OVERHEAD CONSTRUCTION
DROPWIRE ERECTION


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Dropwire had been around since the 1930's was normally erected by an overhead gang.  With the introduction of specialist equipment and the lightweight, plastic covered, Dropwire No. 3, the GPO sought ways for the erection of such to be completed by one person.  In this case they were looking at a case for a one man installer, who would install both the line and telephone instrument.


P.O. ENGINEERING DEPT
ENGINEERING INSTRUCTIONS
LINES
OVERHEAD
E3107
Issue 1, 13.4.66

OVERHEAD DISTRIBUTION
Erection of Cables, Dropwire, Nos. 1, 2 and 3 by One-man Installers

1. General
This Instruction describes the methods to be used by one-man installers when erecting single spans of dropwire re.g. pole to bracket) not involving road or power crossings. Special attention is drawn to the following Instructions:-
Test of wood pole - C 5101.
Description, use and erection of Cables, Dropwire, Nos. 1, 2 and 3 - E 3101
Erection of Cables, Dropwire, Nos. 1, 2 and 3 by two-man installation party - E 3106.
Overhead works - general precautions against accidents - J 1001.
Works in public streets - guarding and lighting of Underground, obstructions and temporary traffic control - J 1150.

2. Limitations in the use of one-man installers
Though suitable jobs can normally be identified quite readily by Routing and Record officers, the final decision on whether the job can be done single-handed must rest with the installer. When surveying the job, the installer must take account of the standard safety regulations as laid down in the Safety Guide RG 41 and where the job cannot be completed safely by one man he should report the fact to his Distribution officer. Typical examples of where the job cannot be done single-handed within the safety regulations are:-

  1. where the ladder footing is insecure and lashing is impracticable.

  2. where the ladder issued to the installer (i.e. No. 4A or No. 5) is not adequate for the work in hand.

  3. where the dropwire must be erected over a road or over power wires.

3. In such circumstances the Distribution officer will, if possible, arrange assistance while the installer is on site; otherwise the job should be completed as soon as possible afterwards by a two-man installation party or by teaming up two one-man installers. The work which can be done single-handed by the installer should be completed on the first visit.

4. Principles underlying the methods to be used
The methods described in detail in pars. 8-12 are based on the following principles:-

  1. The installer should climb and descend poles and ladders with his hands unimpeded

  2. The dropwire should be tensioned from the pole for normal jobs or from the ground when a bracket-to-bracket span is run

  3. Standard safety regulations and precautions as laid down in the Safety Guide RG 41 and in J 1001 must be adhered to.

5. A basic method suitable for most jobs is described in par. 8, and variations of it are given for use when:-

  1. obstructions such as trees prevent the dropwire being readily raised to full height.

  2. bracket-to-bracket spans have to be erected.

The methods described for these special conditions permit the installer to raise the wire to full height while working from the ground.

6. The methods have been designed to reduce the carrying of tools and stores and the climbing of ladders and poles to a minimum, and should be followed as far as practicable. When conditions do not permit them to be adhered to precisely the general principles underlying the methods should be borne in mind.

7. Special items of stores required. The following items are required to carry out the methods described:-

  1. A tool basket line. A 12yd. length of Line, Sash, No. 5, one end to be tied permanently to the handles of the tool basket leaving a free end about 12in. long which should be fitted with a snap hook.

  2. A lashing line. A 10yd. length of Line, Sash, No. 5, for lashing the foot of the ladder when an insecure footing is encountered.

  3. A hand line. A 36yd. length of Line, Sash, No. 2, fitted with a snap hook at one end.

  4. A wiring shackle (see Fig. 1). This is required when it is necessary to raise the dropwire span to full height when working from the ground and where the pole fittings will not allow the hand line or dropwire to pass freely over them. It should be made from an 8in, length of No. 8 gauge steel wire formed into a U shape. A snap hook should be attached to one side of the U and a 12in, length of 1in. light steel chain to the other.

Items (c) and (d) are required only for certain special circumstances (see pars. 10, 11 and 12) and should be kept together in the vehicle ready for use as required.

FIG. 1

8. Erecting dropwire. No obstructions - normal method to be used
In this method the dropwire is first attached to the building and then paid out to the serving pole. Erection at the pole is carried out by the installer pulling up the dropwire by means of the tool basket line after he is secured to the Pole. The sequence of operations is given in Table 1. The Table also indicates the main safety precautions which should be borne in mind.

