuring you do not cut off the line’s CE identification, if unavoidable you will need to replace this label.
Marking lines
Lines
must be marked with a CE number, but other useful information may be to indicate
length, year put into service and serial number for record keeping. We mark our
lines with bar codes; you can have so much information in a very small space. It
is important that this information remains with the rope throughout its life.
There are many different methods of marking, the main criteria being durability
and that the information is always legible.
My preferred method is to mark the line both ends on coloured heat shrink tube (the colour denoting year in service. The information is written on this with waterproof ink, and protected by a transparent heat shrink tube, sealed with a hot melt adhesive tape. This type of marking is extremely durable and is removed only by cutting the line.
PVC tape can be used on its own (I have read much of the action of the solvent in the adhesive damaging the line, but providing the tape is applied to the very end of the line, it will do no harm). Finally, held firmly in place by transparent heat shrink tube. This method works but, in practise a film of dirty water seems to creep beneath the heat-shrink sleeve and eventually obscure the figures unless sealed with hot melt tape.
Rope, showing
the braided and twisted three strand construction together with the data tape
that runs the entire length.
Polyprop rope,
instantly recognisable as a blue three strand twisted rope. Found on Farms,
construction sites and Is technology on top of rope construction or can we expect something radical? I think we now have the best that is available at this present time, manufactures of rope just don’t make for the rescue market, industrial users will always be the biggest consumers. But add together sports climbing with the need for specific lines together with top class sailing and we can see advances in rope design and construction that are filtering back into rescue rope manufacture.
Rope or Line? It’s like Carabiner or Karabiner? everyone has an opinion, so this is mine. I recall back in my early days as a young firefighter, being told by an individual who had worked with rope for all his life, that rope is the generic name of the manufactured
Choice of rope
The optimum rope for normal use is 11mm diameter nylon rope designed for rescue use. Strong enough to provide a good safety margin 3000Kg WLL, and be also sufficiently robust enough to withstand several years of use, providing you look after it. Weight is not such a concern, as it with sports climbing, there will always be helping hands to transport kit. This same rope must be suitable for all purposes (Controlled descent, safety line, establishing anchors and belays)
When
I first became involved in line rescue work, two types of line commonly were
used. An 11mm Static line for all descending/ascending and stretcher work (twin
line working was not common in those days) and finally a 9mm Dynamic line for
establishing belays. The latest lines using modern manufacturing techniques now
offer us lines that are sometimes termed low-stretch or industrial. These lines
are now the automatic choice for rescue professionals; the limited stretch makes
them ideal for all our applications. The Military/Law Enforcement and sports
cavers will still prefer the static lines, and for Sports climbers the 9mm
dynamic, for its ability to take a fall and its lightness.For rescue work we now have the line that most suits our needs, the 11mm Semi static in working lengths up to 200m, 400m + are available, but these are monsters to handle and heavy to transport.
Special applications call for special ropes, most of my lines are 100m lengths, that for me is the all-round working rope length, not too heavy or bulky for a rope bag. However It is vitally important for any rescue team to assess the need for longer ropes, normally 200m is the longest commercially available. Longer lengths can be supplied but are special order and delivery times normally reflect this. Ropes of one continuous length can make life such a lot easier. The task of passing a knot or adding additional line during a descent can be time consuming and tiring for the rescuer.
Rope must be seen as a consumable, a new rope can be ruined first time it is used. You must be prepared for that, both emotionally and financially, believe me. A lot has been written regarding the working life of a line, in my experience lines in daily use will be worn out and require retiring long before they reach their age limit. For the record, 5 years of regular use seems to be the figure manufacturers have adopted. For rescue teams, up to 8 years is good for me. After all, the line is not being used every day and providing the line has never been shock loaded and is well maintained (as it should be, your life depends on it) it will be OK.
In my experience teams never buy long enough lengths and this failure generally proves expensive in the long term. As a supplier of equipment, including lines, it is more profitable for me to sell you two 50m lines than one 100m line. The longer has to be the most economic choice, its always the ends, sometimes the first 15-20m that will be worn the most. Even by rotating the line regularly, eventually they will have to be cut off, generally leaving a piece only 30m long, which is has very little practical use. However the 100m line can withstand having several ends cut off and still leave you with a good working line. I see this daily on the Rollgliss systems we overhaul, a too a short line was purchased initially and as only the running end that has been ruined, the entire line has to be replaced to maintain a good working length.
