Article Safety

Construction Design & Management Regulations 2015 – implementation

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Tags: AGS CDM 2015 construction Equipe HSE RPA Safety Services

Article written by Tom Phillips, RPA Safety Services and Julian Lovell, Chair of AGS Safety Working Group and Managing Director of Equipe.

CDM2015 came into effect on the 6th of April 2015 and duty holders within the geotechnical sector are starting to grapple with the reality of implementation. With an increased emphasis on Client responsibilities, in an industry sector where the Client is rarely directly involved in the ground investigation phase, questions about how the regulations will be applied are being asked.

In conversation with the Health and Safety Executive, Tom Phillips of RPA Safety Services and Julian Lovell, Managing Director of Equipe and Chair of the AGS Safety Working Group attempt to clarify some of the questions consultants and contractors are raising.

Q. The definition of ‘construction’ in regulation 1, excludes site survey and in many cases our clients see ground investigation as site survey. Could you clarify the limits of site survey?

Site survey is restricted to non-intrusive works so taking levels, making measurements, site walkovers, gas monitoring and visually examining structures for faults would all be typical examples. If the works involve penetrative works, even with hand tools, the work is classed as construction and the regulations apply.

We are keen to stress though, that the regulations should be applied proportionally to the level of risk involved. A shallow, hand dug trial hole will require minimal paperwork in terms of a construction phase plan, as the risk is low, but duty holders will still need to consider the risks associated with such things as underground services, contaminants, ground stability, preventing falls into the excavation and they must plan how the work will be carried out, kept safe and made good. In many cases, simple repetitive work will be based on standard company procedures but these will need tailoring for the site and locality in question and the prevailing conditions.

Q. Consultants and contractors are finding it difficult to get clients to accept and fulfil their duties under regulation 15 (1), which states: ‘A contractor must not carry out construction work in relation to a project unless satisfied that the client is aware of the duties owed by the client under these Regulations.’ In many cases they are not employed directly by the client and have no contact with them at all.

To what extent does this prevent contractors from starting work and will they be held liable for client’s failures to make the correct appointments and satisfy their duties?

The regulations do not prevent geotechnical contractors working, even if the client has not fully complied with their duties. Key for the contractor, is to ensure they have made the client aware of the client’s duties under CDM. This can be done as part of the tendering process, or following appointment.

In such instances, the contractor still needs to make wider arrangements to manage the site for the duration of their attendance (appropriate to the role they are carrying out) despite a lack of formal appointment.

The contractor should therefore ensure the site is secure, ensure suitable welfare arrangements are in place and comply fully with their part 4 duties under the regulations. They should also prepare (or contribute to an existing) Construction Phase Plan which will deal with how they intend to arrange the work and how they will manage foreseeable hazards both at and adjacent to the site.

The construction phase plan should also identify any additional information that the contractor needs before starting work. If the client is not able to provide that information (e.g. services location, intrusive asbestos survey, ordnance assessment, etc.) then the contractor should arrange with the client for the work to be carried out as a separate part of the contractor’s contract.

Where the contractor is the main contractor on all or part of the site they should manage all work in the area they are responsible for unless a principal contractor is appointed and active. Where the contractor carries out design work (e.g. temporary works including perimeter fencing, arranging traffic management routes, ground conditions assessment and alterations, excavation support arrangements, etc.) they should ensure they follow the principle of avoid the hazard or use a suitable control measure to minimise risk.

Q. When a geotechnical contractor is appointed as Principal Contractor (PC) or Principal Designer (PD), in the early stages of a GI phase, or they pick up those duties by default, is there a danger they could be deemed PC and PD for subsequent phases?

Absolutely. Without clear arrangements to the contrary, there is every danger that a geotechnical contractor could be assumed to be responsible for following phases of works. It is therefore important that where a geotechnical contractor is appointed, or by default is expected to carry out the duties of the Principal Contractor and Principal Designer (a requirement on any project where there is likely to be more than one contractor), they clearly limit their role to their phase of works only. This will include limiting the Construction Phase Plan to the geotechnical phase. Where the existing contract paperwork is not clear on this issue the contractor should write to their client to confirm the extent of the contractor’s role.

