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Wednesday, January 18, 2023

Confined Space Safety

OBJECTIVE

To establish safe work procedures for entering and working in a confined space.

SCOPE

This procedure applies to entry and work in confined spaces within the manufacturing site.

RESPONSIBILITY

General

In view of the hazards associated with working in confined spaces, all personnel who work in or support confined space work shall demonstrate a responsible attitude at all times during the work and in particular, shall ensure that:

  • Entry into a confined space is not permitted unless a Confined Space Entry Permit (CSEP) has been obtained (Appendix A – Confined Space Entry Permit).
  • The precautions stated on the CSEP and associated certificates are understood and observed.
  • The potential need for personal protective equipment whilst working in the confined space is understood and users are familiar in its use.

Personnel Entering Confined Spaces (Entrants):

  • Know and understand the CSEP before starting work, and abide by its conditions.
  • Stop work and exit the confined space immediately if conditions under which the permit was granted changes or if any danger is perceived.  Report this to the confined space attendant and supervisor

Supervisor (Requestor) of the person who is to enter or work in the confined space

Supervisors are responsible for ensuring that:

  • He /she applies for a CSEP for the person who is to enter or work in the confined space
  • The confined space is properly isolated before entry is permitted.
  • The atmosphere in the confined space has been fully tested for oxygen, toxic and flammable materials by an authorized Confined Space Assessor (CSA).
  • All personnel working within their area of supervision are properly instructed in the requirements of confined space entry, and work to these requirements.
  • That all the work crew are familiar with emergency procedures relevant to the confined space entry.
  • No work is carried out or is in progress without the prior approval of the authorised manager.

Confined Space Attendants

  • Attendants shall remain outside the confined space in order to:
  • Monitor persons entering and working in the confined space;
  • Maintain regular contact with the persons in the confined space  and when necessary assist them to evacuate should the need arise;  and
  • Initiate rescue as a member of confined space rescue team.

Confined Space Safety Assessor (CSA)

CSA shall be responsible for ensuring that:

The equipment they use is:

  • Suitable for the atmosphere to be tested.
  • Properly calibrated and maintained.

Gas testing is done according to CSEP requirements.

Authorised Managers (Approvers)

An appointed person overall in charge of work carried out in confined spaces on site whose duties include issuing and revoking entry permits, ensuring that confined spaces have been rendered as far as practicable free of hazards for safe entry and work, and that measures have been taken to eliminate or control the risk(s) identified in risk assessment conducted. It is necessary for him to review and assess the need to continue confined space work on a daily basis

Contractors / Sub-contractors

They shall ensure that the workmen put on the Personal Protective Equipment (PPE) during work.

DEFINITION

Confined Space

Any chamber, tank, manhole, vat, silo, pit, pipe, flue or other enclosed space, in which:

  • Dangerous gases, vapours, fumes are liable to be present to such an extent as to involve a risk of fire or explosion, or persons being overcome thereby;
  • The supply of air is inadequate, or is likely to be reduced to be inadequate, for sustaining life; or
  • There is a risk of engulfment by material 

Entrant

A person required to enter confined spaces to carry out inspections or work. 

Supervisor

The Supervisor of entrants who oversees entry and work in confined spaces. 

Confined space attendant

A person appointed to monitor entrants entering and working in a confined space.  He is also trained in confined space rescue and is able to carry out non-entry rescue should the need arise.

Rescue Personnel

Persons who carry out rescue work in confined spaces. 

Confined space safety assessor

A competent person appointed to test the atmosphere of confined spaces before entry, and to conduct periodic testing

Authorised Manager

A person who has overall control of all the work carried out in a confined space at a workplace 

PROCEDURE

Stage 1 Application by Supervisor

Before applying for a CSEP, the Supervisor shall make the following preparations:

A risk assessment shall be performed prior to any work occurring

in the confined space.

The following items will be evaluated for each confined space:

  • Past, current, and future use of the space;
  • Possible operations, work or activities in the confined space;
  • Physical characteristics, configuration and location of the space;
  • Any known hazards within or outside the space that could affect operations;
  • Existing or potential atmospheric conditions within or impacting the space;

Emergency response procedures

Every confined space into which entry is required shall, be opened

up, thoroughly purged and cleansed (if necessary),freed of gas and

liquids and thoroughly ventilated.