Transporting ropes
Ropes should always be stored and carried in rope bags. A well-designed bag, besides being far easier to stow and handle than hanked or coiled line, will protect the line from all kinds of damage. Coiled lines will tangle or develop kinks caused by twisting the rope, I like my lines to be packed tight in a hap-hazard fashion in the bag, reducing chaffing whilst in transit, my second choice is to 'chain a rope'. Finally the environment that we work in can be harsh, it makes much better sense to wear out the bag than damage a line. A line, which is dirty, is not only destroying itself but also your hardware. Even fine grit and dust, especially the oxides from aluminium equipment can rapidly wear out metal equipment and lines alike, and once embedded it is very difficult to subsequently remove all these particles from the rope.Lines like to be kept cool, dry and in the dark. I always keep my lines in their bags, damage from Sunlight or rather, ultra violet light will degrade the line, but this takes ages, the line will be worn out long before this type of damage becomes a concern. Most important is to ensure that lines are stored clean and dry.
After each operational use, lines must be inspected for damage and washed if necessary. Apart from normal surface abrasion which is more or less obvious, the worst thing that can happen to a line is contamination by chemicals, once identified and confirmed, the line or the contaminated end must be disposed off, you just cannot take that risk. Materials used in line construction are particularly stable polymers and are affected by very few common chemicals, however, it is well known that nylon is severely affected by even quite dilute acids, and that polyesters are attacked aggressively by strong alkali's.
Washing and inspection
Using a rope, which has become impregnated with grit, is also a recipe for disaster. Each time the rope is loaded over a pulley or squeezed through a descender a multitude of microscopic particles of grit and metal oxides are forcibly ground into the fragile yarn filaments of the kern and some weakening is inevitable. Thorough washing is important to remove as much as possible of this contamination that abrades the internal fibres of the line. A line cannot be properly inspected for any surface damage that may have occurred until it has been cleaned. Superficial dirt can be removed by simply sloshing the rope around in running water, avoid hosepipes or a Pressure washer, as these may force dirt into the core of the line.
For effective
cleaning, lines can be washed in a washing machine, normal wash temperature 40C.
Chaining the lines can prevent tangling. Other items, webbing or harness can be
stuffed it into a mesh wash bag. Adding normal amounts of a fabric softener is
useful and acceptable as it replaces the yarns normal Teflon / anti-static
lubricants that are used in the manufacturing process.Regular machine washing is not harmful to the line, remember that the same fibre used in lines is that found in ordinary clothing, which is designed to be washed every few days. I always us a detergent, it helps the cleaning process, but look for PH neutral types, I have used soap flakes in the past but have been disappointed with the results. I also ensure the lines go through a full rinse cycle, which I feel is important.
Pictured is a
double jacket rope ( Orange over Black) laid over a four strand braided kern.
The double jackets give excellent wear characteristics but the two mantles
were prone to slippage. This is easily resolved by soaking the rope to induce
shrinkage and pulling the wet rope through a descender a few times whilst under
tension. Unfortunately many manufacturers have dropped this excellent
design. After washing, lines should be carefully inspected for damage or signs of excessive wear. The best method is tactile (time consuming) it consists of running the rope through the fingers a little at a time, flexing it into a bight and feeling for soft spots or areas of reduced diameter as well as looking for the more obvious mechanical damage.
The line should be allowed to dry naturally in a well-aired place, and then re-bagged but only when absolutely dry. Pack a damp line at your peril.
New ropes
There is a good reason why new rope's are best soaked before use. It shrinks the rope (up to 5% on cheap semi static) and this serves to compact the sheath and tighten it onto the core, improving it's wearing properties. This procedure also helps prevent sheath slippage during the first few time used, until sheath and core are properly bedded together.
Soak the rope in clean water, drain and squeeze out surplus water by pulling the rope through an anchored descender. Repeat process two or three times, each time pulling the rope through the descender in the same direction. Hang the rope up to dry for a few days. If the sheath has crept along the line, hot cut new ends to prevent any unravelling, ensuring you do not cut off the line’s CE identification, if unavoidable you will need to replace this label.
Marking lines
Lines
must be marked with a CE number, but other useful information may be to indicate
length, year put into service and serial number for record keeping. We mark our
lines with bar codes; you can have so much information in a very small space. It
is important that this information remains with the rope throughout its life.
There are many different methods of marking, the main criteria being durability
and that the information is always legible. My preferred method is to mark the line both ends on coloured heat shrink tube (the colour denoting year in service. The information is written on this with waterproof ink, and protected by a transparent heat shrink tube, sealed with a hot melt adhesive tape. This type of marking is extremely durable and is removed only by cutting the line.
PVC tape can be used on its own (I have read much of the action of the solvent in the adhesive damaging the line, but providing the tape is applied to the very end of the line, it will do no harm). Finally, held firmly in place by transparent heat shrink tube. This method works but, in practise a film of dirty water seems to creep beneath the heat-shrink sleeve and eventually obscure the figures unless sealed with hot melt tape.
