Practical Alarm Management for Engineers and Technicians by xfr81871

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									CIBSE National Conference 2002 (Part 2)
24 October
Royal College of Physicians

Improving Commissioning Management



Introduction

Commissioning Management can be defined as an activity in which a specialist
company or individual, the Commissioning Manager, manages the commissioning
and testing process and integrates it into the construction of the overall project.

Commissioning Management was introduced into the building services industry in the
United Kingdom over ten years ago. Properly executed, Commissioning
Management adds Client value, mitigates risk and delivers working buildings more
fully supporting Clients’ business function. Part L2 of The Building Regulations under
Section 2 stresses the need for building services to be inspected and commissioned
in an appropriate sequence.

BSRIA, supported by the DTI, produced recently Application Guide 5/2002 titled
“Commissioning Management - How to achieve a fully-functional building”. Similarly,
the CIBSE have set up a task force to produce a Commissioning Management Code
and Commissioning Management is recognised now as an essential management
tool on many major construction projects. However, there has been limited feedback
within the industry of ways in which the Commissioning Management activity can be
improved.

This paper will make a further contribution to that feedback process. This will be
achieved by highlighting a range of specific problems that have been experienced on
major construction projects both in the UK and abroad. Suggestions will be offered
of ways in which these problems can be avoided or mitigated in order to improve the
Commissioning Management activity in the future.


Early Programming Involvement

The key to the successful engagement of a Commissioning Manager on a particular
project is early involvement. At the initial planning stages of the project, he is able to
provide realistic timescales for the pre-commissioning, commissioning, testing and
hand-over phases of the engineering services plant and equipment. This
assessment will be based upon first hand experience of the time actually taken to
commission and test major projects.

The time allocated will take account of such matters as:

      The “re-work” necessary on many projects to re-test plant and equipment that
       has been either under/over-sized or has been subject to repair.

      Delays due to the inability to sequentially commission and test plant in an
       ideally logical sequence because of unforeseen events such as a temporary
       lack of labour resource and/or disruptive building activities.




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      The common failure on the part of Building Construction Planners to integrate
       the construction of the building with the quite different priorities of the
       engineering services e.g. floors tend to be completed on a horizontal basis
       whereas many engineering services are vertically distributed and balanced.

On projects where a Commissioning Manager is not involved or the Commissioning
Manager is engaged at too late a stage in the project, idealistic timescales for the
Commissioning and Testing process, with no float incorporated, tend to be built into
the overall construction programme by Building Construction Planners.

Conversely, realistic timescales allocated by Commissioning Managers for the
Commissioning and Testing process can be up to twice as long as the ideal assumed
by Building Construction Planners. For a commercial air-conditioned office
development of say 100,000 sq ft net lettable area, 6-9 months for the
Commissioning and Testing works is not an unrealistic time span. A common initial
reaction from Construction Project Managers to this suggested timescale is to
assume that the project will be delayed if this time period is built into the overall
construction programme. However, this does not need to be the case for the
following reasons:

      If a sensible amount of float is built into every Commissioning and Testing
       activity, when unforeseen circumstances do arise, there should be time
       available to adopt alternative strategies to mitigate any potential delay.

      Projecting the “realistic” timescale for the Commissioning and Testing
       activities back from the contract completion date will highlight the potential
       impact of the Commissioning and Testing works on the construction process
       and can be planned for in good time. This may well necessitate some re-
       planning of the construction works themselves.

      Drawdown on skilled labour resources can be more easily accommodated
       over a longer period of time.




Activity Stacking

The above initial time allocation for the overall Commissioning and Testing process
as inputted by the Commissioning Manager, will probably not be based upon a
detailed logic/precedence diagram. This is because this detailed planning has to be
undertaken at a later stage by the Main Contractor in conjunction with his relevant
M&E Sub-Contractors and Specialist Suppliers once they are appointed.

Although the production of a detailed logic/precedence diagram by the Main
Contractor is often a contractual requirement, it has been the writer’s experience that
unless a Commissioning Manager is engaged to assist in the process, such diagrams
are rarely produced in a timely fashion i.e. soon after the appointment of the relevant
Sub-Contractors.

This failure can be attributed to several factors including the absence within the Main
Contractor’s organisation of the necessary expertise in the Commissioning and
Testing process to produce such diagrams.