Q. Regulation 2 defines a contractor as ‘any person (including a non-domestic client) who, in the course or furtherance of a business, carries out, manages or controls construction work’. Does this definition mean consultants may be classed as contractors?

The duty holder ‘contractor’ relates to those who: determine the manner in which the work is being done (this may also include a design element so they may hold dual roles), provide supervision or engage other contractors. This can include ‘consultancies’ in many instances.

As an example, where a consultant engages a drilling contractor and determines the nature and type of works or supplies supervision, they would both be deemed contractors and it will be the consultancy’s responsibility to ensure the client is aware of their duties. The client would then need to make the necessary appointments. Where a domestic client is involved, the consultancy (as a contractor) may be deemed to be principal contractor and principal designer by default, even if the client fails to make formal appointments. Where a commercial client is involved, any failure to appoint will result in the client carrying the role of principal designer and/or principal contractor.

Further reading:

HSE Publication L153 – Managing health and safety in construction – Construction (Design and Management) Regulations 2015 – http://www.hse.gov.uk/pubns/books/l153.htm

CITB Guidance on CDM – http://www.citb.co.uk/health-safety-and-other-topics/health-safety/construction-design-and-management-regulations/cdm-guidance-documents/

Article Contaminated Land Laboratories

Asbestos in Soil

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Tags: airborne Asbestos caution Guidance HSE

The AGS is active in establishing industry guidance for asbestos in soils. The CLWG and LPWG have formed a small sub-group to discuss what guidance and advice should be provided for our Members, and to contribute to the work that is currently being undertaken by other groups and associations on this issue. This article is intended to give Members an awareness of the present situation; what has happened, what is being done and what may be happening in the future.  It has been suggested that many of our members, while insured for investigating and providing advice on contaminants, have specific exclusions to their professional indemnity policies in regard to claims relating to asbestos, and this may possibly have indirectly led to a lack of training and awareness about the risks of asbestos in soils.

LEGAL ASPECTS
Attempts by government agencies and independent organisations to define “safe” or “minimal risk” threshold concentration values, either for fibres in soil or for fibres in air, have been thwarted by the scientific evidence that death can be caused by a single fibre.

The current legal rule in relation to Mesothelioma is that any “material increase in risk” is sufficient for legal liability. In a recent appeal court ruling the exposure was judged to be just 18% higher than background levels.

REGULATIONS
The UK, in 1931, was the first country to establish laws regulating exposure to asbestos, primarily to protect the health of factory workers.

Currenty UK Statute is dominated by the Control of Asbestos Regulations (CAR) 2006 which were implemented under the provisions of the 1974 Heath and Safety at Work Act and bring together the three previous sets of Regulations covering the prohibition of asbestos, the control of asbestos at work and asbestos licensing.  However, while these regulations are relevant for asbestos in soil, they do not define limits or best practice and there is currently no specific published guidance from either the HSE or the Environment Agency.

TRAINING
The British Occupational Hygiene Society (BOHS)  have a series of asbestos-related proficiency qualifications that cover the identification, sampling and management of Asbestos in Buildings.
The development of specific training and qualifications for the contaminated land industry is being actively considered by various bodies and will need to include consideration of the following issues

  • background of asbestos; including health effects
  • recognition of debris in soil that may contain asbestos
  • procedures to be followed when soil that may contain asbestos is identified
  • safe packaging, labelling and handling of soil samples that may contain asbestos
  • the nature of operations that could result in exposure to asbestos
  • proper use, handling and disposal of personal protective equipment (PPE)
  • personnel decontamination
  • equipment cleaning

FIELDWORK and SITE WORK MANAGEMENT
All personnel either organising fieldwork or inspecting and/or handling suspected asbestos-contaminated soil or being exposed to soil-disturbing activities at sites where there is a risk of asbestos-contaminated soil being encountered must be able to demonstrate an appropriate level of awareness of the risks associated with asbestos-contaminated soil.

