WORKING AT HEIGHT

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					WORKING AT
  HEIGHT
    WORKING AT HEIGHT
 The  majority of work in the
 construction industry is carried out
 above ground level. Some of this
 work can be done at a normal
 working height of up to 1.5m without
 the assistance of steps and ladders.
 It is therefore a fair assumption that
 at some time in your working life you
 will be required to work at height
 above the normal working height
There are various types of equipment that
 can assist you when required to work at
                 height

These are:-
 Hop-up working platforms

 Split head type working platforms

 Step ladders and ladders

 Trestle scaffolds

 Tower scaffolds

 Tubular scaffolds
               Hop-up working platforms

   This type of working platform is in the form of steps and is
    purpose made by a carpenter. It is normally made from
    softwood boarding or plywood.
   The overall width of this working platform can vary but is
    usually 400-450mm wide. The height can also vary but
    normally it is approx. 500mm high. The top which is used
    as the working platform should be at least 500mm square.
   When two of these platforms are used and spanned by
    scaffolding boards or staging boards the working platform
    area is increased and a much greater area can be covered
    without moving it.
   This type of working plat form is intended to provide a
    working platform up to approx. 2.4m in height without
    stretching.
      Split head type working platforms
    Metal split heads support timber joists and
  scaffolding boards and provides a continuous
platform for on ceilings. The height of the platform
is from 700 mm to 2.6m and can be extended to
  a height of 4.5mSplit heads are supported on
   a tripod base. A pin and hole method is used
   for main adjustment; fine adjustment can be
          achieved by using a screw jack.
Erecting Split heads


    A minimum of four units must be used to support the
  working     platform; eight or more split heads are used to
  board out larger areas.

     The height of each unit must be adjusted so that all
  units are level.

      The supports must be upright and placed on an even
  floor.


     It is placed on the split heads as near as possible to
  the walls to obviate the risk of the worker falling off the
  edge.
                   Step ladders
   These are used for internal work but can used outside if
    there is a firm base to stand the on.
   These ladders are manufactured in timber and aluminium
    and various sizes and heights.
   They consist of a set of stiles supporting flat steps at
    approximately 250mm centres. A back supporting frame is
    hinged to the top and secured at the bottom with a cord or
    a metal locking bar. When the steps are extended the
    locking bar ensures the correct working angle and prevents
    the steps from collapsing.
   These steps can be used in pairs and a board inserted to
    provide a wider working area.
   Timber step ladders are susceptible to damage, warping
    and twisting where as the aluminium type stepladders are
    much lighter and stronger as well as rot proof.
   These ladders must not be used if they are broken or
    damaged or have be repaired or have missing parts.
                     Step ladders
       Timber step ladders must not be painted as
        this may hide defects
       Aluminium ladders must not be used near
        overhead electric power lines.
       On finding defects a “ DO NOT USE” notice
        must be displayed and the defects reported
        as soon as possible to your supervisor.




Single step ladder             Step ladder used in pairs with board
                     Ladders
   Ladders are used to gain access to
    scaffolds or light work at high levels. They
    are made from either timber or aluminium
    and are available in length ranging from
    3m up to 7m in length.

   There two types of ladders :-
        Single section ladders
        Multi – section ladders
           Single section ladders
   These ladders are often called standing ladders and are available in timber
    or aluminium.
   Timber standing ladders are made from Douglas fir, redwood, white-wood
    or hemlock.
   The rungs are round or rectangular and have steel tie rods fitted
    underneath every eighth rung and under the second rung from each end
    of the ladder. The stiles are reinforced with braided wire housed in a
    groove and clipped to the underside of the stile.
   The aluminium standing ladders are made of aluminium alloy. They are
    lighter than the timber version, very strong, rot proof and will not twist,
    warp or burn.
   The rungs must be non- slip and are usually spaced at 230mm or 250mm.
   The stiles are often fitted with ladder feet, which are either a non-slip
    serrated rubber block or suction pads.
   There is another version of this single section type of ladder called a pole
    ladder. This ladder is a timber ladder with stiles, which are made from one
    straight tree trunk cut down the middle. His ensures even strength and
    flexibility. This type of ladder is available up to lengths of 12m and is used
    on site to gain access to tubular scaffolding
          Multi -section ladders
   These types of ladders are called extension ladders. They
    can be double or triple according to the number of sections
    they are comprised of. They are fitted with latching hooks
    to the bottom of the extension section and guide brackets
    are fitted to the top of he lower section. The latching hooks
    locate over the rung of the section below when extended
    and the guide bracket keeps the section together.
   The extending section can lifted in place manually or by a
    rope and pulley system. This system is usually fitted to the
    longer ladders.
   The rungs must be non- slip and are usually spaced at
    230mm or 250mm.
   The stiles are often fitted with ladder feet, which are either
    a non-slip serrated rubber block or suction pads.
   The length of these ladders vary from 3m to 7m when
    closed and extend to up to 19m
TYPES AND SIZES OF LADDERS
Standing ladders:
 Single section ladders up to 7.3 m long.


