PROPERTY & ESTATES GROUP

Transcription

1 PROPERTY & ESTATES GROUP SAFE WORKING PROCEDURE WORKING IN CONFINED SPACES Purpose of Document This document describes SRUC s policy and procedure for working in confined spaces. It applies to contractors and SRUC staff, and helps ensure compliance with the Confined Spaces Regulations 1997.

2 CONTENTS 1. INTRODUCTION Definitions Identifying Confined Spaces Potential Hazards within Confined Spaces Security of Confined Spaces Competent Person WORKING IN CONFINED SPACES Safe System of Work PEG Authorised Person Contractors Communications Testing / Monitoring the Atmosphere Gas Purging Ventilation Removal of Residues Isolation from Mechanical and Electrical Equipment Selection and use of Suitable Equipment Personal Protective Equipment and Respiratory Protective Equipment Breathing Apparatus Rescue Harnesses Access and Egress Emergency Plan Permit-to-Work EMERGENCY PROCEDURES Rescue and resuscitation equipment Shut down First-aid procedures Fire safety Page 2

3 1. INTRODUCTION This document should be read in conjunction with HSE (L101) Approved Code of Practice HSE_ACOP 101.pdf 1.1 Definitions Confined Space A confined space has two defining features. Firstly, it is a place which is substantially (though not always entirely) enclosed and, secondly, there will be a reasonably foreseeable risk of serious injury from hazardous substances or conditions within the space or nearby. A confined space is any enclosed workplace where there is a risk of death or serious injury from hazardous substances, or dangerous conditions such as a lack of oxygen. A confined space always requires a permit-to-work, no matter what the work is. Enclosed Space An enclosed space can only be defined if it falls outside the scope of the confined space definition e.g. is well ventilated and has no identified specified risks. It is essential to consider that these areas may as a consequence of the work involved become a confined space. This would occur if a specified risk was foreseeable due to the work process such as more than one person working within the enclosed space; and /or hot works adding fumes and heat within the working space. The method statement of work to be conducted within these areas should be thoroughly checked and a specific risk assessment applied. Therefore an area while categorised as an enclosed space never precludes it becoming a confined space under certain conditions and in such cases all procedures applicable for confined space working apply including the general principle that work within these areas should avoided wherever possible. Where minor and short term works are required and pose no foreseeable hazards then the issue of permits to work would only be necessary for such areas but it is important to actively monitor works within these areas to ensure that a safe system of work is being adopted. 1.2 Identifying Confined Spaces Some confined spaces are fairly easy to identify, for example, enclosures with limited openings, such as: Storage tanks and silos Reaction vessels Enclosed drains Sewers Open-topped chambers Vats Combustion chambers in furnaces and so on Ductwork Unventilated or poorly ventilated rooms It is not possible to give a comprehensive list of confined spaces. Some places might become confined spaces when work is carried out, or during their construction, fabrication or subsequent modification. All major works involving work within these areas should be contracted out to specialist contractors and specific risk and method statements should be provided to PEG by the Page 3

