Confined space safety entry interview questions and answer.
What is a confined space?
Confined Space refers to
any place, including any vessel, tank, container, pit, bund, chamber, cellar or
any other similar space which, by virtue of its enclosed nature, creates
conditions that give rise to a likelihood of an accident, harm or injury of such
a nature as to require emergency action due to
- the
presence or reasonable foreseeable presence of:
- flammable or explosive atmospheres
- harmful gas, fume or vapour
- free flowing solid or an increasing level of liquid
- excess of oxygen
- excessively high temperature - the lack
or reasonably foreseeable lack of oxygen
What are the key characteristics which
define a confined space?
The key characteristics
of a confined space are:
- the space
must be substantially enclosed
- there must
be a risk of at least one of the hazards listed above occurring within the
space
- the risk
of serious injury from the hazard must be created by virtue of the
enclosed nature of the space
- the
potential injury must be serious and be such as to require emergency
action to rescue the person involved.
What are the hazards associated with confined spaces?
The hazards associated
confined spaces include:
- Toxic
Atmosphere
A toxic atmosphere may cause various acute effects, including impairment of judgement, unconsciousness and death. A toxic atmosphere may occur due to the presence or ingress of hazardous substances. These substances may be present in the Confined Space for various reasons such as:
- remaining from previous processing or storage
- arising from the disturbance of sludge and other deposits
- the presence of a fire or flames within the space
- seepage from improperly isolated adjoining plant
- formation during the work processes carried out in the space
- being released from under scale and in brickwork as a result of the work process - Oxygen
Deficiency
Oxygen can be lacking a confined space for the following reasons:
- displacement of air by another gas
- various biological processes or chemical reactions (such as rotting of organic matter, rusting of metals, burning, etc)
- absorption of air onto steel surfaces, especially where these are damp - Oxygen
Enrichment
An excess of oxygen, in the presence of combustible materials, results in an increased risk of fire and explosion. Some materials, which do not burn in air, may burn vigorously or even spontaneously in an enriched oxygen atmosphere. - Flammable
or Explosive Atmospheres
A flammable atmosphere presents a risk of fire or explosion. Such an atmosphere can arise from the presence in the confined space of flammable liquids or gases or of a suspension of combustible dust in air. If a flammable atmosphere inside a confined space ignites, an explosion may occur, resulting in the expulsion of hot gases and the disintegration of the structure. - Flowing
Liquid or Free Flowing Solids
Liquids or solids can flow into the confined space causing drowning, suffocation, burns and other injuries. Solids in powder form may also be disturbed in a confined space resulting in an asphyxiating atmosphere. - Excessive
Heat
The enclosed nature of a confined space can increase the risk of heat stroke or collapse from heat stress, if conditions are excessively hot. The risk may be exacerbated by the wearing of personal protective equipment or by lack of ventilation
What are the legal requirements in regard
to confined space entry?
The Safety, Health and
Welfare at Work (Confined Spaces) Regulations 2001 cover all work in relation
to confined spaces.
Regulation 5 states that:
- A person
shall not carry out work in Confined Spaces if it is reasonably practical
that it could be avoided
- If the
work must be carried out Hazard Identification and Risk Assessment must be
carried out prior to the work commencing
- A person
shall not enter a confined space unless there is a system of work in place
that has been planned, organized, performed and maintained so as to render
that work safe and without risk to health
- Anyone
entering a confined space must be provided with appropriate information,
training and instruction appropriate to the particular characteristics of
the proposed work activities
What are legal requirements in relation to Emergency Arrangements for confined spaces?
Regulation 6 of the
Confined Space Regulations 2001 states that:
- A person
shall not enter a confined space unless there is a suitable emergency
arrangements have been made which are appropriate to the confined space in
question
- The
emergency arrangements shall include:
- all practical measures necessary to ensure the health and safety of those taking part in the rescue
- the provision of a suitable and reliable means of raising the alarm in the event of an emergency
- having all necessary rescue equipment nearby and in a well maintained, good condition
- the provision of information, instruction and training to all involved in rescue procedures
- the provision of equipment and training for resuscitation procedures if there is a foreseeable risk that they will be needed.
What must I look for in a confined space
risk assessment?
When carrying out a risk
assessment it is important to ensure that all risks associated with the hazards
above are evaluated and controlled. When carrying out a risk assessment the
following questions should be asked:
- What could
be inside the space that would pose a risk?
- Contents?
- Oxygen Deficiency?
- Previous Contents?
- Oxygen Enrichment?
- Residues?
- Structure and Layout?
- Contamination? - What will
be created due to the work carried out in the space?
- Sources of Ignition?
- Flammable Substances? - What‘s
outside the space that might pose a risk during the proposed work?
- Inadequate Isolation?
- Inadvertent Operation Of Plant?
- Nearby Work Activities?
Are there any exemptions from the Safety,
Health and Welfare (Confined Spaces) Regulations 2001?
Yes. The regulations do
not apply to any place below ground in a mine (as defined by the Mines and
Quarries Act 1965) or to any diving operations.
What are the key elements of a safe system
of work for a confined space?
The key elements to be
considered when drawing up a safe system of work are:
- Competence,
training, supervision and suitability
- Permit-to-work
procedure
- Gas
purging and ventilation
- Dangerous
residues
- Testing
and monitoring of the atmosphere
- Mechanical,
electrical and process isolation
- Respiratory
protective equipment
- Other
personal protective equipment
- Safe use
of work equipment
- Communications
- Access and
egress
- Flammable
or explosive atmospheres
- Combustible
materials
What is a permit-to-work procedure?
A permit to work
procedure is a means of achieving effective control of a system of work through
formal written documentation known as a permit to work form. The
essential components of a permit-to-work system include:
- A written
procedure, which sets out how the system is to operate and clearly defines
who may authorize particular jobs and who is responsible for specifying
and implementing the necessary precautions
- A form,
known as the "permit-to-work form", which becomes a written and
signed statement ensuring both the establishment of safe conditions for
the work to commence and the maintenance of safe conditions for the
duration of the work, including the provision of emergency arrangements
- A method
of informing the persons carrying out the work of the exact identity,
location, nature and extent of the job, the hazards involved and the
precautions to be taken, and
- A system
for ensuring the safe hand-back of the workplace after the job is
completed and, in the case of confined space entry, after the space is vacated