Double extension ladders:
 Two sections similar to standing ladders with
  position for coupling them together.
 Without ropes: up to 4.9 m long when closed,
  extending to approximately 9 m.
 With ropes: up to 7.3 m long when closed,
  opening to approximately 12 m.
TYPES AND SIZES OF LADDERS
Triple extension ladders:
 Similar to double extension ladders but, with
  three sections. Without ropes: up to 7.3 m long
  when closed, extending to approximately 19m.
 With ropes: up to 3 m long when closed,
  extending to approximately 7.5 m

Pole ladders:
 Single section ladders with the stiles made from
  one straight tree trunk cut down the middle. This
  ensures even strength and flexibility.
  Obtainable up to 12 m long and used mainly for
  access to tubular scaffolding.
                      Parts
Stiles
 Usually made from Douglas fir, whitewood,

  redwood or hemlock.
 The stiles of pole ladders are made from

   whitewood.
Rungs
 Round or rectangular, made from oak, ash

  or hickory
                         Parts
Ties
 Steel rods fitted below the second rung from each end, and
  at not less than 9 rung intervals. Ties can be fitted under
  every rung.

Reinforcing wires
 Give ladders extra strength. Galvanised wire or steel cable
  is fitted and secured, under tension, into grooves in the
  stiles.

Ropes
 Hemp sash cord or a material of equivalent strength. Ropes
  of man made fibre must provide adequate hand grip.
 Guide brackets Fitted at the top of lower sections to keep
  the sections together.
                          Parts
Guide brackets
 Fitted at the top of lower sections to keep the sections
  together.

Latching brackets
 Fitted to the bottom of extension sections to hook over a
  rung of the section below.

Pulley wheels
 Guide and facilitate the smooth running of

  the ropes of rope operated ladders.
         SAFETY CHECK LIST
   Ladders should NOT be used if they have any of the
    following defects:
    - broken, missing or makeshift rungs.
    - broken, weakened or repaired stiles.
    - broken or defective ropes, guide brackets, latching hooks
    or pulley wheels.
   Ladder timber must be:-
    - straight grained.
    -free from knots greater than 6 mm in diameter, and from
    resin pockets.
    - free from splits, checks and decay.
   Rungs must be clean - and free from dirt and grease.

    REMEMBER! DO NOT PAINT timber ladders, paint
                  can hide defect
     ALUMINIUM LADDERS

   Aluminium ladders are made out
    of aluminium alloy.
    They are lighter than timber ladders,
    very strong, rot proof and will not twist,
    warp, burn or rust.
   The rungs must be non slip, at 230 mm
    or 250 mm intervals.
   Both ends of each stile must be closed
    with replaceable blocks of hardwood or
    other non slip, non metallic material.
 Aluminium Swing back Steps
   Made of aluminium alloy. They are lighter than timber steps, very
    strong, rot proof will not twist, warp or bend.
   The treads are not less than 76mm deep and must be non slip
    and horizontal when the steps are open. The working top is not
    less than 100mm deep.
   The back is attached with a single hinge extending the full width
    of the back.
   The locking bar clips in place when fully opened.
   The feet are made of a non – slip material.