The first step is to identify the potential for asbestos at a site by studying the site history and to exercise an appropriate level of caution. Asbestos may be expected within the demolition rubble from former buildings, in association with buried heating pipework and ducts, or simply within fly-tipped materials.  Asbestos Containing Materials (ACM) have been in use since 1834 but were most widely used between the 1950’s and the 1980’s.  The use of ACMs was not banned until 1999.

The potential for fibre release from ACM in damp soil may be limited, but if the site is dry and dusty, fibres may readily become airborne.

In addition to artificially damping down dust down drilling or trial pitting activities, the following PPE can be considered:

  • Boots that can be easily washed down.
  • Disposable overalls(type 5) fitted with a hood
  • High efficiency disposable particulate air respirator (FFP3)
  • Disposable Gloves
  • Goggles

Any suspect fibrous material or any cement / board type products which have evidence of fibres within them should be considered to potentially contain asbestos and samples must be taken for subsequent laboratory confirmation. All samples should be double-bagged with both the sample container and outer bag labelled as potentially containing asbestos so that the laboratory can take all the necessary precautions to prevent exposure to their staff.

Asbestos may occur as:

  • Sprayed coatings and wrapped lagging used for thermal & fire protection,
  • Insulating boards, wallboards and ceiling tiles used for fire protection, thermal and acoustic insulation
  • Profiled and flat roofing sheets, partitioning boards and decking tiles
  • Bitumen products, mastic pads, roofing felts gutter linings
  • Ropes and yarns
  • Cloth mats, fire blankets
  • Millboard and paper, general heat insulation
  • Flooring, thermoplastic, PVC floor tiles, mastics, sealants etc
  • Textured coatings e.g. artex
  • Bakelite

LABORATORY ANALYSIS
Unless a formal screening is requested by the person commissioning the laboratory testing, the laboratory will simple carry out a visual check.  There is an issue here in that a large proportion of soil samples are put through laboratories without any formal screening and it has been conjectured that significant percentages of made ground samples are passing through both geotechnical and analytical laboratories with undetected asbestos.

Most labs provide a tiered approach involving screening, identification and quantification:

  • Basic screening: examined under an optical microscope with magnification of x2 to x5
  • Detailed screening: ditto with magnification of x10 to x40
  • Identification: Polarised Light or Phase Contrast Microscopy (PLM or PCOM)
  • Quantification: Gravimetric (typical LoD 0.1%) *
  • Quantification:  Sedimentation and Fibre Counting (typical LoD 0.001%)

*The Gravimetric quantification method is currently being phased out.
EXISTING GUIDANCE
Current UK workplace regulations for asbestos in air have a single Control Limit (max. concentration of fibres in the air averaged over a 4 hr period) for all types of asbestos of 0.1 fibres per cm3 (100 000 f/m3).  The World Health Organisation indicate that 1000 f/m3 is associated with a 10-6 to 10-5 risk of lung cancer in a population where 30% are smokers and 10-5 to 10-4 risk of Mesothelioma.

ICRCL Guidance Note 64/85 “Asbestos on Contaminated Sites” (1990) is still the most current guidance for asbestos in soil and suggest asbestos fibres should be  <0.001% w/w.

Waste Soil containing >0.1% w/w asbestos is classified as hazardous waste.

The key issue in assessing risks from asbestos in soil relates to modelling the exposure. It is not possible to use the CLEA model to calculate exposure and no reliable quantitative relationships between factors which affect asbestos fibre concentration in air and asbestos concentrations in soil are known.

There is some consensus between the UK (ICRCL), Dutch and Australian Guidance on the use of a threshold of 0.001% as a threshold for asbestos in soil. The Dutch Guidelines consider the risk from Chrysotile to be ten times less than Amphibole asbestos but the HSE, WHO, the Australian DoH and the USEPA have chosen not to distinguish between different asbestos fibre types.

