Abstract: A safety device comprising a support harness that includes at least one safety cable, and preferably a pair of safety cables. The end of the safety cable has a snap hook designed to releasably connect to the structure. In application, the safety harness is worn by the worker and as the worker ascends or descends the structure, the worker continuously releases and then connects one of the snap hooks to the structure such that at least one safety cable is connected to the structure at all times. The safety harness includes sensors for detecting whether the worker is ascending or descending the structure, for detecting whether at least one of the snap hooks are connected to the structure, and detecting when the worker is attempting to open the snap hook.

Abstract: A fall arrest system includes a ladder configured to provide access to an elevated structure and a fall arrest device configured to be secured to the elevated structure, the fall arrest device including an upper anchor, the upper anchor including a first end configured to be secured to the elevated structure and a second end distal from the first end.

Abstract: Disclosed herein is a novel configurable strap apparatus that may comprise end clasps attachable to zipper sliders disposed on a zipper edge of the strap. An end clasp may attach to a zipper slider creating a strap loop that facilitates wearing the strap around the neck, or over the shoulder. An accessory, such as a carrying pouch, may be attached to and thereby suspended from an end clasp. Alternatively, an end clasp may attach to a zipper slider creating a strap loop that facilitates capturing and thereby suspending an accessory such as a beverage bottle.

Abstract: A fall arrest system includes a ladder configured to provide access to an elevated structure and a fall arrest device configured to be secured to the elevated structure, the fall arrest device including an upper anchor, the upper anchor including a first end configured to be secured to the elevated structure and a second end distal from the first end.

Abstract: A harness assembly to assist in and secure a fireman's carry of a victim. The harness assembly includes an adjustable strap to be secured around the victim and an adjustable strap to be secured over the shoulder and under the armpit of a carrier. A harness system includes two harness assemblies with one harness assembly being attached around a leg of the victim and one shoulder of the carrier and the other harness assembly being attached around the chest of the victim and the other shoulder of the carrier. The straps are adjustable so that they can be cinched.

Abstract: A fall arrest ladder system including a housing assembly having a retractable lanyard, braking system, safety line, and webbing belt is disclosed. The fall arrest system allows for the safe deceleration of the user from an elevated position on a ladder to prevent the user from making harmful contact with the ground. The safety line and retractable lanyard are each attached to a ladder and then attached to the webbing belt worn by the user, permitting the user to freely move along the length of the ladder while remaining tethered securely in the event of a slip or fall from the ladder. The safety line prevents the user from falling away from the ladder while the retractable lanyard and incorporated braking system decelerate the user during a downward fall.

Abstract: A weight lifting system includes a harness having a body with a thickness, the body having a contoured shape to fit around a shoulder of a user; an opening extending through the thickness of the body and sufficiently sized to receive a head of the user therethrough; and a cradle extending from a back surface of the harness and contoured to receive a weight bar within a channel.

Abstract: A safety securing device has two carabiners intended to receive a securing element. Each of the carabiners includes a hook provided with an opening. A detection device is activated upon insertion of the securing element into the hook. A closure door and a device for locking the door are coupled to a stressing device arranged to activate the locking device when the door is closed. The carabiners are interconnected by a transmission device that connects the detection device of one carabiner to the locking device of the other carabiner. The activation of the detection device of one of the carabiners triggers the deactivation of the locking device of the other carabiner.

Abstract: A fall arrester is provided and includes a pawl and connecting element that are configured such that the pawl and connecting element rotate in a common direction to move the pawl to an engaging position in response to a first predetermined force applied to the connecting element in a first direction, and to allow the pawl to rotate away from the connecting element as the pawl moves to the engaging position in response to a second predetermined force applied to the connecting element in a second direction that is different than the first direction.

Abstract: A length of strap having a handle along one end and a hookup loop extending from the handle to attach to a load. A release knot disposed about the free end of the strap having a bridge to the handle. The handle is disposed to bear the weight of a load alternatively on the strap or the handle when a worker lifts the handle. The knot holds fast when it is bearing the weight, and is slidably disposed when the weight is born by the handle.

