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POCHIN CONCRETE PUMPING

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					                                                                                         PCP/ RA/ 01
                                                                                         Revision 2
                                                                                         May 2007
                                                                                         Page 1 of 3

                  Significant Risk Identification/ Control Measure Statement

                      TRUCK MOUNTED MOBILE CONCRETE PUMP

The mobile truck-mounted concrete pump is designed to convey concrete from a visiting truck-
mixer to a point designated by the hirer. This is achieved via a hydraulically powered pump,
through steel pipe sections attached upon an articulated boom, to a flexible rubber delivery hose
or ‘tremmie’ pipe attached to the end of the boom.
The boom may also be used to feed additional flexible hoses, or a fixed pipeline laid out at the
appropriate surface level – but these must not be supported or lifted by the boom.

All POCHIN Concrete Pump Operators (CPO’s) are issued with a detailed Operators Procedure
Guide.
Every CPO holds a current CPCS (Construction Plant Competence Scheme) card (or equivalent)
for concrete pumping operations, many have attained NVQ Level 2 qualification.
CPO’s are assessed periodically, and are also subject to safety ‘spot checks’, in order to ensure
operating standards are maintained, and developed.

All machines are serviced at nine-weekly intervals by skilled fitters, and are also subject to annual
thorough examination of the placing boom.

Data sheets, detailing pump dimensions, outrigger loadings/ positioning, boom type/ reach, and
pumping delivery pressures/ volume outputs are available upon request from POCHIN Concrete
Pumping, or via the POCHIN website – www.pochins.plc.uk/construction

As an overview, the significant risks that are present in respect of concrete pumping activities are
noted below, along with appropriate control measures.
(NB - specific risk assessments have been completed and are available for each element of the
pumping operation. The CPO carries these within the Procedure Guide)

Significant Risks

Overturning or collapse of the concrete pump (or part thereof):
 every machine has been tested for strength and stability when new, and following substantial
   alteration or repair;
 sufficient space must be made available to extend and lower the outriggers/ stabilisers, in
   accordance with the pump manufacturers instructions, before the boom is raised;
 it must be ensured by the hirer that the ground conditions are of sufficient bearing strength to
   support the imposed load of the pump – loading details are available on the data sheet, and
   are displayed on every outrigger;
 sole-plates/ pads are available with each pump, and positioned below the outrigger feet aid
   corner load dissipation; in certain circumstances it may be necessary to use extra support
   (usually timber blocks) under each foot - the hirer should consider and provide these;
 all hydraulic rams on the placing boom are fitted with lock valves which prevent the boom
   sections from falling should a hydraulic hose bursts;
 no person, other than the person guiding the placing hose, should be allowed to work under
   the boom.

General Pumping Operation:
 each machine is fitted with a remote control unit (RCU) which allows the CPO to operate the
   machine from a position of safety/ improved visibility;
 the RCU is fitted with an emergency stop control which when activated, immediately cuts off
   power to the pump and placing boom. Similar stop controls are also fitted around the pump;
 when the CPO is unable to see the tip of the boom or the concrete placing gang, the hirer is
   responsible for appointing a ‘banksman’ to give signals to the operator;
                                                                                          PCP/ RA/ 01
                                                                                          Revision 2
                                                                                          May 2007
                                                                                          Page 2 of 3

   when the CPO is required to operate the pump remote from the machine, the hirer must
    appoint a person to ensure that the correct concrete level in the concrete pump hopper is
    maintained;
   no person, other than the CPO shall be allowed onto the pump during its operation;
   during boom movements, the flexible delivery hose may swing freely - it is imperative that all
    persons remain at a safe distance during these movements;
   should a blockage occur (see below) the placing boom may also be affected, and could be
    subjected to an unplanned movement. The CPO will deal with this as noted in ‘blockages’
   a safety chain is fitted to every boom, designed to hold the reducer and placing hose if the
    connecting clip fails;
   operatives controlling the position of the placing hose should hold it at arm’s length; clear
    signals should be given to the CPO so that the boom can be positioned to facilitate the placing
    of the concrete

Air entrapped in the delivery line:
 should air be sucked into the pump/ delivery line, it could become compressed, and may be
    ejected forcefully from the end of the pipe-line;
 to control this, the correct level of concrete must be maintained in the pump hopper. Where
    practicable, this will be monitored by the CPO, however, where he is required to position
    himself remote from the pump, a competent person shall be appointed by the hirer to
    supervise the concrete level in the hopper and advise the CPO when the level becomes low;
 employees of the hirer must not uncouple pipes without the operator's permission.