For bound asbestos there is recognition that the potential generation of asbestos fibres is much lower and hence Dutch and Australian guidance use a threshold ten times higher than that for friable asbestos.

The USEPA use a method based on direct measurement during vigorous activity to assess the soil by measuring ambient air concentrations. A measurement approach is also used in the Dutch guidance.

New Guidance
It is believed that the Environment Agency and the HSE have in recent years collaborated to prepare new draft guidance for asbestos in soils in the form of a document entitled ‘A Study to Derive Soil Guideline Values for Asbestos in Soil’.

It was rumoured that this draft guidance recommended use of a strategy based on the Dutch approach for the assessment of soil contamination with asbestos.  However, the EA have seemed reluctant to publish this document, and despite a recent Freedom of Information request by the EIC it is now not expected to emerge, being instead superceded by a forthcoming update to the HSE document HSG248 (2005) ‘Asbestos: The analysts’ guide for sampling, analysis and clearance procedures’. Public consultation on this HSE document is awaited.

 

THE FUTURE
The AGS are supporting a current EIC incentive to develop best practice industry guidance with input from the EA / HSE / HSL/ BOHS and CL:Aire.  A CIRIA project has also been launched with similar goals so we may at present end up with two (or more!) pieces of industry guidance.     For the immediate future there is planned to be a workshop organised by CL:Aire in association with EIC & BOHS  at the Manchester Conference centre on the 1st November 2011.

Article Safety

Be On Your Guard

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Tags: Geotechnical HSE rigs

During recent years our industry has made great progress in providing rig guarding for piling and drilling rigs. Responding to the well publicised campaign from the HSE, it is now the case that we can expect that the rigs that are deployed for applications from well-drilling and SI through to heavy foundation work will be guarded. Specifically, this means that fixed or interlocked guards are normally practicable extending from 0.5m to 2m above ground level.

Of course, this is designed to protect the workforce and anyone who passes nearby to a rotating auger or drill string; and rightly so. But the responsibility does not rest entirely with the contractors.

To quote the CDM regulations, “Every designer shall in preparing or modifying a design…avoid foreseeable risks to the health and safety of any person carrying out construction work”.

But how does this apply to rig guarding, something which must seem esoteric when designing a piled basement or grouting project or even a site investigation?

It is HSE guidance that if the piling or drilling equipment cannot be operated with sufficient guarding then it is likely that the designer has not adequately considered the health and safety of those constructing the works. In other words the designer has failed to allow adequate working space for the piling rig to be operated safely.

This places a wide responsibility on our geotechnical professionals. Given the huge range and constantly changing equipment that is available to contractors, this obligation is hard to meet without specialist advice.

Frequently there is no single answer to a particular set and combination of conditions. Furthermore the industry continues to innovate. Contractors are now able to offer “wing-guards” that permit working very close to a wall or obstruction. Solutions can be found to safely drill or pile in corners and even electronic guarding is available on some machines, obviating the need for physical barriers altogether. Whilst this is of benefit to the project, it is essential that the designer considers all of this at design stage.

Given the progress that is being made designers (and for that matter CDM Co-ordinators) need to involve the specialist supply chain at an early stage. Advice should be sought and then taken into account in the design of the works. These discussions are likely to take place months if not years before actual construction takes place. For this and other reasons any specialist input should be recorded, preferably in writing and it should certainly form part of the CDM risk assessment.

Professionals need to be diligent and careful in identifying the risks associated with geotechnical work. By seeking advice from specialists, up-to-date techniques and methods can be incorporated into the safe execution of the project and into the relevant risk assessments. Only by doing so can we ensure that the protection offered by physical guarding extends to us all.

Article Safety

Unexploded Ordnance – a Construction Industry Guide

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Tags: construction HSE Unexploded Ordnance

As the representative of the AGS on the project steering group for the forthcoming CIRIA construction industry guidance on UXO, Andy O’Dea of Peter Brett Associates LLP updates us on the scope of the guidance and the benefits it will bring.