Abstract: There is provided a climbing locking system for climbing ladders in particular of a wind power installation. The climbing locking system has at least one climbing ladder segment having a longitudinal direction and at least one open end for accommodating a fall arrester which can move back and forth as a climbing protection system along the longitudinal direction. The climbing locking system also has at least one climbing locking unit at the at least one open end of the climbing ladder segment. The climbing locking unit is fastened pivotably to the climbing ladder segment and has a locking position for locking a movement of a fall arrester along a direction of the climbing ladder segment and a passing position for allowing a movement of the fall arrester along the longitudinal direction of the climbing ladder segment in both directions.

Abstract: A tensioning assembly having a drive pulley, a tension pulley and a tension adjustment system is provided. The drive pulley has a first drive pulley channel and a second drive pulley channel. The tension pulley has a first tension pulley channel and a second tension pulley channel. The second tension pulley channel is aligned with the first drive pulley channel. The first drive pulley channel and the second drive pulley channel of the drive pulley and the first tension pulley channel and a second tension pulley channel of the tension pulley are configured and arranged to engage and route an endless looped member. The tension adjustment system is coupled to adjust the distance between the drive pulley and the tension pulley to adjust the tension in the endless looped member in relation to the drive pulley.

Abstract: In a ladder assistance device, a cable pulled by a controlled driving apparatus is laid in a loop along the height of the ladder, the user being attached to the cable by a lanyard, a sensor element detecting movements along the ladder, a control element controlling the driving apparatus. A remote control activates or deactivates assistance and allows user weight input, the remote control remaining in the reach of the user and including a stop button deactivating assistance and two activation buttons for activation of assistance, one each for “up”/“down”. A memory stores sets of control values for assistance level(s) for each direction of movement, corresponding to at most two levels in the steady state of the assistance. The program of the control element allowing: the selection that corresponds to the user weight, the activation which is only obtained by the activation buttons of the remote control.

Abstract: A fall restraint system having a retractor assembly including a housing assembly that is mounted onto an aerial apparatus. A base pulley assembly is also mounted onto the aerial apparatus. A cable having first and second ends is partially stored within the housing assembly, whereby the first end is fixed within the housing assembly. The second end is threaded around the base pulley assembly and is also fixed onto the aerial apparatus. Tensioning means keep a predetermined tension on the cable while the aerial apparatus extends from a retracted position to an extended position and vice-versa.

Abstract: A hook elevator system, kit and method for assisting an individual in ascending a series of horizontally ascending tree limbs. One or more limb engaging hooks are provided along with a pole for elevating a given hook above the user's head in order to access a given limb. A rope extends from the hook to a harness worn by the user for enabling the user to winch up to the hook, such as from a ground location, with the hook being removed and elevated to a further ascending limb by the wearer once he/she has reached the support of the initial limb. Alternatively, additional hooks can provide additional flexibility in allowing the user to move from limb to limb, and which facilitates the user's ability to access an elevated and supported location of the tree for setting up a tree stand/platform.

Abstract: An upright tree stand includes a base pole section with a support pad, an intermediate pole section or sections, a lowermost one of which is connected to the base pole section by a knuckle hinge, and a top pole section. The top pole section is provided with a top securement assembly which utilizes a self-tapping screw and a remotely operable, dual-action ratchet wrench. The base pole section is initially secured to a tree. The intermediate pole section or sections and the top pole section are then swung, about the knuckle hinge, into an upright position. This movement is accomplished with sufficient force to embed the tip of the self-tapping screw into the tree. Operation of the dual-action ratchet wrench, remotely from the ground, will accomplish the positive securement of the top of the upright tree stand to the tree while the user remains safely on the ground.

Abstract: The present invention relates to a securing device for protecting individuals against falling, with two stop elements which can be attached releasably to a positionally fixed securing element and can be connected via a connecting element to the individual. Each stop element has a locking device which can be adjusted between an unlocking state, in which the stop element can be attached to the securing element or released therefrom, and a locking state, in which the stop element cannot be released from the respective securing element. A coupling device is coupled to the locking devices of the stop elements in such a manner that, in the unlocking state, the locking device of the other stop element is blocked in its locking state. A preferred construction of the coupling device has a blocking lever which can be pivoted into a blocking position for blocking the locking device in its locking state.

Abstract: A system configured for lifting or lowering a tool carriage device via a ladder climbing structure is described. The tool carriage device may be adapted to enclose and transport a payload and include a fall arrest grab with an overspeed brake to stop an uncontrolled descent of the carriage device. The tool carriage device may include obstruction sensors to detect an obstruction along the path of the carriage device.