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This lack of expertise can extend to the Commissioning Specialist employed by the
M&E Services Sub-Contractor, because such specialists tend to be engaged for the
“hands-on” activities of air and water balancing only.

Let us continue for the moment on the assumption that on a particular project it has
been decided to not have a Commissioning Manager in order to “save cost”. The
Client’s Project Manager, in the absence of any expert advice to the contrary and
lacking the detailed knowledge of the Commissioning and Testing process, may well
accept the Main Contractor’s assurances that such logic diagrams are not necessary
at all.

Even in cases where the Project Manager does enforce the contractual requirement
to produce a detailed logic diagram, by the time the Main Contractor has been
coerced into producing one, often it is too late into the overall
installation/Commissioning and Testing process for the programme to be meaningful
i.e. any float that may have existed is no longer available. Contractual constraints on
the Main Contractor usually result therefore in the activities on the logic diagram and
associated Gantt chart being “stacked” vertically in order to retain the original
contract completion date.

The features of such “stacked” programmes are as follows:

      If a drop-line is superimposed over the most intense period of activity, it
       emerges that an impossibly high number of technicians are needed to
       complete the programmed activities.

      An ideal sequence of parallel and sequential activities emerges with no float
       available to mitigate potential delay from the inevitable unforeseen technical
       problems arising.

      Because the Commissioning and Testing activities are indicated starting so
       late in the overall construction process, the Main Contractor can create the
       false impression that he is “on programme” for the majority of the construction
       period time allocation. However, within a couple of weeks of trying to carry
       out the multitude of simultaneous activities indicated on the stacked
       programme, it becomes apparent that it was an impossible task that has
       created a virtually irrecoverable situation.

In the meantime, the Project Manager, having been providing the Client with the
assurances that, although the programme may have been “tight”, the Main
Contractor was still on programme, is suddenly reporting serious delays. By this
time, the entire Professional Team’s capabilities to manage the overall construction
process are being brought into question by the Client.

Engaging a Commissioning Manager at the outset of a project can help to prevent
this situation developing.




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                EXAMPLE OF ACTIVITY STACKING



           ACTIVITY                                  TIME



 COMMISSION CONTROLS


 COMMISSION AHU’S


 WATER BALANCE LTHW


 COMMISSION BOILERS
                                                                           HIGH LEVEL OF
                                                                           RESOURCING
 WATER BALANCE CHILLED
 WATER

 COMMISSION CHILLER


            ON PROGRAMME                                      POTENTIAL FOR DELAY




With the Client’s authority behind him, the Commissioning Manager will be in a
position to “burst the bubble of blind optimism” that is often exhibited by Main
Contractors. He can use his experience of the Commissioning and Testing
processes to make a significant contribution to the planning of the overall
construction and Commissioning and Testing works.

The fear is occasionally expressed by Project Managers that, by providing such
advice, the Client’s Commissioning Manager is in danger of becoming wrongly
involved contractually in the construction decision-making process. It has to be
stressed that any “advice” offered to Main Contractors by the Commissioning
Manager is precisely that i.e. either it is taken on board by the Main Contractor or he
can choose to ignore it. In any event, the Main Contractor will be underwriting the
resultant programme, not the Commissioning Manager.


Fire Alarm Cause and Effect Diagrams/Schedules

Further into the construction and subsequent Commissioning and Testing processes,
the need often arises on commercial developments to produce for the fire alarm
system what has become known as a “Cause and Effect” diagram/schedule.




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           FIRE ALARM CAUSE AND EFFECT DIAGRAM




                                                                                EFFECT




                                                                                                  FULL EVACUATION
                                                            EVACUATE 4TH, 6TH
                                                            AND 7TH FLOORS



                                                                                  GROUND FLOOR
                                                                                  PARK LIFTS AT
              CAUSE

     ST             TH
 1        KNOCK 5        FLOOR

     nd             TH
 2        KNOCK 5        FLOOR




These diagrams/schedules can describe in both written English but more commonly
a matrix format, the inter-reaction between a fire alarm activation i.e. a “cause” and
the end result or “effect”. For example, in the event of a smoke detector being
activated, two floors above the affected floor and one floor below may be evacuated
as a safety precaution until such times as the fire has been investigated. Once a
second detector has been actuated within an agreed time limit, the building may well
be placed into full evacuation mode.