TABLE 1
ERECTING DROPWIRE - NO OBSTRUCTIONS

  Operations and details of procedure Safety prompts
a. Arrival at premises.
i) Park vehicle near-side to kerb and close to serving pole if possible.

ii) Check access and customer's requirements.

iii) Survey route of span, attachment point, cable run, etc.

iv) Check ladder footing.
 

Do not cause undue obstruction to other road users

 

b. Preparatory work - house end.
i) Display red flag on vehicle where appropriate.

ii) Take tool basket with brackets, clamps, etc. and ladder to the house

iii) Return to vehicle for dropwire (and stores and tools for external earth if required).

iv) Erect ladder.

v) Pay off enough dropwire to reach the bracket point and for lead-in.

vi) Attach the clamp to the dropwire at the estimated position of the bracket.

vii) Tie the dropwire to the handle of the tool basket.

viii) Double the free end of the tool basket line and tuck it in the pocket so that it will be pulled out easily should it become tensioned while the ladder is being climbed.

(ix) Ascend ladder.
 

Erect the ladder with 4:1 slope. Check footing.

Place the dropwire arum so that it does not obstruct traffic.

Climb with hands free at all times.

 

 

c. House fixing, lead-in and external, earth.

i) Pull up the tool basket and secure it to the Ladder.

ii) Fix bracket and attach the dropwire.

iii) Run lead to lead-in point, resisting the ladder to maintain a comfortable working position.

iv) Provide external earth if required.
 

Get a comfortable ladder working position so that the work can be done without  stretching
d. Preparatory work - pole end.

i) Carry ladder and tool basket to serving pole.

ii) Test pole. Inspect footing for the ladder.

iii) Collect the lashing line (if required).

iv) Erect the ladder, lash using lashing line if footing is insecure.

v) Collect, inspect and put on safety belt.
 

If the footing is slippery or insecure the foot of the ladder will require lashing to the pole as explained in RG 41.

Erect the ladder at approximately 4:1 slope

e. Erecting the span.

i) Pay out the dropwire to the pole keeping clear of minor obstructions. Wherever possible lay the dropwire flat on ground.

ii) Cut the dropwire to approximate length and tie it to the handle of tool basket.

iii) Tuck the doubled end of the tool basket line under the safety belt.

iv) Ascend the ladder, lash top of the ladder to the pole, if not done previously, ascend the pole to working position. Secure safety belt.

v) Pull up the tool basket and dropwire, secure the basket to pole fitting.#

vi) Pull up slack in the dropwire, secure temporarily.

vii) Fit clamp.

viii) Tension the dropwire and secure in the clamp.
 

 
f. Terminating and testing.

i) Cut the dropwire to length. Put the excess wire in the tool basket.

ii) Check allocated pair with handset and terminate the dropwire.
 

 
g. Clearing up on work site.

i) Lower the tool basket using the tool line basket.

ii) Descend the pole with the free end of the tool basket line tucked under the safety belt. Unlash ladder at the top in passing.

iii) Take down the ladder, return with the tool basket etc. to the vehicle.

 


9. Obstructions at the house-end of the span
When the obstruction is near the house-end of the span it will usually be possible to clear it while paying out the span. Alternatively it may be possible to place the dropwire through or over the obstruction using Rods, Pruning. The dropwire can then be erected as described in par. 8, Table 1.

10. Obstructions mid-span or near the pole (see Fig. 2)
When the obstruction is mid-span or near the pole it will usually be more practicable for the installer, working from the ground, to raise the dropwire by using the hand line. In this method one end of the hand line is passed over a pole fitting and attached to the dropwire previously laid out to the pole. The other end of the hand line is looped round the dropwire at the point where it is likely to foul the obstruction during erection. The span is then raised by the installer from the ground by pulling on the hand line and using the control loop to guide the dropwire past the obstruction. Full details of the method are given in Table 2.