Sizes
 These steps are sold by the number of treads. Common sizes are
   listed below.
                  Working height when open
                      6 treads …….. 1.4m
                      8 treads ……... 1.8m
                      10 treads …….    2.3m
                      12 treads …….. 2.8m
Aluminium Swing back Steps
   SAFE USE OF LADDERS
Raising and lowering ladders
 Ladders are raised with the section
  closed.
 Extension ladders with long sections
  are raised one section at a time and
  are slotted into position before the
  ladders are used.
 TWO people are required to raise and
  lower heavier type ladders.
      The following is a step by step procedure
             for raising heavier type ladders.
 lay the ladder flat
 One person stands on the bottom rung of the ladder. He/she holds
  the stiles to steady the ladder when it is being lifted.
 The second person stands at the top of the ladder. He/she lifts the
  ladder over his/her head and moving hand over hand, walks
  towards the foot, raising the ladder as he/she goes. This is
  continued until the ladder is upright.
 When erected, the correct safety angle is 75degrees or a ratio of 4
  up to 1 out.
 To lower the ladder from the upright position, the above process
  is reserved.
 Lighter ladders may be raised by one person but the bottom must
  be placed against a firm stop before lifting is commenced.
REMEMBER ! Ladders must extend 5 rungs ( 1.070 m ) above
                         the working platform
          TYING LADDERS
 The Appropriate Regulations state that
  ladders must have a firm and level base
  on which to stand, and if over 3m long,
  they must be fixed: at the top, or if this is
  not possible at the bottom.
 If neither way is possible, a man must
  ‘foot’ the ladder, that is, stand with one
  foot on the bottom rung, the other firmly
  on the ground. He must hold both stiles
  and pay attention all the time.
 This prevents the base from slipping
  outwards and the ladder from falling
  sideways
                 LASHINGS
 Wire lashings should be used in preference
  to fibre rope.
 Lashings should always be to the stiles
  and never to the rungs.
 Lashings must be tied to secure positions,
  such as scaffold tubes or screw-eyes
  which have been firmly screwed into the
  fascia or wall.
 Special ladder clips can be used if
  available

See Next Slide
NEVER! Tie lashings to pipes or gutters.
       LIFTING AND CARRYING
              LADDERS

   To lift and carry ladders over short distances rest
    them on the shoulder, and lift them on the
    shoulder, and lift vertically by grasping the rung
    just below normal reach.
   The correct balance and angle must be found
    before moving.
   When moving ladders more then a few metres,
    they should be lowered and carried on the
    shoulders by TWO men, one on either end.
Overlap of extension ladders
The minimum recommended overlap
on extension ladders is:-
– 2 rungs for ladders with closed length
  up to 4.8 m
– 3 rungs for ladders with closed length
  up to
  6m
– 4 rungs for ladders with closed length
  over
  6 m.
                SAFE WORKING
   Ladders must extend 5 rungs ( 1.070 m) above the
    working platform unless other equivalent hand hold is
    provided.

   NEVER    stand ladders on uneven, soft, or loose ground.
   NEVER    support a ladder on a fragile surface.
   NEVER    stand a ladder on a box, drum, or other unsteady
    base.
   NEVER    use a makeshift ladder.
   NEVER    use a ladder which is too short.
   NEVER    climb ladders with slippery, icy, or greasy rungs.
   NEVER    wear soft soled shoes or footwear with slippery
    soles.
   NEVER    try to carry too much equipment up a ladder.
   NEVER    over reach when working on a ladder.
                                 REMEMBER !
Take care when raising to avoid overhead obstructions, such as electric cables
          Always ! ensure the ladder is at the correct angle of 750 ( 1 in 4)
          and projecting above the working platform by at least 1.070 m
          and be securely fixed.




