C July 2007

Front 1

(a) Define the term ‘confined space’ within the context of the Confined Spaces Regulations 1997.

Back 1

Confined space means any place, including any chamber, tank, vat, silo, pit, trench, pipe, sewer, flue, well or other similar space in which, by virtue of its enclosed nature, there arises a reasonably foreseeable specified risk such as lack of oxygen or the possibility of drowning in free-flowing solids

Front 2

(b) Outline the factors that should be considered to ensure that emergency rescue arrangements for confined space work are suitable and sufficient.

Back 2

*Carrying out dynamic risk assessments;
*Method of raising the alarm to advise those outside to initiate rescue procedures
*Rescue operation carried out by trained and competent emergency rescue team together with procedures for summoning the public emergency services if required and providing them with relevant information;
*Provision of means of communication for those inside the chamber with those on the outside;
*Provision of rescue and resuscitation equipment such as lifelines, lifting equipment and breathing apparatus;
*Safeguarding the members of the rescue team from risks to their health and safety by the provision of personal protective equipment, for example overalls, footwear and head protection;
*Precautions to be taken in the event of fire such as the provision of fire extinguishers;
*Identification of plant in the vicinity that may need to be shut down during an emergency rescue;
*Availability of first aid equipment and trained first aid personnel until the arrival of professional medical help;
*Ensure access to the point of entry for carrying out the rescue operation bearing in mind the possible remoteness of the site.

Front 3

A weld repair to a high pressure steam pipeline requires gamma radiography to be performed to assess the quality of the repair:
(a) Outline the principles of gamma radiography.

Back 3

Gamma radiography passes gamma rays through a test object to leave an image on the photographic film on the opposite side. Defects on the test object will show up due to the differences in intensity of the radiation striking the film.

Front 4

(b) Outline the advantages and disadvantages of this form of non-destructive testing.

Back 4

Advantages of gamma radiography are that
*that it may be used on most materials, ferrous and non-ferrous,
*it detects internal defects and produces a permanent record of the test;
*that it has an in-situ capability and no coupling with the surface of the test piece is required; and
*that it does not require a power source.
Disadvantages of gamma radiography are that
*requires full compliance with the requirements of the Ionising Radiation Regulations;
*that the equipment needs a large exclusion zone for in-situ testing and
*access is required to both sides of the test piece whilst alternatively for off-site testing a special shielded bay will be required;
*that the operation is time consuming, expensive and there is a delay in obtaining the results;
*that skilled personnel are required both for operating the equipment and for analysing and interpreting the results; and
*operators may be exposed to radiation, very detailed safe systems of work will have to be prepared.

Front 5

In order to inspect the insulation condition on pipework 4m above ground level it is proposed, in the absence of availability of a mobile elevating work platform, to utilise a personnel cage lifted to the required height by a fork-lift truck (FLT). Outline the factors to be considered to ensure safety in the performance of this task
(Featured in July 2012)

Back 5

Factors associated with the design of the equipment
*The cage would have to be of adequate design and construction for the intended task,
*not exceed the width of the truck and
*be provided with toe boards and guard rails.
*Its total weight including that of personnel and equipment to be carried should not be more than 50% of the rated safe working load of the truck and
*the allowable safe working load should be clearly marked on the cage.
*Guards would have to be fitted to afford protection against moving parts on the mast of the truck.
Factors that need to be addressed to ensure the task was carried out in a safe manner
*The fork lift truck should be positioned on firm and level ground, with the mast vertical and the parking brake applied.
*The cage must be securely fixed to the forks and
*the driver should remain at the controls of the truck at all times and should not move it when the cage was elevated.
*Barriers should be positioned round the working area to protect against the possibilities of collision and passers-by being struck by falling materials.
*employees in the cage should wear safety harnesses, particularly if they might have to reach beyond the limits of the cage.

Front 6

A petrol storage tank in a bund containing three other similar tanks is overfilled during a transfer operation resulting in a large spillage of petrol into the bund. The petrol vapour is ignited from a remote source causing a catastrophic explosion and fire involving the whole of the installation. (a) Identify the design and construction measures that could have prevented such an event.