The matrix that would indicate this “Cause and Effect” has to be drawn up by either
the M&E Services Contractor and/or the fire alarm specialist supplier. The matrix
would be derived from the fire philosophy specification drawn up by the M & E
Services Consultant. The production of this document by the M&E Services
Contractor can prove elusive but this again is where the Independent Commissioning
Manager can help in co-ordinating this exercise.




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Block Wiring Diagrams

The cause and effect matrix itself should be based upon ideally, a block wiring
diagram indicating the inter-connecting wiring between, for example, the fire alarm
panel and the lift control panel, possibly via an interface unit.



                            BLOCK WIRING DIAGRAM


                  3-Core Cable Installed by Fire Alarm Supplier




           1     2    3                                        12    13    14


    Cables Terminated by                                Cables Terminated by
        Lift Supplier                                    Fire Alarm Supplier

               LIFT PANEL                                  FIRE ALARM PANEL




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This inter-connection would ensure that in the event of a fire, the passenger lifts
would park at the ground floor with their doors open. The production of such a block-
wiring diagram can again prove to be problematic. This is because responsibility has
not been allocated for the installation of inter-connecting wiring and the actual making
off of cables in particular panels.

The Commissioning Manager can help this process by co-ordinating the overall
production of the block wiring diagrams and helping to establish where the
responsibility for both cable installation and cable terminations lies.

The resultant AO size drawing that emerges from this exercise can be marked up
with panel reference labels, cable types, which party is responsible for installing them
plus responsibility for the making off of cables into which terminals. These are all
activities and responsibilities that, in theory at least, should have clear lines of
demarcation. In reality, it is not an uncommon occurrence for Engineering Services
Consultants, Main Contractors, Services Sub-Contractors and Specialist Suppliers to
find little agreement amongst them about who should be producing such information.

Yet again, the Independent Commissioning Manager can mediate a way through this
situation because each of the affected parties is often willing to accept the
Commissioning Manager as an “honest broker” in such situations.

The great advantage of this approach is that under the “chairmanship” of the
Commissioning Manager, all of the parties involved are brought together to discuss
and thoroughly understand the overall fire strategy. They are obliged also to
establish their precise areas of responsibility.


Commissioning of Major Plant

The Commissioning and Testing of major plant and equipment such as water chillers
is another process that is rarely provided with the high level of co-ordination that it
requires. For example, the activities required to successfully commission a water-
cooled chiller can include:

               Provision of correctly regulated and balanced water supplies to
                cooling towers, condensers and evaporators.
               Provision of safe electrical power supplies and control systems.
               Provision of a false load, possibly via the use of pumps, air handling
                plant, boilers and associated heating systems.
               The full Commissioning and Testing of the cooling towers
                themselves including water treatment, air circulation fans and
                associated starters.

All of the above activities need to have been completed prior to the arrival on site of
the chiller Specialist Commissioning Engineer.
In all too many instances, he arrives on site only to discover that one of the above
critical activities has not been carried out. Many hours are then wasted while he
“muddles his way through” a less than perfect day making temporary provisions for
any lacking facilities. In a “worst case scenario”, he would be obliged to return to his
depot without achieving anything.

Arranging a return visit to site for Specialist Engineers can result in delays of weeks
rather than days because of the great demands placed upon such skilled operatives.



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The Commissioning Manager in his management role can ensure that all of the
above activities have been integrated into a critical path analysis programme and
have been completed. In this way, any potential problems arising will have been
mitigated by the appropriate inclusion in the programme of suitable “float” for each
activity.


Conclusions

It is apparent from the above observations and recommendations that timely and
effective Commissioning Management activity can:

      Eliminate many of the traditional difficulties experienced during practical
       commissioning, by anticipating and mitigating potential delays to the
       Commissioning and Testing programme.

      Deliver on time to the Client fully functional building services, thereby
       supporting the business function at least cost.

      Assist compliance with the statutory requirements of Part L of The Building
       Regulations.


Summary

It is apparent from the examples given within this paper that the Commissioning
Manager has a vital role to play in the planning and co-ordination of the
Commissioning and Testing activities associated with major construction projects.
Useful feed-back and also of ways in which the management process can be
improved, have been provided within this paper. It cannot be over emphasised
however, that the planning of these activities is of crucial importance, be it in the form
of critical path analysis and/or precedence diagrams.


Richard Wilkins
C Eng, FCIBSE, MInstR
Associate EC Harris




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