Rope, showing
the braided and twisted three strand construction together with the data tape
that runs the entire length.
Figure of 9?
What makes a good knot? it must be easy to tie, easy to untie and not
damage the line, finally it must reduce the breaking strain of the rope by an
absolute minimum. Remember, when a rope breaks it invariably breaks at the knot!
Widely recognised as one of the strongest knots, the figure of 8 is first choice
amongst rescue professionals. Unfortunately only 1 out of 10 who claim to be
able to tie the knot can do so correctly. Have you ever tied this most basic
knot, had it fully loaded and noticed that one or more turns in the knot have
been left loose?
The most common of all the knots used in rope rescue.
Tied on a single rope it makes an excellent stop knot, more commonly tied on the
bight, it forms a secure attachment point. When tied "re-rove" it secures the
rope directly to an anchorage point.
The sequence to tieing a good knot is easy, just follow the following order:
The figure of 9
knot, it's just the figure of 8 with an extra turn (8+1=9) hence the origin of
its name. The knot is perhaps 1% or 2% stronger than the figure 8. Such a small
margin it's not worth worrying about.
Figure of 9 (top view)
We do have
figure 9 knots on our rapid deployment kits. The knot is pre-tied and tensioned.
It takes a little longer to dress this knot and ensure that none of the lays are
twisted.
Figure of 9 Bottom view
The most common of all the knots used in rope rescue.
Tied on a single rope it makes an excellent stop knot, more commonly tied on the
bight, it forms a secure attachment point. When tied "re-rove" it secures the
rope directly to an anchorage point. The sequence to tieing a good knot is easy, just follow the following order:
- Choose the right knot for task
- Tie the knot correctly leaving sufficient tail for a stopper if required
- Dress the knot, ensuring the lay of the rope is not twisted or crossing over each other
- Tension the knot, easing all parts snugly together
- Check the knot visually
The figure of 9
knot, it's just the figure of 8 with an extra turn (8+1=9) hence the origin of
its name. The knot is perhaps 1% or 2% stronger than the figure 8. Such a small
margin it's not worth worrying about. Figure of 9 (top view)
We do have
figure 9 knots on our rapid deployment kits. The knot is pre-tied and tensioned.
It takes a little longer to dress this knot and ensure that none of the lays are
twisted. Figure of 9 Bottom view
Suspension Trauma update
Advice for first aiders responding to harness suspension
incidents
Following completion of an evidence based review of published medical literature, HSE has clarified guidance on the first aid management of a person falling into suspension in a harness who may develop 'suspension trauma'.
The key recommendations are:
No change should be made to the standard first aid guidance for the post recovery of a semi-conscious or unconscious person in a horizontal position, even if the subject of prior harness suspension.
No change should be made to the standard UK first aid guidance of ABC management, even if the subject of prior harness suspension. A casualty who is experiencing pre-syncopal symptoms or who is unconscious whilst suspended in a harness should be rescued as soon as is safely possible.
If the rescuer is unable to immediately release a conscious casualty from a suspended position, elevation of the legs by the casualty or rescuer where safely possible may prolong tolerance of suspension.
First responders to persons in harness suspension should be able to recognise the symptoms of pre-syncope. These include light headedness; nausea; sensations of flushing; tingling or numbness of the arms or legs; anxiety; visual disturbance; or a feeling they are about to faint. (Motionless head up suspension can lead to pre-syncope in most normal subjects within 1 hour and in a fifth within 10 minutes.)
Following completion of an evidence based review of published medical literature, HSE has clarified guidance on the first aid management of a person falling into suspension in a harness who may develop 'suspension trauma'.
The key recommendations are:
No change should be made to the standard first aid guidance for the post recovery of a semi-conscious or unconscious person in a horizontal position, even if the subject of prior harness suspension.
No change should be made to the standard UK first aid guidance of ABC management, even if the subject of prior harness suspension. A casualty who is experiencing pre-syncopal symptoms or who is unconscious whilst suspended in a harness should be rescued as soon as is safely possible.
If the rescuer is unable to immediately release a conscious casualty from a suspended position, elevation of the legs by the casualty or rescuer where safely possible may prolong tolerance of suspension.
First responders to persons in harness suspension should be able to recognise the symptoms of pre-syncope. These include light headedness; nausea; sensations of flushing; tingling or numbness of the arms or legs; anxiety; visual disturbance; or a feeling they are about to faint. (Motionless head up suspension can lead to pre-syncope in most normal subjects within 1 hour and in a fifth within 10 minutes.)
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