Abstract: The fall arrester (10) is part of a climbing protection system for preventing a user of a ladder, a platform or the like from falling. The fall arrester (10) is movable along a guide rail (12) and has a rotatably mounted pawl (18) which, in the event of a fall, runs against catching stops (16) in the guide rail (12). A connecting element (40) is attached to the pawl (18) and the user can be secured to the connecting element (40) by a lanyard. The connecting element (40) is hinged to the pawl (18). The connecting element (40) can be hinged to the pawl (18) such that the connecting element (40) is coupled releasably rotation-resistant to the pawl (18) and the coupling (50, 52) is released in the event of a predetermined force on the connecting element (40). The connecting element can be formed as a damping element (40) which deforms in the event of a predetermined force.

Abstract: An adjustable hang ladder includes a main ladder section and a hang ladder section secured to the main ladder section. The hang ladder section has a hang ladder insert pivotally secured to an attachment section and locked in place by a locking mechanism. The hang ladder section is provided with a fall arresting and damping arrangement designed for connection to a roofer using the ladder for providing a cushioning effect in the event the roofer falls from the ladder.

Abstract: The invention relates to a system for protecting individuals during work on ladders with steps. The system comprises an anti-fall protection device and a ladder climbing assistance device. The anti-fall protection device and ladder climbing assistance device are attachable to an individual by means of lines, safety harness or the like. The anti-fall protection device comprises a hinge for being secured on a guide means and anti-fall protection device and guide means are adapted to each other so that the anti-fall protection device is able to slide on the guide means when the hinge is influenced by a force in one direction and is securely locked on the guide means when the hinge is influenced by a force in another direction.

Abstract: The invention comprises a kit having tools attachable to a ladder to stabilize the same. The tools include a stabilizer tool attachable to the ladder and capable of circumscribing a vertical object to thereby stabilize the ladder. Additionally, there are provided extensions attachable to the stabilizer tool having clamps, movable to engagement of a building or the like by its gutters or other protuberances.

Abstract: A safety accessory for use with a ladder to slow the speed of an accidental fall of a worker, who works in an elevated position. The accessory has a C-shaped track member and a slide body that moves inside the track member. The worker's harness is secured to the slide body. Contact surfaces of the track member and the slide member are serrated to slow the speed of an accidental fall. A plurality of locking wedge members is positioned in the channel formed by the track member to further decrease the speed of an accidental fall.

Abstract: A safety-featured ladder, including taut rope wrapped over top of the top rung and under bottom of the bottom rung and fixedly connected to the ladder when downward force is applied to the rope in front of the ladder. In a first embodiment, a sleeve including a pulley subsystem is attached to a body harness worn by a climber and can move or slide along the rope only when climbing up ladder. In a second embodiment, a sleeve including a different pulley subsystem including a centrifugal brake is attached to a body harness worn by a climber and can move or slide along the rope when climbing up or climbing down. However, if the climber loses footing and starts to fall the sleeve grabs the rope, and/or the rope grabs the sleeve, which prevents the climber from falling more than a few inches and from injury. Hooks at top of the ladder can hook around transverse cables atop poles.

Abstract: The present disclosure relates to a stop element for a securing device, with a contact element. A locking device is shiftable between unlocked and locked states. The stop element is attachable to and releasable from the securing element in the unlocked state and not releasable from the securing element in the locked state. The locking device has an actuating device which is shiftable between an active position and a passive position and when in its active position blocks the locking device in its unlocked state and is transferable into its passive position, in which the locking device is shiftable into its locked state, when the stop element is attached to the securing element. The contact element may form part of the actuating device such that the actuating device can be shifted into its passive position when the securing element contacts the contact element.

Abstract: A safety ladder that protects a climber from a fall is disclosed. The device provides a ladder having a plurality of rails and rungs, one of the rails being an elongated channel having multiple flanges surrounding a passageway, a pair of the flanges defining there between a gap. A locking member is configured to travel upwardly in the passageway, the locking member having a beam, a cam section at one end portion of the beam and an eyelet that is positioned outside of the passageway. A cable connects a climber to the connector section. The cam section is specially configured and forms an anchor with the channel in a locking position when a climber pulls down on the cable and locking member. The rail or rails flanges form an acute angle with the rungs.