In the March 2005 issue (number 49) of the AGS Newsletter, you published a letter from my colleague at Peter Brett Associates LLP (PBA), Richard Thomas, on the controversial issue of unexploded wartime bombs (UXBs).  It transpires that this was one of the contributing factors to CIRIA commissioning a research project to produce definitive guidance on the issue for the construction industry.  PBA has part funded the project and I have been involved throughout, representing both the AGS and PBA on the project steering group.  The final report is nearing completion and is likely to be published in the coming months.  I thought it was timely for me to write to update the AGS on the scope of the report and the benefits it will bring.

The assessment of risk associated with Unexploded Ordnance (UXO) is controversial and fraught with difficulties.  For example, several thousand items of ordnance are removed from construction sites in the UK each year (of which some 5% are live).  However, in the period 2006/2007 (readily available HSE records), no reported injuries to construction workers were attributed to incidents involving UXO.  This is in spite of other risks or accidents in the UK construction industry resulting in 77 fatalities, 3,711 major injuries and 7,108 other reportable injuries. Make no mistake about it, the risk associated with UXO is overwhelmingly influenced by the consequences of an event rather than the likelihood of encountering or detonating a device in the first instance.

Three main issues drove PBA to get involved in the project:

  1. A lack of any consistency in the assessment and reporting of UXO risk across the industry.
  2. An absence of scientific or methodical processes in the ‘black art’ of UXO threat assessment.
  3. The perceived conflict of interest in a UXO specialist providing advice on required mitigation measures and then offering contractor services to mitigate the risk.

 

We are pleased to say that all three issues have been addressed by the project guidance.

We feel that the report is a comprehensive and extremely useful piece of work that will help to dispel many of the myths surrounding UXO and allow future UXO risk assessments to be supported by a consistent and rigorous approach that is underpinned by scientific reasoning.  The report provides a comprehensive introduction to UXO and outlines the duties and responsibilities of the parties to a construction project in the context of UXO risk.  A clear and concise flow diagram outlines the risk management framework; from preliminary risk assessment (that can be carried out by a non-UXO specialist) through to detailed risk assessment, where required, (to be conducted only by a UXO specialist) and on to risk mitigation and implementation.  Each element of the risk management framework is described in full detail in subsequent chapters of the report.  Advice on emergency response planning and the appointment of UXO specialists is drawn out in the later chapters.

The report is supported by a dozen or so relevant case studies and especially important issues are emphasised in highlighted boxes.  Example risk assessment reports, verification reports and clearance certificates are provided in the appendices along with the ‘nuts and bolts’ of UXO survey techniques, equipment and limitations.

The report has been through a rigorous consultation process and has been distributed widely across the industry for comment on a number of occasions.  Consultation responses have been received from developer clients, regulators, consultants, contractors, infrastructure bodies, government defence organisations, academia and professional bodies such as AGS.  A special note of thanks goes to those at the AGS who have given their time and expertise in reviewing the report and making the consultation process a success.

This report presents a major advance in helping to provide a consistent and robust approach to the assessment of UXO risk in the construction industry and is to be welcomed.  Undoubtedly, it is a first step and further guidance will follow in time.  However, CIRIA Report RP732 Unexploded Ordnance (UXO) – a construction industry guide, is a big step in the right direction.

Andy O’Dea
Senior Associate
Peter Brett Associates LLP
17 September 2008

Article Business Practice Data Management Executive Safety

Establishing Ground Rules

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Tags: construction ground HSE Investigations

Concerns over the place of Ground investigations in relation to CDM led John Banks and Mouchel Parkman to raise queries with HSE and an APS Legal Adviser. We print below the critical exchanges for the benefit of all those who may encounter similar concerns/ problems.