FIG. 2
 

TABLE 2
ERECTING DROPWIRE - OBSTRUCTION MID-SPAN OR NEAR THE SERVING POLE

  Operations and details of procedure Safety prompts
a. Preparatory work:
i) Proceed as in normal method, Table 1, Sections (a) - (d).
ii) Collect the hand line and wiring shackle.
iii) Pay out the hand line. Clip end to the tool basket handle.
Lash foot of the ladder if footing is slippery or insecure
b. i) Tuck end of the tool basket line under the safety belt. Ascend ladder, lash top to pole if not already done. Ascend pole. Secure safety belt.

ii) Pull up the tool basket, secure it to the fitting.

iii) Fit clamp to the pole fitting.

iv) Fit the wiring shackle to the pole (if required) to ensure free running of the hand line.

v) Pass one end of the hand line over the pole fitting or through the shackle so that the free end reaches the ground.

vi) Descend the pole.
 

Ladder to be lashed using the lashing line on top section if not lashed previously.
c. Erecting the span.

i) Pay out the dropwire as in Table 1, Section (e) (i) passing it round the obstruction.

ii) Cut to approximate length. Secure it to the snap hook of hand line.
 

Place the drum where it will not obstruct traffic.
d. Clearing the obstruction (see Fig. 2).

i) Pass free end of the hand line over the dropwire to form a control loop. Move this control loop along the dropwire to the point where the dropwire is likely to foul the obstruction.

(ii) Working on the ground, hold the control loop in one hand and the line to the pole head in the other. Manipulate the hand line and loop to tension and guide the dropwire into position

(iii) Pull up the dropwire using the hand line; secure the hand line to the base of the pole.

(iv) Remove hand line loop from dropwire span.

(v) Ascend pole and proceed in the manner described in Table 1, Section (e) (vii) and (viii)
 

Check for pedestrians and vehicles in drives before pulling up dropwire.
e. Terminating, testing and clearing up.

Proceed as in the normal method, Table 1, Sections (f) and (g).
 

 

11. Obstructions very near the pole
If the obstruction is very near the pole it may be more satisfactory to place one end of the hand line over or through the obstruction after it has been passed over the pole fitting and then attach it to the end of the dropwire. It can then be used to pull the dropwire into position from the ground.

12. Bracket-to-bracket spans
If it is found necessary to tension dropwire spans from the bracket end, e.g. building to building spans:-

  1. attach the dropwire to the served building.

  2. pay out the span as in the normal method.

  3. erect the dropwire and pass it through the wiring shackle attached to the serving bracket so that the span can be tensioned and secured temporarily by the installer, working on the ground

  4. fit the clamp at the serving bracket to support the span.

13. Combined units
When road crossing or power crossing spans are erected by two one - man installers working together, follow the methods detailed in E 3106 for erecting dropwire by two - man installation parties.


TELECOMMUNICATIONS INSTRUCTION
C Marketing Installation
2 External
A1002
Issue 2, Jan 1974

OVERHEAD DISTRIBUTION
Erection of Cable, Dropwire by One Man Installers

1. GENERAL
This Instruction describes the methods to be used by installers when erecting dropwire.
Special attention is drawn to the following Instructions:-
Test of wood pole - A2 N1351.
Cable Dropwire. Description and conditions of use - A1010.
Cable Dropwire. Construction Practices - A1020.
Overhead works - general precautions against accidents - A2 E5501.
Work in the vicinity of power wires - A2 E5503.
Road Works Guarding Manual.

2. LIMITATIONS IN THE USE OF ONE-MAN INSTALLERS
Though suitable jobs can normally be identified by Routing and Record Officers, the final decision on whether the job can be done single-handed MUST rest entirely with the installer. Other than the qualifications set out in this instruction, which limits the ability of the one-man installer to undertake work applicable to the use of the dispenser (see para 2(a) to (e)), the work of the one-man installer must be limited to three spans, (including the span to the house) and to only one road crossing. When inspecting the job, the installer must take account of the standard safety regulations as laid down in the Safety Guide RG 41 and where the job cannot be completed safely by one man he should report the fact to his Control Officer. Typical examples of where the job cannot be done single-handed within the safety regulations are:-

  1. Where the ladder footing is insecure and lashing is impracticable.

  2. Where the ladder issued to the installer (ie No. 4A or No. 5) is not adequate for the work in hand.

  3. Where the dropwire must be erected over a road and there is insufficient visibility or where traffic is too heavy to allow the method in tables 2, 3A and 3B to be used safely.