4 contractor at least three days in advance of programmed works starting. This time is to enable sufficient planning of the work and to thoroughly evaluate the risk and method statements provided by the contractor to undertake the work. Only in exceptional circumstances should the three day rule be relaxed and in such cases the Regional Buildings Manager must ensure that the risk and method statements submitted by the contractor complies fully with The Confined Space Regulations 1997 and HSE (L101) Approved Code of Practice. Where PEG staff have to enter a designated confined space then a specific risk assessment (not a generic) must be completed and a permit-to-work must be authorised prior to entry. Additionally, measures regarding communications and rescue plans must be prepared in advance prior to entry. The use of a (calibrated) personal gas detector while working within the area is a mandatory requirement for all persons entering any designated confined space and must form part of the PPE used in such areas. It would be anticipated that PEG staff would only enter such areas for very short duration and would be primarily for inspection purposes only. If in-house minor works are to be conducted then a specific method statement must be agreed by the Regional Buildings Manager and a safe system of work applied to the area. 1.3 Potential Hazards within Confined Spaces A lack of oxygen. This can occur, for example: Where there is a reaction between the soil and the oxygen in the atmosphere. When groundwater acts on chalk and limestone to produce carbon dioxide, which displaces normal air. When rust forms inside steel tanks and vessels. Poisonous gas, fumes or vapour which can build up in sewers and manholes, and in pits connected to the system. Enter tanks or vessels from connecting pipes. Leak into trenches and pits on contaminated land, such as old refuse tips and old gas works. Liquids and solids which can suddenly fill the space, or release gases into it, when disturbed. Fire and explosions (for example, from flammable vapours, excess oxygen and so on). Residues left in tanks, vessels and so on, or remaining on internal surfaces, which can give off gas, fumes or vapour. Dust which might be present in high concentrations, for example, in silos. Hot conditions, leading to a dangerous increase in body temperature. Some of these adverse conditions might already be present in the confined space. However, some might arise as the work progresses, because of, for example: The nature of the work being carried out. The ineffective isolation of plant nearby, such as leakage from a pipe connected to the confined space. Page 4

5 The enclosure and working space might also increase other hazards arising from the work being carried out, for example: Machinery being used might require special precautions, such as dust extraction for a portable grinder, or precautions against electric shock. Gas, fume or vapour can arise from welding, or from using volatile or flammable solvents, adhesives and so on. Escape or rescue in an emergency will be more difficult if access to the space is through a restricted entrance such as a manhole (see Section 3, Emergency Procedures). This list is not exhaustive and care should be taken to identify any local factors which may increase the risk of working within such areas. 1.4 Security of Confined Spaces You must secure all access points to the confined space against unauthorised entry and position a warning sign: - Strictly No Entry Without a Permit-to-Work 1.5 Competent Person For the purposes of this document, a competent person is someone who has sufficient training, experience and familiarity with the relevant processes, plant and equipment to: Understand the potential hazards involved in working in confined spaces at SRUC sites Be able to devise the precautions necessary to comply with the Confined Spaces Regulations 1997 and the HSE Approved Code of Practice Regulations and Guidance (L101) Page 5

6 2. WORKING IN CONFINED SPACES No person at work shall enter a confined space to carry out work for any purpose unless it is not reasonably practicable to achieve that purpose without such entry Regulation 4 - Confined Space Regulations Always avoid confined space working if an alternative to this is possible. If any work involves operating in any confined (or enclosed) space a competent person must have carried out a suitable and sufficient risk assessment. In complex cases, or where specific expertise is required, more than one competent person is required to carry out the risk assessment. If a specified risk is identified then the Confined Spaces Regulations 1997 apply and impose specific legal duties. Review again the requirement to conduct work within the confined space you must only assign work within a confined space if an alternative is not reasonably practicable and the review process should be written and retained on the work file. For example repairs to leaking pipework can the existing services be re-routed and the confined space installation decommissioned? If this is not reasonably practicable to do then confined space working is acceptable but the decision process should be clearly stated and prove that a logical process was adopted for the assessment. Follow a safe system of work (see Section 2, Safe System of Work) Put in place adequate emergency arrangements before the work starts (Section 3, Emergency Procedures) 2.1 Safe System of Work Risk assessment must have sufficient control measures in place to reduce all risks to manageable levels. The Contractors Method Statement must specify a Safe System of Work to be followed in accordance with Regulation 4 of HSE (L101) 2.2 PEG Authorised Person The authorised person issuing the permit to work is responsible for ensuring that the necessary safety precautions are taken and for checking safety at each stage of the work. 2.3 Contractors The SRUC Management of Contractors Policy should be strictly applied to all contractors undertaking confined space works. Specifically detailed information must be supplied and thoroughly vetted to establish competence. Do they have sufficient experience of the type of work to be carried out? What training have they received? Where risk assessment highlights exceptional constraints as a result of the physical layout, are individuals of suitable build? Page 6