Overnight safety - ladders should be
 lowered and stored in a safe place overnight.
If this is not possible a scaffold board
 at least 2 m long should be firmly lashed
 to the rungs to prevent access.
           STORING LADDERS
   Always store ladders in a covered, well ventilated area,
    protected from the weather and away from too much
    dampness or heat.
   Never leave ladders leant against a wall or building.
    Ladders can fall if stored vertically, so take particular care.
    If possible, secure the top, with a bracket, for instance).
   Never hang a ladder vertically from a rung.
   Don’t store a ladder in any place where a child might be
    tempted to climb it.
   Storing horizontally, a rack or wall bracket are ideal.
    Always support them on the lower stile, supported every
    1m maximum.
   Keep wooden ladders clear of the ground to avoid contact
    with damp.
DEFECTS IN LADDERS
                       ACCESS
   It is usual to access a scaffold from a ladder and provision
    must be made so that this can be done easily and safely.
   A suitable gap should be left in the handrail and toe board
    arrangements to allow operatives to access the scaffold, the
    ladder which should be secured both at the top and bottom
    should extend at least 1.050 m ( 5 rungs) above the
    platform.
   The final rung of the ladder from which the operative steps
    onto the platform should ideally be just above the surface
    of the platform.
         FOLDING TRESTLES
   Folding trestles are made of softwood similar to
    ladders and are also made of aluminium alloy.
   They are tapered towards to top and should be
    wide enough to take two 230 mm scaffold boards
    or one staging board.
   Cross bearers are staggered on either side to
    give a platform rise of 230 mm to 260 mm.
   Each side of the trestle should have at least two
    tie bars fitted to give extra strength.
   The trestle is stopped from completely collapsing
    by a specially formed lipped trestle hinge.
   When the hinge is fully opened, the angle should
    not be less than 240 or more than 360.
SIZE
Trestles are available in sizes from
1.830m to 4.270m in height.
Some trestles are fitted with a special telescopic
device which extends them vertically
     SAFETY CHECK LIST
  Trestles should not be used if they
  have any of the following defects:-
 broken, missing or makeshift
  bearers.
 broken or repaired stiles (replaced
  stiles are acceptable)
 loose cross bearers ( the trestle must
  be rigid)
 broken, badly worn or loosely fixed
  hinges.
                            FOLDING TRESTLES




Trestle are use to form a quick lightweight working platform. To do so two set of trestles
          are used in conjunction with scaffolding boards or lightweight staging.
      However the distance in between the two trestles is restricted because of the
 Scaffold board thickness. When staging or scaffolding boards are fitted there should be
   an overhang of not less than 50mm or more than 4 times the thickness of the board.
                                        Example:
If a staging board is 50mm thick the 4 x 50mm equals 200mm maximum overhang
      SCAFFOLDING BOARDS
   All scaffold boards should be made to British
    Standard specifications or they should be
    ‘specials’
   To prevent boards from splitting, the ends should
    be bound with a galvanised metal band.
   Sometimes the board ends are cut at an angle to
    reduce the risk of damage
                       SIZES.
  Boards are rarely longer than 4 metres, and thickness is
  related to length as follows:-

      Boards 40 mm thick should not exceed 2.750 metres in
  length.
      Boards 51 mm thick should not exceed 3.000 metres in
  length.
      Boards 75 mm thick should not exceed 4.000 metres in
  length.

The width of boards is also affected by the thickness:-
       Boards less than 50 mm thick must be at least 200
  mm wide.
       Boards thicker than 50 mm can be 150 mm wide.

Maximum span between supports
     - Boards 40 mm thick 1.520
     - Boards 51 mm thick 2.590
     SAFETY CHECK LIST
Scaffold boards must be:-
  – made from straight grained timber
  – free from knots and shakes
  – free from decay
  – clean and free from grease and thick
    paint, etc.
  – Scaffold boards must not be twisted or warped
    or have split ends
    LIGHTWEIGHT STAGINGS
 Lightweight stagings provide platforms for
  spanning greater lengths than scaffold
  boards.
 They can be used without intermediate
  supports on trestles and ladder brackets,
  and directly on to roof trusses without
  other support.
 The stagings are designed to take a
  maximum load of three men together with
  lightweight equipment of up to 272 kgs
  evenly supported.
  LIGHTWEIGHT STAGINGS
Sizes
 450 mm wide, in lengths of from
  1.8m to 7.3m
Stiles
 Should be reinforced with galvanised
  high tensile steel wire, and the ends
  of stiles
 should be protected with hooping
  irons
  LIGHTWEIGHT STAGINGS
Cross supports
 Must be fitted every 300 mm or 450 mm
  centres along the length of the staging
  and reinforced with steel tie rods.
Metal tie rods
 These must be fitted under every cross
  support.
Slats
 Every slat is double screwed to the end
  and middle cross rail.
LIGHTWEIGHT STAGINGS
LIGHTWEIGHT STAGINGS
     SAFETY CHECK LIST