Abstract: A fall arrest system formed from a suspension seat supported by a plurality of shoulder straps coupled to an adjustable waist belt is disclosed. The suspension seat formed from a platform that is suspended beneath the adjustable waist belt such that the suspension seat is positioned generally vertically with straps. The shoulder straps include breakable connections. During a fall, the breakable connections break and the suspension seat falls into a horizontal position to support a person about which the fall arrest system is attached. During the fall, a self-extraction ladder may also be deployed. The fall arrest system may also include fabric layers attached to front and rear sides of shoulder straps. In addition, the side areas under a user's arms between the front and rear sides are open.

Abstract: A climb assist system is disclosed that dynamically adjust the rate and level of assist of a climber as the climber needs may change over the period of traverse of the ladder. A sensor detects the state of a person, such as the load exerted by the climber on a ladder exerts on an assist rope, to provide an upward support force on the climber to compensate the climber's weight. Additionally, a sender is provided to transmit the load data to a receiver and a receiver to receive the data from the sender. A controller interprets the received data and thereafter provides control through a controlled motor and drive to provide energy to the assist rope.

Abstract: An adjustable hang ladder includes a main ladder section and a hang ladder section secured to the main ladder section. The hang ladder section has a hang ladder insert pivotally secured to an attachment section and locked in place by a locking mechanism. The hang ladder section is provided with a fall arresting and damping arrangement designed for connection to a roofer using the ladder for providing a cushioning effect in the event the roofer falls from the ladder.

Abstract: A climb assist system is disclosed that dynamically adjust the rate and level of assist of a climber as the climber needs may change over the period of traverse of the ladder. A sensor detects the state of a person, such as the load exerted by the climber on a ladder exerts on an assist rope, to provided an upward support force on the climber to compensate the climber's weight. Additionally, a sender is provided to transmit the load data to a receiver and a receiver to receive the data from the sender. A controller interprets the received data and thereafter provides control through a controlled motor and drive to provide energy to the assist rope.

Abstract: This fall-prevention device comprises a body on which, mounted so as to rotate about a shaft, there is a wheel designed to press and roll on a belay support, and means for locking the body of the fall-prevention device on the belay support, the wheel comprising at least one centrifugal engagement device that can be moved between a disengaged position and an engaged position. The locking means comprise at least one locking member mounted so as to rotate on the body about the rotation shaft of the wheel, the locking member comprising a chock arranged to be inserted between the belay support and the wheel when the engagement device is in its engaged position, so as to immobilize the fall-prevention device on the belay support.

Abstract: In a ladder assistance device, a cable pulled by a controlled driving apparatus is laid in a loop along the height of the ladder, the user being attached to the cable by a lanyard, a sensor element detecting movements along the ladder, a control element controlling the driving apparatus. A remote control activates or deactivates assistance and allows user weight input, the remote control remaining in the reach of the user and including a stop button deactivating assistance and two activation buttons for activation of assistance, one each for “up”/“down”. A memory stores sets of control values for assistance level(s) for each direction of movement, corresponding to at most two levels in the steady state of the assistance. The program of the control element allowing: the selection that corresponds to the user weight, the activation which is only obtained by the activation buttons of the remote control.

Abstract: A method for regulating the traction in a line (13) of a ladder climbing assistance device, in which method any movement of the line (13) is sensed and in dependence of the sensed movement either increasing the traction in the line to a predetermined high level (L1), maintaining the traction at a predetermined high level (L1), or decreasing the traction to a predetermined low level (L0). Furthermore, a ladder climbing assistance device comprising a line (13) that is movable along the ladder (1) and a motor (8) with a power outlet arranged to provide an essentially constant traction in the line (13). The ladder climbing assistance device comprises sensing means (25) for sensing any movement of the line (13), which sensing means is connected to controlling means (26) for controlling the power outlet from the motor (8) in response to signals from the sensing means in the above-described manner.

Abstract: A height safety system is disclosed for use with an elevated work area including: an elongate member; first and second attachment means; the first attachment means is adapted to restrain the member in use at a lower region of the mast; the second attachment means is adapted to restrain the member in use at about the height of the elevated work area; and a fall restraint device which is adapted to be attached to the member in use at an upper region of the mast.