NB: The purging agent must not be pure oxygen or a gas mixture in a concentration of > 21% of oxygen by volume

Isolate all potentially hazardous services that are normally connected to the confined space to prevent 

(i) the introduction of materials, contaminants, agents or conditions that may be harmful to a person occupying the space, or; 

(ii) the activation or energising in any way of equipment or services that may pose a risk to the health or safety of a person inside the confined space.

Isolation can include:

  • De-energization and lockout/tagout
  • Blanking / Bleeding / isolation of pipes
  • Removal of mechanical belt/linkages

Electrical, hydraulic or mechanical equipment are to be disconnected or made inoperative.

Make arrangements for a confined space attendant (CSA) to be on standby outside the confined space to monitor and maintain regular contact with the entrant and effect non-entry rescue when required.

Appropriate PPE for use in confined spaces are provided:

  • Safety helmet;
  • Safety shoes;
  • Eye protection;
  • Hand protection;
  • Fall protection / lifelines;
  • Respiratory protection;
  • Protective and reflective clothing;
  • Other personal equipment, such as:
  • Pocket / personal gas detector
  • torchlight

Ensure entrant has donned on his safety harness and connected to the TRIS manual retrieval system

Put up barricades and signs where appropriate

Slippery surfaces are wiped dry

There is no excessive heat in the confined space

Sufficient and suitable (explosion proof) lightning for entry and work in confined space is provided

Portable handheld lighting if used, shall not be less than 50 lux and not exceed AC 55 volts and DC 110 volts

Forced ventilation in the form of blowers shall be used

All electrical equipment shall be protected by ELCB

An appropriate confined space rescue / retrieval system is set up to effect emergency rescue when the need arises.

No person shall be allowed to enter a confined space without a Confined Space Entry Permit.

All workers are briefed of hazards and familiar with emergency procedures

NB: Supervisors should use Appendix C as a checklist to consider actions required during the planning and preparation stages before work in confined space commences.

Stage 2 Evaluation by of confined space safety assessor (CSA)

On receipt of application for a CSEP, the CSA shall use a suitable and properly calibrated instrument to test the atmosphere of the confined space prior to entry by any person in the confined space.

The test shall include the following:

  • Oxygen content (19.5% to 23.5%)
  • Oxygen Deficiency

Oxygen level LESS than 19.5 % by volume shall be considered oxygen deficient. Personnel are not permitted to enter into or remain in oxygen deficient atmospheres unless:

Positive pressure breathing apparatus is worn;

The cause of the oxygen deficiency is identified and

The CSEP specifically identify and permit entry to the oxygen deficient space.

Oxygen Enrichment

Atmospheres containing more than 23.5% of oxygen by volume shall be considered oxygen enriched. Entry into oxygen enriched atmospheres is prohibited at all times and under all circumstances.

Flammable gas or vapor

Entry to a confined space is required without breathing apparatus, the maximum concentration of flammable gases must never exceed 1% LEL. Personnel are prohibited from entering or working in confined spaces without breathing apparatus where the concentration of flammable gases exceeds 1% LEL. 

Where flammable vapours are present at concentrations greater than 1% LEL but less than 10% LEL, then entry is only permitted when breathing apparatus is worn, and the full rules for wearing of breathing apparatus within confined spaces are followed. 

On no account should entry into a confined space be made, whether or not breathing apparatus is worn, where any flammable vapours present exceed 10% LEL. 

Hot Work is not permitted where flammable vapours greater than 0% LEL are detectable anywhere inside the confined space. 

Cold work, e.g. tank cleaning and inspection, is permitted up to a maximum permitted level of 10% LEL under strictly controlled conditions which must include the wearing of air supplied breathing apparatus. At this level of flammability, however, other contaminants may be present and Gas Testers will need to satisfy themselves that any relevant Permissible Exposure Limit (PEL) is not exceeded.

Concentration of Toxic gas / vapour where applicable

The levels of toxic substances of the confined space shall not exceed the permissible exposure levels (PEL) as specified in local regulations

Entry to spaces where the atmosphere contains contaminants above the PEL is not permitted under normal working conditions, irrespective of the type of respiratory protection used.         

The CSA shall be responsible to record the results of all CS atmosphere tests and keep them for a period of at least 5 years

When the CSA is satisfied that that entry into or work in the confined space can be carried out with due regard to the safety and health of persons who enter or work in confined spaces, he/she shall forward the permit to the Authorised Manager (AM) for approval.

When there is more than one worker in the confined space, at least one person shall be equipped with a personal gas monitoring device in working condition. 

