WORKING IN CONFINED SPACES

General duties of employers and employees

Duties of employers

Under all NOHSC standards and codes, employers have a duty to:

• implement a systematic process of hazard identification, risk assessment, risk control and review in the workplace;
• make sure employees receive appropriate training, instruction and supervision, including induction and ongoing training;
• obtain and provide appropriate information;
• consult with employees likely to be exposed to risks, and with their health and safety representatives;
• keep appropriate records.

Additional or more specific requirements apply in some areas.

Hazardous substances;

• HIV/AIDS and hepatitis B;
• major hazard facilities;
• plant;
• working in confined spaces.

Duties of employees

Under all NOHSC standards and codes, employees have a duty to:

• comply, as far as they can, with all activities carried out in accordance with the standard
• report to their employer anything that might affect the employer’s compliance with the standard.

 

What is a Confined Space?

Confined spaces are fully or partially enclosed areas which aren’t designed to be normal places of work, and where entry and exit are restricted. They include things like storage tanks, silos, pits or degreasers, pipes, shafts or ducts, or confined space onboard ships.

Working inside spaces like this (including putting one’s head or upper body inside them) can be dangerous for various reasons. Fatalities or severe injuries can occur because:

• there’s not enough oxygen, or too much oxygen (leaking from an oxygen supply, for example);
• the atmosphere or surfaces inside are contaminated,
• steam, water, or other gases or liquids may enter the space in an uncontrolled way;
• there is a risk of suffocation (eg by grain, sand, flour), electrocution, explosion or fire.

Confined spaces can increase the risk of injury from other hazards too—such as equipment operating in the space, noise (tasks such as hammering may become louder), radiation, or temperature (conditions may be too hot or too cold as a result of the work process or the weather conditions, bad ventilation or inappropriate clothing).

The constraints of the space can also make manual handling injuries and falls more likely.

Standards and codes of practice

Joint National Standard for Safe Working in a Confined Space Australian Standard AS2865-1995 (produced jointly by Standards Australia and the NOHSC)

A set of requirements for employers (and designers) about: how to eliminate or minimise the need to enter confined spaces; and how to protect the health and safety of anyone who needs to enter a confined space.

Special duties

In addition to the duties outlined previously, employers must also:

• ensure that any modifications to a confined space do not make entry and exit more difficult;
• ensure that noone enters a confined space without an entry permit;
• ensure that appropriate rescue and first aid procedures are planned, established and rehearsed.
• keep the following records:

- entry permits (for one month);

- risk assessment reports (for five years);

- training (for the term of the employee’s employment).

The national standard also sets out various duties which apply to people who design, manufacture or supply confined spaces.

Identifying hazards and assessing risks

Getting Started

Start by listing the confined spaces in your workplace, noting any work associated with them (regular maintenance, for example) and whether it is necessary to enter the space to perform the work.

You’re looking for:

• hazards associated with entering the confined space itself, as well as
• hazards associated with what is actually to be done inside the space.

Use checklists, perhaps based on those in the accompanying show.

Controlling risks

1. Options which eliminate the hazard

The best option is eliminate the need to enter the confined space at all—use tanks designed to be self-cleaning, for example, or equipped with observation windows.

2. Options which minimise the risk

Substitution: If it’s absolutely necessary to work in a confined space, substitutions can be made to ensure the work itself is as safe as possible—using a non-flammable solvent instead of a flammable one, for example, or a brush instead of aerosol application.

Isolation: The space should be isolated from all potentially hazardous services to prevent accidental activation of things like machinery, accidental energisation, or accidental introduction of contaminants or other unwanted materials through piping, vents, drains etc.

Engineering controls may include mechanisms for lockouts, for cleaning contaminants from the confined space, for monitoring conditions inside the space, or for ensuring the atmosphere (including oxygen level, pressure and temperature) is safe (and remains safe all the time anyone is inside the space).

Try to get the design right in the first place: If the space can’t be designed to eliminate the need for entry, the design of the space should minimise the risk to anyone entering or working inside it (including providing safe means of exit and entry).

3. Backup controls

Safe work practicesshouldbe designed to ensure that, wherever a risk to health and safety has been identified:

• noone enters a confined space without an entry permit, and without at least one person standing by outside;
• suitable signs are erected outside while people are inside;
• the confined space is only returned to service after making sure (and acknowledging in writing) that the work is finished and noone remains inside,
• suitable procedures are in place for rescue, first aid and fire suppression.

Personal protective equipment such as respiratory equipment, safety harnesses and protective clothing, may be used when risks cannot be sufficiently controlled using other means, or as a temporary measure until other controls can be implemented.

RISK FACTORS FOR WORKING IN CONFINED SPACES

Risk factors are things which could affect the risk of harm from working in confined spaces

• Nature of the confined space

Risk increases with:

• unsound or insecure structures
• low visibility or lack of illumination
• size and shape which restricts movement
• difficult or obstructed entry/exit points
• presence ofmoving equipment which may crush, or trap a person
• potential for uncontrolled introduction of steam, water, or other gas or liquid.

·         State of the atmosphere inside the space

Risk increases with:

• presence of inert gases which dilute air
• presence of contaminants (gases, vapours, fumes, particulates)
• presence of explosive or volatile substances
• lack of ventilation
• higher or lower than normal temperature and/or atmospheric pressure
• Substances currently or last contained

Risk increases with:

• substances (either organic or inorganic) which have been slowly oxidising (using available oxygen)
• substances which absorb oxygen (grains, chemicals, soils)
• substances which leave contaminants on surfaces (solids, liquids, sludges)
• presence of solid materials (eg grains, sand, flour, fertiliser) which can cause suffocation
• Work in adjacent areas
• Risk may increase with hot work or use of moving equipment such as forklifts in adjacent areas

·         The requirements of the work to be done

Risk increases with:

• the need for physical activity, which increases the body’s use of oxygen and raises body temperatures
• the use of equipment which could leak excess oxygen into the atmosphere
• the use of equipment which could make entry/exit difficult
• the use of processes which release contaminants (eg painting with toxic or flammable substances, welding or brazing with metals producing toxic fumes)
• the use of processes involving combustion(which use up oxygen)
• the need for hot work
• the use of equipment which produces radiation (eg lasers, welders, radiation gauges)
• processes producing noise which may be amplified by the confined space

      Number of people inside the space

• Risk increases the more people there are inside (although two may be safer than one in some circumstances??)

        The length of time spent inside the space

• Risk increases the longer or more often work is required inside a confined space.

    Number of people outside the space

• There should be enough people outside to maintain essential equipment, monitor progress and carry out rescue procedures

       Fitness, skills and experience of employees

• Risk increases for inexperienced or untrained employees.
• Use and effectiveness of control measures

Training tips

Training programs about working in confined spaces should cover:

• hazards associated with such working conditions;
• risk assessment procedures and control measures;
• emergency procedures;
• selection, use, fitting and maintenance of safety equipment.

Training should be provided for people working in or on confined spaces, as well as people who:

• are on standby during confined space work
• issue entry permits;
• design and lay out the workplace;
• manage or supervise people working in or near confined spaces,
• maintain equipment used for confined space work;
• buy, distribute, fit or maintain personal protective equipment
• are involved in rescue and first aid procedures.

Advice and training materials can be obtained from State and Territory governments, and employer and employee groups.