  4. Where more than 3 spans (including the span to the house) of Dropwire No. 3 are required.

  5. Where Dropwire No. 4 is required.

3. In such circumstances the Control Officer will arrange assistance while the installer is on site. If this is not possible, work should be undertaken later by an appropriate party. Under no circumstances will the work be withdrawn from a one-man installer and given to another, later. If circumstances are such that a one-man installer cannot complete the work, that part of the work which he can do single handed. including proving the pair to the DP, lead-in and internal work, should be completed prior to leaving the site.

FIG. 1

4. PRINCIPLES UNDERLYING THE METHODS TO BE USED
The methods described in detail in paras 8-16 are based on the following principles:-

  1. The installer should climb and descend poles and ladders with his hands free.

  2. The dropwire should be tensioned from the pole for normal jobs or from the ground when a bracket-to-bracket span is run.

  3. Standard safety regulations and precautions as laid down in the Safety Guide RG 41 and in M4 E0600 must be adhered to.

5. Basic methods suitable for most jobs not involving road or power crossings are described in para 8 and for those involving a road crossing in para 9.

Variations are outlined in the following paragraphs:-
10 - Multispan jobs (3 spans including span to the house) - no obstructions - no road crossings.
11 - Multispan jobs (3 spans including span to the house) - Road Crossing pulling up from house end.
12 - Multispan jobs (3 spans including span to the house) - Road Crossing pulling up from pole end.
13 - Obstructions in line of route.
14 - Crossings over power.
15 - Bracket-to-bracket spans.

6. The methods have been designed to reduce the carrying of tools and stores and the climbing of ladders and poles to a minimum, and should be followed as far as practicable. When conditions do not permit them to be adhered to precisely the general principles underlying the methods should be borne in mind.

FIG. 2
BASE LINE
(12 YARDS SASH No.5 WITH SNAP HOOK )
 

7. SPECIAL ITEMS OF STORES REQUIRED
The following items are required to carry out the methods described:-

  1. A tool basket line. A 12 yard length of Line, Sash No. 2 as a hand line, one end to be tied permanently to the handles of the tool basket, leaving a free end about 12 inches long which should be fitted with a snap hook.
    (Figure 2).

  2. A ladder tie.

  3. A long sashline. A 72 yard length of Line, Sash No. 2.

  4. A medium sashline. A 48 yard length of Line, Sash No. 2.

  5. A short sashline. A 24 yard length of Line, Sash No. 2.

  6. Three Pulleys, Dropwire No. 1 (Figure 3).

  7. A Dispenser, Dropwire No. 1 - loaded with a plywood drum of Cable Dropwire No. 3 (Figure 1). NOTE. Do not use a drum which is nearly empty for erecting dropwire across roads as the wire might slip off the drum and fall into the road. This limitation will not apply to later supplies of dropwire No. 3, identifiable by a red circle on the flange of the drum, which have the dropwire fixed securely to the centre of the drum. Additionally, these drums will have a marker on the inner flange to indicate when the last 100 yards of dropwire has been reached. For safety reasons when fitting Drum of Dropwire to Dropwire Dispenser the inner end of the Dropwire left-exposed for test acceptance purposes should be cut off close to its anchorage.

  8. Safety cones and Signs.

  9. Two Belts, Pole No. 1 (Figure 3a).

FIG. 3
PULLEY DROPWIRE No.1
 

FIG. 3A
BELTS, POLE No. 1

8. ERECTING DROPWIRE - No obstructions and no road crossing
The method shown in Table 1 to be used. In this method the dropwire is first attached to the building and then paid out to the serving pole. Erection at the pole is carried out by the installer pulling up the dropwire by means of the tool basket line after he is secured to the pole. The sequence of operation is given in Table 1. The Table also indicates the main safety precautions which should be borne in mind.

TABLE 1
ERECTING DROPWIRE - NO OBSTRUCTIONS AND NO ROAD CROSSING


9. ROAD CROSSING - Light traffic
The following method should be used when it is necessary to erect spans of dropwire over roads.

In this method the dropwire span is erected by the one man installer using the dropwire dispenser and two sashlines.
The short sashline is passed over a wiring pulley at one end of the span and both ends secured to the pole belt near the ground. A long sashline is suspended from another pulley at the other end of the span and its short end passed through the guide on the dispenser and securely attached to the dropwire as close as possible to the drum on the dispenser. The longer end of the sashline is then laid out on the ground to the point where the short sashline was tied off.