Crushing of persons by reversing vehicles:
 normally the CPO will direct the driver of the truck-mixer during the reversing operation;
 any other person nominated to direct reversing truck-mixer drivers must be competent, and be
   instructed as to the correct procedure, and to potential risks;
 many POCHIN mobile concrete pumps are fitted with CCTV cameras at the rear; all POCHIN
   mobile concrete pumps are fitted with a warning bleeper which is activated when reverse gear
   is selected.

Blockages:
Occasionally, a ‘blockage’ may occur in the pipeline, for example:
 at the beginning of a pour, segregation may occur in the concrete aggregates as it is pushed
   through the pipeline with the primer;
 the concrete mix design or consistency is wrong or inappropriate;
 the concrete may have become stiff because it has been standing for too long;
 the flexible placing hose has become kinked, restricting concrete flow

To alleviate the likelihood of a blockage occurring, the following should be adhered to:
 it is essential that the correct concrete pump mix design is ordered - the CPO, through his
   experience, will recognise concrete that cannot be pumped - he will reject such loads;
 for ‘standing concrete’ the CPO shall if required/ practicable circulate the concrete in the
   hopper/ boom;
 the flexible delivery hose must never be kinked – it should be hung or laid ‘straight’;

Should a blockage occur, the CPO will stop the pump action and/ or reverse the pumping direction
without delay. The blockage may be freed almost immediately when he starts to pump again, but
the release is likely to cause the delivery hose and/ or boom to ‘kick’.

All persons should retreat to a safe position until the concrete is flowing freely. The risk area is a
circle whose diameter is twice the length of the delivery hose.

Bursting of pipe-lines under pressure:
 only approved supplier flexible delivery hoses, steel delivery pipes, and clips of a type suitable
   for the pressures likely to be encountered during concrete pumping shall be used on POCHIN
   concrete pumps;
                                                                                       PCP/ RA/ 01
                                                                                       Revision 2
                                                                                       May 2007
                                                                                       Page 3 of 3

   pumped concrete can cause harsh internal wear to pipes and hoses. Wear will be monitored
    visually by the CPO, and visually, ultrasonically, and gauge measured, by POCHIN fleet fitters
    during scheduled services. Any pipes which fall below acceptable thickness tolerances shall be
    replaced.

Overhead electricity cables and other obstructions:
 the absolute minimum distance that any part of the mobile pump including the boom, is
   permitted to be, relative to overhead electric distribution lines, is 6 metres. HOWEVER, this
   safe working distance shall be subject to any stricter requirements of the line owner, and the
   hirer shall remain responsible for ensuring that a safe system of work is provided (and
   implemented), for use of the pump in proximity to the overhead lines;
 where there may be a potential encroachment into the safe working distance by the boom, or
   where its use could result in damage from other existing structures or obstacles, it may be
   necessary to construct a ground level pipe-line to convey the concrete to the placement area ;
 consideration should be given where the pump boom has to be unfolded or folded up during
   the hours of darkness, due to reduced levels of luminance and visibility.

Contact with moving machinery:
 all moving machinery on the concrete pump is fully guarded either by its manufactured position
   or by mechanical guard;
 the rotating remix shaft and valve gear located in or to the rear of the hopper are guarded by a
   grille fitted with an automatic interlock system;
 all persons must stay clear of the mobile pumps outriggers/ stabilisers whilst they are being set
   out.
 all persons must be clear of the boom as it is unfolded/ folded

Cleaning and dismantling of a pipe-line:
 in exceptional circumstances, the CPO may have to use compressed air to clean out concrete
   from a pipeline;
 the CPO has a set procedure for this operation; other personnel shall only be involved under
   his strict direction.

Working at Height (on the pump):
 the CPO may be required to undertake certain maintenance tasks that will require him to work
  at height upon the mobile pump. Where there is the case, and there is a risk of fall, the CPO
  will be required to wear a safety harness, and use lanyards to restrain him in a position of
  safety.

Noise:
 noise assessments have been completed by POCHIN in respect of CPO position in proximity
   to the pump – these suggest negligible health implications for the CPO during normal
   operations;
 however, the added noise from site plant, especially vibrators and petrol drive units, may
   create an increase in noise levels. The hirer shall remain responsible for managing and
   advising upon this issue.

COSHH:
 cement/concrete – There is a potential of ‘burns’ if skin is exposed to wet cementatious
  products. POCHIN CPO’s are aware of this hazard, and are provided with appropriate PPE to
  aid protection against exposure.
 various other substances are in use on the pump, including grouts, oils, and greases – these
  are of lower hazard, however assessments have been completed, and CPO’s have been
  advised of the requirements for each.

MJ McGlone
Senior SHE Advisor
POCHIN Plant Limited
15 May 2007

				
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