Back 6

*adequate segregation between adjacent tanks and the use of separate bunding;
*an interlocked pumping system with high level alarms with at least double redundancy of the alarms;
*level detection and vapour detector monitoring systems fitted in the bunds together with foam vapour suppression;
*the provision of remote shut down systems and a good standard of earthing and bonding.

Front 7

(b) Outline the range of measures that would be necessary to mitigate the effects of such an event.

Back 7

*provision of adequate fixed foam installations to spray the surface of pools in the bunded areas and spray deluge systems;
*the installation of foam monitors capable of reaching the tops of tanks;
*the erection of radiation walls between adjacent bunds to prevent other tanks being heated;
*an adequate supply of fire fighting water;
*the redundancy of water pressurisation;
*the installation of remotely operated pumps and valves to empty affected tanks;
*easy routes of access for fire fighters;
*the provision of drainage interceptors to minimise the environmental effects of fire water run-off;
*regular draining and cleaning to remove firewater from bunds;
*the preparation of an emergency plan to deal with such an event should it occur and
*the provision of training for operatives both in the content of the plan and the actions expected of them.

Front 8

Explain the term ‘fixed guard’ in relation to machinery safety and outline the factors to be considered in the design and use of fixed guards to ensure that persons are adequately protected.

Back 8

“Fixed guard” according to the definition in BSEN ISO12100 as a guard affixed in such a manner (eg by screws, nuts, welding) that it can only be opened or removed by the use of tools or destruction of the affixing means. It provides appropriate protection against mechanical hazards when infrequent or no access is required to dangerous parts of a machine during its normal operation.
A typical example of its use would be as a guard for a belt and pulley drive
Design features of a fixed guard
*Material of construction, which should be sufficiently robust to withstand the rigours of the workplace and be able to contain any ejected material, but still allow sight of the process when required;
*Method of fixing, usually requiring the use of a special tool for the guard’s removal;
*Need to ensure that any necessary openings in guards are such that they do not allow access to the dangerous parts (a function of the size of any opening in relation to the distance to the hazard);
*Need to address the possibility of the guard reverberating and exacerbating a noise problem.
Factors to be considered in the use of fixed guards include:
*Monitoring and supervision to ensure that the guard is not compromised,
*Safe systems of work for the carrying out of maintenance operations with the guard removed, and
*Provision of information and training for both operators and maintenance staff.

Front 9

Small electroplating companies often exhibit poor general standards of health and safety, made worse by the presence of conductive and corrosive fluids and humid, corrosive atmospheres.
(a) Describe the types of fault that may be found in fixed electrical systems under such conditions.

Back 9

Poor earth bonding; Damaged sockets and switchgear; Covers missing from junction boxes; Incompetent workmanship and inadequate excess current protection; Exposed conductors due to damaged insulation from corrosive; Short circuits caused by ingress of fluids; Corrosion of system parts; Unsuitability for use in wet & corrosive conditions

Front 10

(b) Outline the information relating to a fixed electrical system that will be required prior to a survey by a competent electrician.

Back 10

Type of equipment and its rating (operating voltage and current); IP classification (including measure of protect against ingress of water; Circuit diagrams and/manuals for the equipment; Details of any modifications made; Means of isolations and location; Earthing arrangements; Type and size of cables; Details on the operations of protective devices; Copies of previous inspection reports and repairs made/maintenance carried out

Front 11

(a) Outline the features of industrial robots that may have particular implications for safety.

Back 11

Sudden, rapid or unexpected movements; Aberrant behaviours e.g.. robot moving outside normal operating parameters; Dropped loads or ejected materials people have to enter area to rectify; Software problems which are difficult to detect; Dangers associated with teaching robot e.g.. may require close work with robot moving; Dangers from work being carried out e.g.. spot welding, stored energy; Dangers arising from maintenance activities e.g.. working in area close, robot may continue working; Failure of perimeter sensors leading to robot collisions with people or other equipment

Front 12

(b) Describe how the risk of injury to personnel working with or in the vicinity of industrial robots might be minimised.