Abstract: A safety-featured ladder, including taut rope wrapped over top of the top rung and under bottom of the bottom rung and fixedly connected to the ladder when downward force is applied to the rope in front of the ladder. In a first embodiment, a sleeve including a pulley subsystem is attached to a body harness worn by a climber and can move or slide along the rope only when climbing up ladder. In a second embodiment, a sleeve including a different pulley subsystem including a centrifugal brake is attached to a body harness worn by a climber and can move or slide along the rope when climbing up or climbing down. However, if the climber loses footing and starts to fall the sleeve grabs the rope, and/or the rope grabs the sleeve, which prevents the climber from falling more than a few inches and from injury. Hooks at top of the ladder can hook around transverse cables atop poles.

Abstract: A mobile mount for attachment of a fall arrest system is provided for example for aircraft and includes a base carried on ground wheels and a support which is adjustable in height upstanding from the base and an arm cantilevered over the base. At least one receptacle is mounted on the arm of the support at a position located over the base for attachment to a personal fall arrest system including a harness for one or more persons, with the receptacle, base and support being designed and arranged to receive a loading from the personal fall arrest system sufficient to accommodate a fall of the person from the elevated structure.

Abstract: A fall arrest assembly that includes a rotational drum, at least one pawl and a catch is provided. The rotational drum is configured to rotate in response to a movement of a lifeline. The least one pawl is in rotational communication with the rotational drum. The at least one pawl is further configured to pivot about a pivot connection in response to select rotational velocities of the rotational drum. The at least one pawl is also configured to engage the catch when the at least one pawl pivots in response to the select rotational velocities of the rotational drum to stop the rotation of the rotational drum and movement of the lifeline. An elastic bushing for each pivot connection is also used. Each elastic bushing is positioned about an associated pivot connection of an associated pawl. The elastic bushings deform in shape as an associated pawl engages the at least one portion of the catch.

Abstract: A motorized climb assist assembly is provided. The motorized climb assist assembly includes a looped belt, an attaching member, a motor assembly and a fall arrest system. The attaching member is coupled to the looped belt. A safety harness is in turn coupled to attaching member. The motor assembly includes a motor and a drive sheave. The motor has a drive shaft. The drive sheave is coupled to the drive shaft. In addition, the drive sheave is in contact with the looped belt. The fall arrest system is integrated with the drive sheave and is configured to limit the looped belt movement as the result of a fall event.

Abstract: A catch device, as part of a fall protection for ladders and similar climbing devices, for application in a guide rail with a C-profile, includes a body and at least two pairs of rollers, arranged in the body so as to run inside the guide rail. At least one pair of rollers is rigidly fixed to the body and one roller pair is arranged to pivot about an axis at right angles to the longitudinal axis of the guide rail and which runs up to the rotational axis of the roller pair. The pivoting roller pair can be fixed in a secure position such that the pivoting roller pair is fixed on a shaft, mounted so as to rotate in the body, the upper end of the shaft projecting from the body and having an indent. A hanging latch is connected to the body which may engage in the indent. The hanging latch can be locked in the engaged position.

Abstract: A safety accessory for use with a ladder to slow the speed of an accidental fall of a worker, who works in an elevated position. The accessory has a C-shaped track member and a slide body that moves inside the track member. The worker's harness is secured to the slide body. Contact surfaces of the track member and the slide member are serrated to slow the speed of an accidental fall. A plurality of locking wedge members is positioned in the channel formed by the track member to further decrease the speed of an accidental fall.

Abstract: A climbing assistance device having a connection assembly disposed at a predetermined location on the structure, a yoke attachable to a person, a counterweight connected to the yoke by a cable which passes through a pulley system, and a stabilizer operative to stabilize the counterweight to prevent rotation thereof. By employing the stabilizer, the counterweight remains stable during ascent and descent, and the load of the counterweight is controlled.

Abstract: A climb assist system for use in combination with a climbing structure having upper and lower ends. The climb assist system includes a header assembly for attachment to the upper end of the climbing structure. The header assembly includes a pulley frame having opposing front and rear ends and front and rear pulleys located adjacent the front and rear ends. Elongated guide members extend from the header assembly downwardly toward the lower end of the climbing structure. A climb assist cable extends over the front and rear pulleys and includes a front cable portion extending along a front side of the climbing structure for attachment to a worker, and a rear cable portion extending along a rear portion of the climbing structure adjacent to the guide members and attached to a counterweight for offsetting the worker's weight. The counterweight includes guide portions engaged with the guide members to guide the counterweight in a path closely adjacent to the ladder.