From John Bans (Technical Director of Mouchel Parkman and Finance Director of APSt) to staff at Mouchel Parkman

“I have attached a copy of the legal advice received from The Association for Project Safety relating to the application of CDM Regulations to Ground Investigations. The reason for asking for a specific ruling was the attitude of the Contractor who despite being informed (via structure and correct ICE Conditions of Contract) that we expected them to be Principal Contractor, moaned about the fact once appointed.  The work is small in scale: 3 days trail pitting, then a break and then returning to undertake the boreholes for 3 weeks.

You will note that the ruling supplied states that it is the project that is important (building schools [and in fact most projects] generally takes longer than 6 weeks to construct)

I know I have started this before but note that:

  • All Ground Investigations, allied to a larger project will have a construction period of no longer than 6 weeks (and generally that is the only reason we are doing them), need a CDM Co-ordinator and Principal Contractor

The only exception is where we are undertaking Ground Investigations and there is no final project (seeing if a site is within Part 11A, etc)”

 

The APS Legal Advisors had responded to John’s enquiries as follows:
“The issue in this query centres around the definition of a project. This is defined in regulation 2 as “a project which includes or is intended to include construction work and includes all planning, design, management or other involved in a project until the end of the construction phase”.

The ground investigation is part of a larger project. The definition of a project extends to include the planning and design, which is taking place at the same time as the ground investigation. It would be artificial to treat the ground investigation works as separate from the project as a whole.

The difference between treating the ground investigation as part of a notifiable project, and treating it as a stand alone project which is not notifiable, need not be very great.  The ground investigation contractor would of course have the duties of a principal contractor, but contractors have duties under CDM2007 in any event if their work is not notifiable (see regulation 13).

Because of the limited nature of the works, the health and safety file would not need to be lengthy or elaborate. The health and safety plan would deal with the specific risks only. Similarly the health and safety file would not need to cover more than the residual risks arising out of the ground investigation works or which have become apparent as the result of those works.”

The Mouchel Parkman Compliance manager had also sought the views of the HSE at Rose Court via infoline and received the following.

“You are correct in every respect. The ground investigation works are part of the notifiable part of the project. It is not unusual for ground investigation works to take place early, perhaps long before the appointment of the Principal Contractor who will be undertaking the management of the main construction phase. However, it is still part of the same overall project.

As the project is notifiable, and the ground investigation is part of the notifiable project, there needs to be a Principal Contractor (PC) appointed. If the only work being carried out on site is the ground investigation, then I do not understand why the ground contractor thinks they are not competent to act as PC- for themselves. The role of PC is essentially to co-ordinate the construction work on site, to ensure that it is carried out safely. I assume the contractor feels confident enough to do their own work safely.  There will be a requirement to fence off the site, liaise and co-ordinate with the school/client to ensure safety to children, staff and the nearby public, and ensure welfare facilities. Their construction phase plan will only need to go as far as covering their involvement at the site. At the end of their work, presumable they relinquish the role of PC, which is subsequently taken up by the PC for the main construction phase plan.

If there will be other contractors working at the same time as the ground investigation contractor, I can understand their reluctance if they have not been in a position to manage other contractors before, and they may not have personnel capable or competent to do this task. Otherwise, acting as PC for their own work only, should not create any extra demands.

Ref: Article taken from APS newsletter/ October 2007

Article Safety

Drilling down into industry safety

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Tags: HSE risk assessment

Site investigation companies should expect increased HSE attention following the recent successful prosecution of CET Limited following an accident where a drill rig operator was forced several times through a 24cm gap between the mast and the auger. Guarding and stopping devices were considered inadequate and not in compliance with the Provision and Use of Work Equipment Regulations 1998 (PUWER).  CET were fined £20,000 (plus costs of £30,000) under Section 2 of the Health & Safety at Work etc Act 1974.

A second, recent, incident, were the operator suffered a broken shoulder and two broken arms in similar circumstances only serves to underline the seriousness of ignoring the PUWER requirements.