7 Do you need to consider other factors, such as claustrophobia, fitness to wear breathing apparatus (in the event of an emergency), or medical advice on an individual's suitability? 2.4 Communications Ensure an adequate communications system is established to enable people inside and outside the confined space to communicate with each other, and to summon help in an emergency. 2.5 Testing / Monitoring the Atmosphere Testing of the atmosphere of the confined space should be done in the presence of the Regional Buildings Manager (or other PEG manager) with a calibrated gas detector and a permit-to-work must only be issued if the area is deemed safe to enter. Oxygen content Flammable gases Toxic gases, vapours and dusts All persons entering a confined space to have a (calibrated) personal gas detector forming part of their PPE. 2.6 Gas Purging Where the risk assessment has identified the presence or possible presence of flammable or toxic gases or vapours there may be a need to purge the gas or vapour from the confined space. This can be done with air or an inert gas where toxic contaminants are present, but with inert gas only where there are flammable contaminants. You can only use inert gas for purging flammable gas or vapour because any purging with air could produce a flammable mixture within the confined space. Where purging has been carried out, the atmosphere will need to be tested to check that purging has been effective, and that it is safe to breathe before allowing people to enter. Hot works within confined spaces should always be a last resort and other engineering solutions should always be considered as an alternative. Warning: No internal combustion engine (petrol or diesel) to be used within a confined space. Where portable gas cylinders are used (as in the case of hot works) then a further risk assessment should be undertaken to control risk caused by such use. 2.7 Ventilation Some confined spaces may require mechanical ventilation to provide sufficient fresh air to replace the oxygen that is being used up by people working in the space, and to dilute and remove gas, fume or vapour produced by the work. This can be done by using a blower fan and trunking and/or an exhaust fan or ejector and trunking (provided that there is an adequate supply of fresh air to replace the used air). Fresh air should be drawn from a point where it is not contaminated either by used air or other pollutants. Never introduce additional oxygen into a confined space to sweeten the air as this can lead to oxygen enrichment in the atmosphere that can render certain substances (e.g. grease) liable to spontaneous combustion, and will greatly increase the combustibility of other materials. Oxygen above the normal concentration in air may also have a toxic effect if inhaled. Page 7

8 2.8 Removal of Residues Cleaning or removal of residues is often the purpose of confined space work. In some cases residues will need to be removed to allow other work to be undertaken safely. Appropriate measures should be taken where risks from the residues are identified. For example, dangerous substances (such as hazardous gas, fume or vapour) can be released when residues are disturbed or, particularly, when heat is applied to them. 2.9 Isolation from Mechanical and Electrical Equipment Equipment should be mechanically and electrically isolated if it could otherwise operate or be operated inadvertently unless the risk assessment specifically allows for power to remain on. Confined spaces will often need to be isolated from ingress of substances that could pose a risk to those working within the space. An effective method is to disconnect the confined space completely from every item of plant either by removing a section of pipe or duct or by inserting blanks. If blanks are used, the spectacle type with one lens solid and the other a ring, makes checking easier. When disconnection in this way cannot be done one alternative is a suitable, reliable valve that is locked shut, providing there is no possibility of it allowing anything to pass through when locked, or of being unlocked when people are inside the confined space. It is the duty of the authorised PEG manager to ensure that all isolations are effectively in place prior to any work commencing Selection and use of Suitable Equipment Any equipment provided for use in a confined space requires to be suitable for the purpose. Where there is a risk of a flammable gas seeping into a confined space and which could be ignited by electrical sources (e.g. a portable hand lamp), specially protected electrical equipment needs to be used, for example, a lamp certified for use in explosive atmospheres. Note that specially designed low voltage portable lights, while offering protection against electrocution, could nevertheless still present ignition sources and are not in themselves safer in flammable or potentially explosive atmospheres. All equipment should be carefully selected bearing in mind the conditions and risks where it will be used. Equipotential earth bonding should be considered to prevent static charge build-up. In addition to isolation mechanical equipment may need to be secured against free rotation, as people may tread or lean on it, and risk trapping or falling. Non-sparking tools and specially protected lighting are essential where flammable or potentially explosive atmospheres are likely. In some confined spaces (such as inside metal tanks), suitable precautions to prevent electric shock include: Using extra low voltage equipment (typically less than 25V) Using residual current devices, if necessary 2.11 Personal Protective Equipment and Respiratory Protective Equipment So far as is reasonably practicable you should ensure that a confined space is safe to work in without the need for personal protective equipment (PPE) and respiratory protective equipment (RPE) which should be a last resort, except for rescue work (including the work of the emergency services). Use of PPE and RPE may be identified as necessary in your risk Page 8