The long sashline is securely attached to one end of the suspended short sashline and when traffic conditions permit, the running end of the short sashline is pulled up to raise the joined lines clear of the road. The dropwire is then pulled across from the dispenser by means of the sashline until there is sufficient for its termination. The sashline should be secured and the tension maintained on the dropwire by the dispenser until the dropwire clamps are fitted.

Full details of the method are given in Tables 2, 3A and 3B.

TABLE 2
PREPARATORY WORK FOR ERECTION OF DROPWIRE SPANS OVER ROADS LIGHT TRAFFIC

 

TABLE 3A
ERECTION OF DROPWIRE SPANS OVER ROADS WHERE THERE IS GOOD VISIBILITY FROM THE POLE END OF THE SPAN


 

FIG. 4


 

TABLE 3B
ERECTION OF DROPWIRE SPANS OVER ROADS WHERE THERE IS GOOD VISIBILITY FROM THE HOUSE END OF THE SPAN


10. MULTI SPAN JOBS - (up to 3 spans including span to the house)

NO SERIOUS OBSTRUCTIONS IN LINE OF ROUTE

NO CROSSINGS OVER POWER

NO ROAD CROSSINGS

  1. Pull sufficient dropwire off the dispenser for the lead in and attach dropwire clamp at the estimated position of the bracket at the house end. Climb ladder and attach clamp to bracket.

  2. Take ladder, tool basket and pulley to the first pole and erect ladder return to the house end for dispenser.

  3. Release the braking action of the dispenser so that the drum revolves freely. To introduce the necessary number of twists into the span length rotate the whole dispenser by the carrying handle a number of times, (approximately on twist for every five yards of span.) Payout the dropwire towards the first pole.

  4. At the first pole put the dropwire through a pulley, dropwire and attach the pulley to the handle of the tool basket.

  5. Climb pole with hand line in belt and fasten safety belt.

  6. Pull up basket, pulley and wire.

  7. Tension first span and attach dropwire support or clamps using dropwire support at straight through position or clamps at angle poles.

  8. Descend pole and take ladder to next pole.

  9. Return to dispenser and put twists into dropwire as (iii) above. Payout dropwire to next pole.

  10. Repeat (iii) to (ix) until the spans have been erected.

  11. Tension final span and terminate.


11 MULTI SPAN JOBS - (up to 3 spans including span to the house).

ROAD CROSSING

(a) If Road Crossing is in First Span from House.

  1. Place the dropwire dispenser at foot of serving pole and erect span as in Table 3B.

  2. At house end pull through sufficient dropwire for lead in and termination.

  3. Attach dropwire to house bracket using dropwire clamp.

  4. Proceed to serving pole, tension span and attach dropwire clamps.

  5. Take ladder to next pole on route.

  6. Return for dropwire dispenser and proceed along the pole route as in (10) (iii) - (xi).

(b) If Road Crossing is in Second Span from House;

  1. Place the dropwire dispenser at the foot of the second pole from house. ie the pole on the far side of the road crossing from the house. Suspend the long sashline from a pulley and attach the short end to the dropwire close to the drum. Neatly stow the long end at the foot of the pole.

  2. Suspend the medium sashline from a pulley at the serving pole. Neatly stow the long end at the foot of the pole.

  3. Fix the bracket at the house and suspend the short sashline from a pulley.

  4. Return to the Second Pole and lay out the long sashline across the road, to the intermediate pole, attach the long sashline to the medium sashline and pull through the surplus line.

  5. Continue laying out the sashline and tie it to the short sashline at the house. Pull through the surplus line.
    NOTE. Keep slack to a minimum to minimise pulling up time.

  6. When traffic conditions permit pull up both spans in one operation and pull over sufficient dropwire for lead-in and termination.

  7. Tension spans and attach dropwire clamps (or dropwire supports at through positions).

  8. Complete the remaining span as in (10) (iii) - (xi).


12 MULTI SPAN JOBS - (up to 3 spans including the span to the house).

ROAD CROSSINGS. Pulling up position at Distribution Pole end.

(a) If Road Crossing is in First Span from DP

  1. Place dropwire dispenser at foot of pole on the route side of the road crossing and erect the span to the DP as in Table 3A.