Lightweight stagings must have:
 straight grain timber for stiles,
  cross supports and slats.
 timber free from knots, shakes,
  resin pockets and decay.
 sound tie rods fitted under each
  cross support
 sound and firmly reinforcing wire
 rust free metals.
AJUSTABLE METAL TRESTLES
 Adjustable metal trestle scaffolds, they
  are widely used by all trades to provide
  working platforms up to 3m in height in
  confined spaces.
 Guard rails and toe boards are not
  normally required unless the platform
  exceeds 2m in height.
 They have the advantage over other forms
  of scaffold in that they are quickly and
  easily erected and dismantled.
 Various British Standards and
  Construction Regulations cover materials,
  design widths of platforms and loadings.
AJUSTABLE METAL TRESTLES
GROUND BASE CONDITIONS
 All trestle and hop ups scaffolds
  should have a firm level base.
  Sufficient to support the required
  loading.
 Hazards to look for when erecting
  and dismantling these scaffolds are:-
         Overhead cables
         Soft spots in ground
  conditions.
POSITIONING OF TRESTLE

 Trestles are positioned to suit batten or
  staging thickness.
 Boards normally used on sites are 225
  mm x 38 mm x 3900 mm which should be
  supported every 1.5 m for British
  Standard Boards or 1.2 m for others.
 Some patented staging can span up to
  3m.
      TOWER SCAFFOLDS
  There are two kinds of tower scaffolds.
  They can be either :
 Static – Stationery, remains in one place
  cannot be moved.
 Mobile – Can be moved to different
  location when needed
 Both kinds of tower scaffold can :-
 Tailor made - for a particular job and
  constructed insitu ( inplace )
 Proprietary – made by a manufacture
  with standard sections which fit together
          Static tower Scaffolds
   This type of scaffold is constructed from individual tubular
    scaffold components. These components are secured using
    standard scaffolding clips. The tower is constructed square
    in shape using tubular steel standards and strengthened by
    braces and ledgers.

   Access to the tower may be from the inside or outside of
    the tower, but care must be taken to ensure the tower is
    not destabilised by leaning ladders from the outside as the
    tower may topple.

   Scaffold towers should be designed to carry a load of
    150kg/m² spread over the whole working platform in
    addition to its own weight.

   A special design will be required for any tower which may
    be subject to extra loadings from wind or extra loading on
    the working platform.
TOWER SCAFFOLDS ( STATIC )
              TOWER SCAFFOLD
               REQUIREMENTS
   Tubes must be straight.
   Tubes and fittings must be undamaged and free from
    corrosion.
   The ground tower is to place on must be firm and even.
   Base plates must be used.
   Adjustable base plates can be used on ground, which has
    different levels.
   Sole plates must be used to provide even weight
    distribution if the tower is to be used on soft ground.
   Couplers must be load bearing.
   Horizontal members must be fixed to uprights with the
    exception of transoms under the working platform.
   Towers must have diagonal and plan bracing built in.
   Foot ties or plan bracing must be fitted as low as possible.
             TOWER SCAFFOLD
              REQUIREMENTS
   Working platforms must be close boarded.
   Overhang boards must not exceed four times the thickness
    of the boards and must not be less than 50mm past the
    support.
   Working platforms above 2m high must have toe boards
    fitted at least 150mm high.
   Working platforms above 2m high must have guard rails
    between 920mm and 1150mm high.
   Access ladder must be lashed vertically, preferably on the
    inside of the tower.
   The minimum base measurement for any tower is
    1250mm.
   Indoors the height of any tower must not be greater than
    three and a half times its smallest base measurement.
   Outdoors the height of the tower must not be greater than
    three times its smallest base measurement.
   Towers higher than 6.4m must be tied to the building or
    have adequate counterweights fitted.
 ALWAYS  us towers on firm even
 ground – NEVER on sloping ground.