9 assessment, in which case it needs to be suitable and should be provided and used by those entering and working in confined spaces. Such equipment is in addition to engineering controls and safe systems of work. The type of PPE provided will depend on the hazards identified but, for example, might include safety lines and harnesses, and suitable breathing apparatus. Take account of foreseeable hazards that might arise, and the need for emergency evacuation. The contractors risk and method statement must address these issues and PPE / RPE standards should be clearly stated Breathing Apparatus The use of this equipment must be specifically included within the Contractors Risk and Method Statement Rescue Harnesses The use of this equipment must be specifically included within the Contractors Risk and Method Statement. Lifelines attached to harnesses must be run back to a point outside the confined space Access and Egress Wherever possible allow quick, unobstructed and ready access. The means of escape must be suitable for use by the individual who enters the confined space so that they can quickly escape in an emergency. Suitable means to prevent access should be in place when there is no need for anybody to work in the confined space. The safe system of work should ensure that everyone has left the confined space during boxing-up operations particularly when the space is complicated and extensive, for example in boilers, cableways and culverts where there can be numerous entry/exit points. The size of openings to confined spaces needs to be adequate. Openings affording safe access to confined spaces, and through divisions, partitions or obstructions within such spaces, need to be sufficiently large and free from obstruction to allow the passage of persons wearing the necessary protective clothing and equipment, and to allow adequate access. Make sure the entrance is sufficiently large to allow workers wearing all the necessary equipment to climb in and out easily, and provides ready access and egress in an emergency Emergency Plan The written method statement must have an Emergency Plan included which fully complies with HSE (L101) Regulation (5) 2.16 Permit-to-Work Permit- to- Work is mandatory for all confined space working Reference - Safe Systems Permits-to-Work - PEP1-11-xx Permit-to-Work: Confined Spaces - PTW2-17-xx Page 9

10 3. EMERGENCY PROCEDURES Arrangements for emergency rescue depend on the nature of the confined space, the risks identified and the likely nature of the emergency rescue itself. These should be fully detailed within the Emergency Plan and details of emergency contacts must be displayed within the work area prior to work commencing. Emergency Actions Dial the emergency number to summon assistance Give the message clearly, and include details of: Location The nature of the emergency Type of assistance required If required obtain first aid assistance while waiting for emergency services to attend. 3.1 Rescue and resuscitation equipment The rescue plan associated with the safe system of work must specify the type of rescue and resuscitation equipment to be supplied on site. Fire and Rescue Service should immediately be contacted if an incident occurs and will provide assistance with the rescue, but they are not primarily responsible for the removal of casualty from a confined space. 3.2 Shut down PEG staff should immediately shut down and isolate any associated plant in emergency situations. 3.3 First-aid procedures Trained first-aiders must be available to make proper use of any necessary first-aid equipment provided. However they must not enter any confined space unless they are trained and competent to do so. 3.4 Fire safety Fire safety should be integral with the risk and method statement approved for the work. If there is a risk of fire, you will require the appropriate fire extinguishers within the confined space, at the entry point, and an additional hot works permit will be required to be issued prior to work proceeding. Page 10