NB: Limits for oxygen, flammable vapors and toxic contaminants are shown in Appendix B. 

NB: The CSA should use Appendix C as a checklist to consider actions required during the planning and preparation stages before work in confined space commences.

Stage 3 Approval by Authorised Manager (AM)

The Authorised Manager shall approve the confined space entry permit and forward it to the applicant if he /she is satisfied that:

The level of oxygen in the confined space is within the range of 19.5% to 23.5% by volume;

The level of flammable vapors in the confined space is less than 10% of its lower explosive limit;

The levels of toxic substances in the atmosphere of the confined space do not exceed the permissible exposure levels as specified in local regulations;

The confined space is adequately ventilated;

Effective steps have been taken to prevent any ingress of dangerous gases  or any other dangerous substances into the confined space; and

All reasonably practicable measures have been taken to ensure the safety and  health of persons who will be entering or working in the confined space

Before forwarding the approved confined space entry permit (CSEP), it is the responsibility of the AM to make and retain a copy of the CSEP.

Stage 4a Posting of Entry Permit

When the Supervisor (applicant) receives the approved CSEP from the AM, it shall be his / her duty to:

Post a copy of the permit at the entrance to the confined space and ensure that the permit is not removed until the permit has expired or revoked or the work is completed.

Ensure that identification tags or badges of all entrants are displayed

Monitoring Confined Space Work

Any person who is aware of any work carried out in the workplace which is incompatible with any work carried out in the confined space have a duty to immediately report it to his Supervisor, the Workplace Safety and Health Officer or the AM.

The Supervisor is responsible for ensuring that work conditions remain safe at all times.

The Supervisor shall also ensure that a team trained in confined space rescue operations is on-site as long as work in being carried out in the confined space.

Workers shall observe the following while carrying out work in the confined space:

Never smoke in confined space

Always maintain communication with attendant while working in a confined space

  • Never use defective electrical connection / tools which may cause fire.
  • Never enter into a confined space if there is inadequate lighting
  • Ensure that lighting is adequate
  • Take your food outside the confined space
  • Never stay / rest in a confined space.

The atmosphere shall be tested by the CSA every 2 hrs if gas continuous monitoring is not performed in the confined space.

If there are 2 or more persons in the confined space, at least 1 person must have on a suitable gas detector that continuously monitors the atmosphere.

If a hazardous atmosphere is detected by the gas detector, the alarm will go off.  All persons must evacuate the confined space immediately.

No person shall re-enter the confined space until a new confined space entry permit is issued by the AM for the confined space.

Stage 4b Notification of Completion / Termination of Work

The Supervisor shall remove the permit based on the following conditions:

  • Permit expired;
  • Permit revoked;
  • Work completed; or whichever is earliest

The Supervisor is responsible for informing the AM immediately after the permit is removed.

Confined Space Rescue Operations Plan (See Appendix E for detailed plan)

EHS shall maintain a written confined space rescue operations plan that includes rescue equipment

  • The Rescue Operation Plan shall include:
  • Names of designated rescue personnel;
  • Methods of rescue to retrieve persons inside a confined space;
  • The type equipment necessary and available for rescue; and
  • Means to summon designated rescue personnel

Emergencies     

If a hazard arises within the confined space, personnel in the space shall immediately exit and contact his/her Supervisor and the EHS Officer. The Supervisor, with assistance from the EHS Officer, will re-evaluate the space to determine the appropriate course of action.

Personnel shall immediately leave the space when any of the gas monitor alarm(s) are activated.

If there is any non-movement of personnel in the confined space, the confined space attendant will make a verbal check.  If there is no response, the attendant shall inform the Supervisor and EHS Officer via walkie talkie and initiate rescue in accordance to Appendix E – Confined Space Rescue Operations Plan.

Training              

Management shall ensure that all personnel who are directly or indirectly involved in the confined space or work have been appropriately trained.  These include:

  • Confined space entrants;
  • Attendants;
  • Supervisors;
  • Rescue personnel;
  • Safety assessors and
  • Authorised managers 

All appointed rescue personnel shall have received adequate training in rescue operation, including first aid and proper usage of PPE and rescue equipment

Documentation and Record Keeping

EHS shall maintain a register of confined spaces for the company and evaluate all procedures of confined space work and entry at the manufacturing site.

All CSEP and gas test records shall be retained by the appropriate responsible parties (AM and CSA) for at least 5 years

All training records shall be retained by HR for at least 5 years


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