Abstract: A climb assist system is disclosed that dynamically adjust the rate and level of assist of a climber as the climber needs may change over the period of traverse of the ladder. A sensor detects the state of a person, such as the load exerted by the climber on a ladder exerts on an assist rope, to provided an upward support force on the climber to compensate the climber's weight. Additionally, a sender is provided to transmit the load data to a receiver and a receiver to receive the data from the sender. A controller interprets the received data and thereafter provides control through a controlled motor and drive to provide energy to the assist rope.

Abstract: The invention is a device capable of providing fall protection for a climber, which enables the climber to remain suspended after a fall, or to descend in a controlled manner. The device utilizes a safety line, which is governed by a novel combination of: a mechanism which applies a continuous level of resistance to the safety line, and a variable force which pulls on the safety line in the opposite direction of a climber's descent during a fall. Together, these two forces serve to hinder the free travel of the safety line in the direction of a fall. The variable opposing force, when fully applied to the safety line, combines with the continuously applied resistance to arrest the climber's fall. However, when this opposing force is applied to a lesser degree, the combination of resistance applied against the safety line is not sufficient to suspend the climber, and the climber can descend.

Abstract: A method is provided for assisting multiple climbers in ascending and descending the same ladder using an apparatus that includes a plurality of counterweights and a rigging system coupled to the counterweights, the rigging system includes at least two subsystems, each subsystem includes at least one cable, at least one pulley, and at least one harness. The method includes configuring a first subsystem to assist a first climber in ascending and descending the ladder, configuring a second subsystem to assist a second climber in ascending and descending the ladder, coupling a first harness to the first climber, coupling a second harness to the second climber, using the first subsystem to assist the first climber in ascending and descending the ladder, and using the second subsystem to assist the second climber in ascending and descending the ladder.

Abstract: An attachment apparatus for use with a generally vertical radio frequency antenna, the antenna having a housing defining an inside and an outside of the antenna, wherein the housing has an upper portion and a lower portion. The apparatus includes first and second anchor housings connected to the antenna along with a revolving cable having two sections. The attachment apparatus also includes at least one latching mechanism.

Abstract: Disclosed is a climbing safety device in a tower crane including a vertical ladder enabling an operator to move to an overhead operator cab, and a wire rope for ensuring a safety of the operator. The climbing safety device includes a wire rope winding unit for winding or unwinding a wire rope. The wire rope has a ladder structure while being provided, at each side thereof, with engagement balls vertically spaced apart from one another. The climbing safety device also includes a safety unit for guiding a movement of the wire rope while controlling a sudden unwinding of the wire rope. The safety unit includes a sensor for sensing the sudden unwinding of the wire rope.

Abstract: A fall arrest safety device for workers on transmission towers and the like includes a “matched” safety rail and brake trolley. The rail has a profile which includes a non-symmetrical profile portion and the trolley has a passageway of complimentary profile so that the trolley cannot be installed on the rail up-side down. A full body harness worn by a user of the device is clipped to the trolley and the trolley incorporates a brake which is spring-biassed into frictional engagement with the rail. The brake can be disengaged from the rail only by the user deliberately overriding the biassing effect.

Abstract: A fall arrester for a climbing protection system to prevent a person from falling from a ladder, platform, or similar structure. The fall arrester can be guided in a guide rail and has a housing and a pawl with an attachment point where the person to be secured is attached. The pawl is swivellable between an unlocked and a locked position of the fall arrester so that in the unlocked position, the connection line between the rotational axis and the attachment point form an acute angle to the horizontal, and the torque exerted by the spring on the pawl is less than the torque produced by the weight force of the fall arrester when the fall arrester is held at the attachment point.

Abstract: A fall arrest safety device for workers on transmission towers and the like includes a “matched” safety rail and brake trolley. The rail has a profile which includes a non-symmetrical profile portion and the trolley has a passageway of complimentary profile so that the trolley cannot be installed on the rail up-side down. A full body harness worn by a user of the device is clipped to the trolley and the trolley incorporates a brake which is spring-biassed into frictional engagement with the rail. The brake can be disengaged from the rail only by the user deliberately overriding the biassing effect.