 NEVER  place steps on the working
 platform

 NEVER‘sheet out’ a tower
 DANGER !! beware of overhead
 wires and cables when working
           from towers
TOWER SCAFFOLDS ( MOBILE )
    MOBILE TOWER SCAFFOLDS
         REQUIREMENTS
   Tubes must be straight.
   Tubes and fittings must be undamaged and free from
    corrosion.
   Castors must only be fitted to standards.
   Castors must be of a swivel type fitted with a locking
    device.
   Castors must fitted by a method which prevents the wheel
    from falling out if not in contact with ground.
   Couplers must be load bearing.
   Horizontal members must be fixed to uprights with the
    exception of transoms under the working platform.
   Towers must have diagonal and plan bracing built in.
   Foot ties or plan bracing must be fitted as low as possible.
   Working platforms must be close boarded.
    MOBILE TOWER SCAFFOLDS
         REQUIREMENTS
   Overhang boards must not exceed four times the
    thickness of the boards and must not be less
    than 50mm past the support.
   Working platforms above 2m high must have toe
    boards fitted at least 150mm high.
   Working platforms above 2m high must have
    guard rails between 920mm and 1150mm high.
   Access ladder must be lashed vertically,
    preferably on the inside of the tower.
   The minimum base measurement for any tower is
    1250mm.
   Indoors the height of any tower must not be
    greater than three and a half times its smallest
    base measurement.
 MOBILE TOWER SCAFFOLDS
      REQUIREMENTS
 Outdoors   the height of the tower
  must not be greater than three times
  its smallest base measurement.
 Towers higher than 6.4m must be
  tied to the building or have adequate
  counterweights fitted.
    MOBILE TOWER SCAFFOLDS
         REQUIREMENTS
   ALWAYS us towers on firm even ground –
    NEVER on sloping ground.
   ALWAYS ensure that there are no hoes or
    obstructions on the ground which could foul the
    wheels.
   ALWAYS move a tower by pushing at the base
    NEVER pull along from the top
   NEVER move a tower with men or equipment on
    it.
   NEVER place steps on the working platform
   NEVER ‘sheet out’ a tower
     DANGER !! beware of overhead wires and
          cables when working from towers.
         PROPRIETARY TOWER
             SCAFFOLDS
   These tower scaffolds are useful for light work of
    a short duration such as painting and decorating
    a building both inside and outside.
   This scaffold should only be used where the
    ground is sufficiently firm, level and smooth to
    maintain stability.
   All wheels must be the lockable type and kept
    locked when the scaffold is in use.
   The scaffold should only be moved by exerting
    force on the bottom of the tower and never
    pulled from the top.
   Towers should never be moved with persons still
    in them
             OUTRIGGERS

 If extra working height is required, then
  the base measurement can be increased
  by the use of outriggers.
 These are tubes or special units that
  connect to the bottom of the tower at the
  corners, giving more overall base
  measurements
 Outriggers also help to stabilise a scaffold
  tower and are usually used for this
  purpose as well as giving extra working
  height
          Tubular Scaffold
    There are two main types of tubular
    scaffolds :

   Independent Scaffold
   Dependent or Putlog Scaffold
       Independent Scaffold
 This is a scaffold which, apart from the
 necessary ties stands completely free of
 the building.

The main applications for this scaffold are:-
   Access for stonework on masonry
  buildings.
   Access to solid or reinforced concrete
     structures.
   Maintenance and repair work.
   Cladding work.
          Independent Scaffold
   This scaffold consists of two rows of standards
    joined together by ledgers, which in turn are
    joined by transoms.
   The standards must always be upright and
    slightly towards the building.
   The inner row must be as near to the building as
    possible for painting and never more than
    375mm away from the wall to accommodate a
    single scaffold board which is placed on the
    protruding transom. This should extend to within
    50mm of the face of the wall
   Transoms may extend beyond the inner standard
    to support one or two boards between inner
    standards and the wall.
           Independent Scaffold
   It is essential to include cross bracing at every lift
    to ensure rigidity.
   Only load bearing couplers should be used
    between the standards and ledgers and on
    through ties.
   The ground should be firm and level and base
    plates should be used under every standard.
   If this scaffold is to be placed on soft ground then
    wooden sole plates 225mm x 38mm thick should
    be used.
   Although it is called an independent scaffold it
    does consist of normal ties for its stability.
   Usually this scaffold is tied through door and
    window openings where convenient
TUBULAR SCAFFOLDS
Independent Scaffold
Dependent or Putlog Scaffold
   This is more commonly known as a ‘Putlog’ or ‘Bricklayers’
    scaffold.
   It is similar to the independent access but has only one row
    of standards, with the inner row replaced by the brickwork.
   This means that the inside ledgers and ledger bracing are
    not required.
   The remaining scaffold functions in the same way as the
    independent scaffold.
   The scaffold can be erected to existing brickwork, but in the
    main this type of scaffold is erected along with new building
    work.
   The platform is supported by putlogs in this type of scaffold
    and not transoms.
   The putlog is supported by the new brickwork by allowing
    the spade end of the putlog to rest flat on the brickwork.
Remember!! Although the putlog is fixed into the wall it does
  not act as a tie for the scaffold.