  2.  Attach the dropwire to the DP using a dropwire clamp and terminate on block. Place pole belt at the top of pole and secure rope.

  3. Proceed to second pole, tension dropwire and secure with dropwire clamps or dropwire support if at a straight through position. Attach pole belt at the bottom of pole and attach sashline.
    iv) Complete the erection of the remaining spans as in (10) (iii) (xi). The last span should be tensioned from the serving pole, not from the house bracket.

(b) If Road Crossing is in Second Span from DP

  1. Place dropwire dispenser at foot of the pole on the far side of the road from the DP and suspend a long sashline from a pulley and attach the short end to the dropwire close to the drum. Neatly stow the long end near the foot of the pole.

  2. Suspend the medium sashline from a pulley at the intermediate pole. Neatly stow the long end near the foot of the pole.

  3. Suspend the short sashline from a pulley at the DP. Secure the ends temporarily.

  4. Return to the dispenser position and lay out the sashline along the route of the first span. Attach the sashline to the prepared sashline at the intermediate pole and pull through the surplus. Continue to lay out the sashline to the DP and attach it to the short sashline. Pull through the surplus line and when traffic conditions permit erect both spans in one operation.
    NOTE. Keep slack to a minimum to reduce pulling up time.

  5. Tension spans and attach dropwire clamps (or dropwire supports at through positions).

  6. Complete the erection of the remaining span as in (10) (iii) (xi). Tension from the pole not the house bracket.
    NOTE. If suitable pulling up position with good visibility of the road crossing cannot be obtained the job should not be attempted by a man working unaided.

13. OBSTRUCTIONS IN LINE OF ROUTE
Where there are obstructions under the final position of the span the dropwire should be erected as described in the preceding paragraphs for road crossings. The sashline should be laid over the obstruction, carefully avoiding such obstacles as scrolls on metal gates which would subsequently catch the sashline. Where a car forms the obstruction and the owner is not available to move it, carefully lay the sashline over it ensuring that the sashline will not foul wing mirrors, gutters or bumpers when pulled up. The sashline should be rolled into a ball and thrown over obstacles such as trees or high fences, taking care to avoid throwing the line into a road or where it might hit other people. Avoid draping the sashline in such a way that it will be caught up by pedestrians or vehicles.

14. CROSSINGS OVER POWER
Crossings over power wires are tackled in the same way as road crossings except that one end of the long sashline should be rolled into a ball and thrown over the power line. Take care not to throw the line into a road or where it might hit other people. Ensure that the dispenser tensioning device is adjusted to maintain sufficient tension on the dropwire to prevent it sagging onto the power line while being drawn into position. Do not attempt power crossings unaided where the sashline would hang into a road.

See A2 E5503 for limitations on the erection of Post Office wires in the vicinity of power wires.

15. BRACKET-TO-BRACKET SPANS
If it is found necessary to tension dropwire spans from the bracket end, e.g, building to building spans:-

  1. Erect the dropwire using one of the methods in the preceding paragraphs and pass it through the pulley attached to the serving bracket so that the span can be tensioned and secured temporarily by the installer working on the ground.

  2. Fit the clamp or clamps to support the span.

16. MAINTENANCE OF DROPWIRE DISPENSER AND PULLEYS
To facilitate adjustment of the braking action of the dispenser the large thread on the spindle and the ends of the spring should be smeared with grease. The lock of the dispenser and the bearings of the pulleys should be lightly oiled.

Before use check that the dispenser and the pulleys are in good working order and free from cracked welds or broken parts. Check particularly the condition of the chain and catch on the pulleys.

17. SASHLINES
To reduce springiness and the tendency to twist and kink new sashlines should be pre-stretched by tying to a convenient fixed object and pulling hard on the other end.

This operation should be repeated at not less than 3 monthly intervals to ensure that the line has not been severely weakened by wear or rotting.

It is quite easy to apply a pull of about 100lbs which is several times the maximum reached in normal use. Be ready in case the line breaks. Inspect the line for wear, indicated by broken or frayed strands.

If there is any doubt about the condition of the tine change it at once.

NOTE. Substitutes should not be used in place of sashline No. 2. Most of the plastic lines which are available are liable to kink and do not lie flat on the road surface.
 


 

 
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