Many AGS Members will already have received a letter from the HSE clarifying the legal responsibilities of employers to safe guard their employees.

Legal Requirements

Under current UK legislation employers’ legal duties include the following:

  • To ensure, so far as is reasonably practicable, the health & safety of their employees.
  • To undertake a suitable & sufficient assessment of the risks to health & safety to which their employees, as well as other people, are exposed arising from their undertaking or work.  The significant outcomes of the assessment will normally have to be recorded.
  • To provide effective measures to prevent access to any dangerous part of machinery.
  • To ensure that, where appropriate, work equipment is fitted with one or more readily accessible controls to bring the machine to a complete stop where necessary for health & safety reasons (an emergency stop).
  • To ensure that, apart from where necessary, no control for work equipment is positioned where it would cause a risk to the health & safety of the operator.

Common Failures

Recent investigation by HSE has shown that people may be being placed at risk due to one or more of the following reasons:

  • A risk assessment has not been done & acted upon.
  • A risk assessment has been done but is neither suitable & sufficient in that it does not correctly identify the measures that could reasonably be taken to eliminate or reduce the risks identified.
  • Access to the dangerous rotating parts of the drilling machinery is not effectively prevented in line with the hierarchy of protective measures given in the Provision & Use of Work Equipment Regulations 1998 (PUWER) & backed up in the BDA guidance.
  • Insufficient or inadequate emergency stops are provided.
  • The operator position places them in close proximity to the rotating part of machinery.
  • The nature of the work undertaken requires close approach to a rotating part of machinery.
  • Operators are not adequately trained or supervised.

Risk Assessment

The purpose of a risk assessment is for an employer to identify the risks his employees, & others affected by his work, may be exposed to.  Once this is done the employer should identify the measures that need to be taken to deal with these risks.

The primary aim should always be to completely eliminate any risk identified e.g. by effective guarding; where this is not practicable the risk must be reduced as much as possible by safe systems of work & the provision of information, instruction & training.

HSE has found that drilling equipment frequently requires close approach to the rotating drill string whether to operate controls, to take samples, backfill or for other reasons.  This obviously increases the risk of people becoming entangled if access to the dangerous part of machinery is not effectively prevented.  Any risk assessment needs to recognise the implications of this risk & ensure that the protective measures chosen offer the highest practicable level of protection.  Large piling rigs are covered by separate guidance produced by the Federation of Piling Specialists in liaison with HSE taking into account the different nature of the risks.

Levels of Protection

PUWER lays out a clear hierarchy of protective measures that is further clarified with direct reference to the drilling industry in the BDA guidance*.  In simple terms the hierarchy for preventing access to the rotating parts of a drilling rig is as follows:

  • A fixed guard that requires physically unbolting.
  • A moveable guard with an interlock cutting rotational power when opened.
  • An adjustable guard (i.e. a fixed or moveable guard with adjustable parts or whole), the adjustable part must be interlocked. These are commonly described as “telescopic”.
  • A caged working area that is interlocked thus preventing risk from rotation when anyone is in the area.
  • Trip wires or bars.
  • Proximity sensors or light beams.
  • Training & supervision.
  • Appropriate clothing with no loose attachments.

The last two points are not “stand-alone” measures but should be provided in all cases.  

Where access to the rotating drill string is to be prevented by a guard it should extend from 0.5 metres above ground level in all cases to 2 metres above ground level or 2 metres above the operator position if elevated.  The rotating drill string, even at relatively low speeds, is an extremely dangerous part of machinery.  The law demands that the highest practicable level of protection should be supplied to prevent access to the dangerous part.  As the BDA guidance quite correctly states in the “protective devices selection” section the actual decision must be made impartially & with safety, not time or cost, as the overriding concern.

In HSE’s opinion, given the practical operational difficulties a fully fixed guard would give, the best practicable solution in the majority of cases will be some form of moveable, interlocked guard.

It should be remembered that the rotating drill string is always to be considered a dangerous part of machinery from which people require the highest practicable means of protection.  This will not always be the most convenient or cheapest option available.