Back 12

Carry out RA to identify hazards associated with robots and those at risk, evaluate the risk and identify controls required to reduce the risk to an acceptable level (eliminate or reduce); Restricting access by fixed fencing; Provision of interlock access point e.g.. pressure mats; Installation of light sensors e.g.. curtain or eye to detect motion and stop robot (automatic guarding); Provision of mechanical restrains; Use of audible start up warning; Procedures for restarting after interruption; Emergency stop systems; Introduction of safe systems of work e.g.. isolation lock out tag out before maintenance activities commence; Training relevant people in hazards associated with robot and precaution necessary; Introduction of monitoring system including audit and the keeping of records of maintenance and defects; Maintenance program; Routine guard checking procedure

Front 13

An independent tied scaffold to a new ten-storey office block has collapsed into a busy street.
(a) Outline the factors that may have affected the stability of the scaffold.

Back 13

Scaffold not erected as per original design; In-competent scaffold designers/erectors; Ground constructed on not being of load bearing capacity; Scaffold foundation being undermined by surface water or site works e.g. excavation; Incorrect use of fittings and/or use of damaged fittings; Standards were out of plumb or bent; Unauthorised/malicious alterations by incompetent people; Overloading of scaffold e.g. material storage; Impact e.g.. load suspended by crane/hit by plant vehicle; Severe weather e.g. excessive wind loading

Front 14

(b) Describe the main principles of scaffold design, erection and use to ensure the stability of such a scaffold.

Back 14

Use of competent persons; Designed to withstand required loading; Constructed of sound materials & fittings; Setting standards on base plates; Ensure joints are staggered; Fitting of longitudinal & diagonal bracing; Ledger braces at every other pair of standards; Vertical & horizontal ties no more than 8.5m apart and replaced by temporary ties if required to remove; Scaffold erected in position where traffic/plant impact likely barriers should be erected (protection); Ground erected on to have suitable load bearing capacity; Inspections carried out at regular intervals i.e. not exceeding 7 days and after change in conditions e.g. adverse weather conditions, after alterations etc.; Do not load beyond design capacity

Front 15

A leisure centre is planning to extend its existing building to incorporate childcare facilities on the ground floor and conference rooms to hire out to local businesses on the upper floors.
Outline the range of factors that would need to be addressed in order to ensure that the centre’s fire risk assessment remains adequate.

Back 15

*Need to consider the design of and the material to be used in the extension,
*Obtain competent advice from the fire authority
*Maintain existing means of escape during the construction phase.

Once the extension was in use, additional risk factors would include small children;
*Worried and possibly panicking parents if a fire was to occur;
*Persons under the influence of alcohol following events held in the conference facilities;
*Possible hazards of allowing smoking in the conference rooms
*Potential number of extra people to be evacuated.

This would call for additional precautions in terms of
*Escape routes and procedures and holding fire drills for the children and delegates;
*Extension to the existing alarm system with additional call points;
*Additional equipment such as emergency lighting, fire fighting appliances and the notices and signage that would be required.
*Appointment of additional fire marshals particularly with the likely presence of a number of vulnerable people (children) and
*Train employees in the revised procedures.

Front 16

(a) By reference to the Pressure Systems Safety Regulations 2000, explain what is meant by a ‘pressure system’.

Back 16

*Is a system comprising one or more pressure vessels of rigid construction and any associated pipe work and protective devices
*Pipework with its protective devices to which a transportable gas container maybe connected
*Pipeline and its protective devices which is liable to contain a relevant fluid. Example steam, gas at a pressure greater than 0.5 bar above atmospheric pressure when at a temp of 17.5 c or a gas dissolved in solvent at ambient temp which could be released from the solvent without the application of heat

Front 17

(b) A compressed air system is to be installed in a motor vehicle repair workshop. Outline the safety requirements that should be met before the system is commissioned.

Back 17

Siting of equipment to ensure protection from vehicles; Separation from flammable atmospheres; Protection of public from emission of noise; Establish maintenance and inspection procedures and written scheme of examination defines; Competent person to undertake a pre commissioning check; Provision of information and training for operators including safety feature, limits and correct operation of system; System design issues - Adherence to standards, Capacity, Materials of construction, Layout features, Fitting of pressure gauges, warning systems, Relief valves and drain lines, Marking of safety related info e.g. safe working pressure, Suitable guarding, Certificate of conformity and CE marked