   They should be tied to the building at least every 4 m vertically
    and 6m horizontally.
   When the scaffold has to pass a window a bridle tube will have to
    be used.
   The bridle tube acts in the same way as a ledger and is erected
    where an opening in the brickwork does not allow the putlog to be
    fixed to the wall.
   When installed, the bridle should be supported at intervals equal
    to the maximum bay space of the scaffold erected and when
    connected to the underside of the putlog, the connections must be
    with the right angled couplers
   Where the window is greater than the bay space of the scaffold,
    the centre of the bridle can be supported by a standard, which is
    conveniently situated inside of the building.
                     Access
   It is usual to access a scaffold from a ladder and
    position must be made so that this can be done
    easily and safely.
   A suitable gap should be left in the handrail and
    toe board arrangement to allow operatives to
    access the scaffold, the ladder which should be
    secured both at the top and bottom should
    extend at least 1.05 m ( 5 rungs approximately)
    above the platform.
   The final rung of the ladder from which the
    operative steps onto the platform should ideally
    be just above the surface of the platform.
   The gap left between the ladder and the guardrail
    should not be more than 500 mm.
    Guardrails and Toe boards
 Access platforms more than 2m high must
  have guardrails and toe boards.
 The risk of falling materials causing injury
  should be minimised by keeping platforms
  clear of loose materials.
 In addition provide a way of preventing
  materials or other objects rolling, or being
  kicked, off the edges of working platforms.
 This can be achieved by fixing toe boards,
  solid barriers, brick guards, or similar at
  open edges.
Guardrails and Toe boards
        Working Platforms
 This is the level at which the work will be
  carried out.
 The loading of materials must be spread
  as evenly as possible.
 Working platforms must be kept free from
  ice, snow, grease or other hazards.
 Gaps between boards should be kept to as
  small as possible and to achieve this the
  scaffolder must properly measure the
  distance between standards, to enable a
  correct and tidy scaffold width.
Widths of platforms for the different
     trades are shown below
Working Platforms
        Working Platforms
 Boards must be at least 150 mm wide if
  they are 50 mm thick, 32 mm and 38 mm
  boards must be at least 200 mm wide.
 Boards must rest evenly on their supports.
 No board must project more than 4 times
  its thickness beyond its end support, or
  less than 50 mm.
 No knot or group of knots must exceed 50
  mm diameter.
 All board ends should be bound with hoop
  iron.
 Split or damaged boards must not be
  used.
Tubular Scaffolding Fittings
            Swivel Coupler
            Connects two scaffold tubes at any angle.
            90 Right Angled or Double Coupler
            Connects two scaffold tubes at right angles.
             Used to connect ledgers to standards.
            Putlog Coupler
            Used to connect putlogs to ledgers and to fix
             handrails. These couplers are non-load
             bearing.
            Putlog End
             A flat ended fitting which can be attached to
             the end of a tube to convert it into a putlog.
            Joint Pin or Expanding Spigot
            An internal fitting for joining two vertical
             scaffold tubes end to end.
            Sleeve Coupler
            An external connection for joining two scaffold
             tubes end to end under tension. Eg ledger and
             bracing
Tubular Scaffolding Fittings
              Base Plate
              A steel plate used to distribute the load
               to standards.
              Adjustable Base Plate
              A base plate fitted with a screw jack for
               use on uneven ground.
              Toe Board Clip
              Used to fix toe boards to a standard
              200mm Castor Wheels
              Used for mobile towers. They can be
               rubber or steel and fitted with a locking
               device.
              Gin wheel
              Used for raising and lowering equipment
               from scaffold. A swivel ring at the top of
               the wheel fits over the tube for
               maximum safety.
              Adjustable reveal pin
              Used to tighten a tube between two
               opposite surfaces such as a window
               reveal, or to tie a scaffold to a building

				
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