Where manufacturers are no longer trading, or effective guards are not yet available, bespoke guarding options can be retrofitted easily in most cases.

Trip Wires, Stop Bars & Light Beams

Trip wires & stop bars are included in the hierarchy but they are clearly a lower level of protection than a physical guard be it interlocked or fixed.  In order to activate a trip wire or stop bar the person is usually already entangled given the proximity of the device to the drill; plus due to the “wind-down” time further injury is likely once the device is activated.

PUWER requires access to be prevented – trip wire, stop bar or light beam type fixtures positioned in close proximity to the drill string will not usually prevent access to it.  They may reduce the level of injury once a person is entangled but they do not prevent the accident occurring.

Only where a physical guard which effectively prevented access was evidently impracticable would HSE consider a trip wire, light beam, pressure pad or stop bar arrangement a realistic option; further additional measures may also be needed to lower the risk to an acceptable level, for example, relocating operator positions, the fitting of devices to remove spoil automatically preventing repeated activation, a strict regime of maintenance & testing & close supervision.

Emergency Stops

At least one emergency stop should be fitted to each rig, one being next to the operator position.  Such stops must be separate from the usual off switch & require manual re-set so that they cannot fail to danger once activated.  They should be so designed as to bring the part of the operation causing the danger to a complete halt in the shortest achievable amount of time.

Other Considerations

Whilst the risk of injury arising from entanglement is a major risk in operating drilling rigs it is not the only area of concern for the industry.

Risk assessments should also address other associated risks to safety & health.  For example, risks from overhead power lines, underground services, vehicle movements, noise, falling objects, manual handling, soil contamination, the availability of proper welfare facilities to name but a few.

Conclusion

The entanglement risks faced by those operating, or working in close proximity to, drilling rigs are well known.  The legal requirements to protect people are similarly well known & the guidance clear.

The key factor in protecting people from these dangerous machines is a realistically robust risk assessment & the provision of a truly effective means of preventing access to the dangerous part.

HSE will expect to see the highest practicable level of protection in place with full justification for measures from further down the hierarchy where they are found.

We hope that the above guidance is clear enough to leave you in no doubt about the level of protection required.  If HSE has to investigate any further accidents of this kind we will take into account the additional guidance in this annex & letter we have provided to you/your Company in deciding what enforcement action may be appropriate.

============================

 

*  “Guidance Notes for the Protection of Persons from Rotating Parts & Ejected or Falling Material Involved in the Drilling Process” can be supplied by the. British Drilling Association (BDA)  Tel: 01327 264 62

Article Safety

Hand Arm Vibration

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Tags: debonding hand arm vibration HSE piles

HSE are becoming seriously concerned about hand arm vibration while breaking down piles. Members of the Federation of Piling Specialists have experienced difficulties with HSE Inspectors in some regions even when the client has been offered, and refused, the use of a debonding system.

The FPS will be preparing guidance about breaking down piles for publication on their website, and are about to publish the following information on the use of debonding systems:- ” Reinforcement debonding, or any other items attached to the pile reinforcement, can only be placed in the pile to the same tolerances as the pile reinforcement. These tolerances are given in the ICE Specification for Piling and Embedded Retaining Walls 1996. Engineers/Specifiers should therefore specify the same tolerances for pile cut-off-level if such systems are to be used.

·         Before specifying reinforcement debonding, or any other related systems, discussions must take place with the piling contractor in order to investigate the practicality of the proposed system for the chosen piling technique, pile size, the prevailing ground conditions. This technique is not universally applicable.

·         Any system installed should be protected from damage, otherwise the system may lose all intended benefits. For example, the debonding of bars will not be effective if the bars are bent during or after installation.

·         The lifting point for the removal of the concrete over the debonded length should be designed and specified by the main contractor following discussions with the piling contractor.

 Consultants should be aware of their responsibilities under CDM and advise clients accordingly.