Tuesday, June 16, 2009

An Overview of the Hazard Identification and

Step 1 – Decide who should be involved
You have responsibility for carrying out the hazard identification and the risk assessment
under Regulations 404 and 405.
You should ensure that any person carrying out the assessment is familiar with the
requirements of the Regulations and has a practical understanding of the how the dangerous
goods are stored and handled at the premises.9
A single person such as the works manager or works chemist may be suitably competent to
perform simple assessments, while in more complex cases, several people representing a
variety of skills will probably need to be involved in collecting and assessing the information.
Consult your relevant employees and their health and safety representatives.
Step 2 – Hazard Identification
Identify all dangerous goods at the premises
Identify all dangerous goods stored and handled at the premises and any dangerous goods
generated during any manufacturing process. All of these dangerous goods must be
considered in the hazard identification and subsequent risk assessment process.
The following information should be assembled for each of the dangerous goods present:
· the name of the dangerous goods;
· the Class, Subsidiary Risk and Packing Group;
· if the dangerous goods are in packages, the sizes and numbers of packages of each size;
and
· if the dangerous goods are in bulk, the identification numbers, capacity and average
quantity of dangerous goods in each bulk container.
Obtain information about the dangerous goods
MSDS and markings on packages for all dangerous goods supplied to the workplace should
be reviewed to obtain information on the chemical and physical properties, hazardous
properties, precautions for use and safe handling requirements for the dangerous goods.
Sources of information
Sources of information include:
9 If you are considering contracting the services of external consultants, ensure that they have the expertise
and experience to do the job competently. Guidance on the selection and effective use of dangerous goods
and occupational health and safety consultants can be obtained from the Victorian WorkCover Authority
publication Selecting an Occupational Health and Safety Consultant – A Guide for Workplaces.
Professional associations, such as the Institution of Engineers Australia and the Royal Australian
Chemical institute, may also be able to provide guidance on persons qualified to perform dangerous
goods assessments.
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· MSDS obtained from manufacturers and suppliers;
· package markings;
· class information (information about the Class of the dangerous goods indicates a key
hazard of the dangerous goods but in itself is generally not sufficient because there are
significant differences in the chemical and physical properties of individual products
within the class);10
· package labels (information on the package itself will generally be insufficient to cover
anything more than the most basic use of the product).11
Other helpful sources of information include:
· National Industrial Chemical Notification and Assessment Scheme (NICNAS) Summary
Reports. NICNAS Summary Reports have been produced for every dangerous goods
notified and assessed under the Commonwealth Industrial Chemical (Notification and
Assessment) Act 1989;
· Sources listed in Appendix 1 of the National Code of Practice for the Preparation of
Material Safety Data Sheets;
· the Victorian WorkCover Authority (WorkCover);
· NOHSC (formerly known as Worksafe Australia);
· trade unions and employer associations;
· industry associations; and
· occupational health and safety consultants.
Consider external sources of information on dangerous occurrences, such as:
· manufacturers or suppliers of the dangerous goods or equipment;
· fire services; and
· published literature.
You may wish to include a requirement in all supply contracts that your suppliers identify all
known hazards associated with the containers and accessories used to store the dangerous
goods, any spill containment used, plant and the fire protection system.
Review information about dangerous goods
To identify hazards effectively, you must look at how the dangerous goods are stored and
handled. Therefore, when reviewing the information about dangerous goods, you should
consider the following factors:
10 The ADG Code has information about the relative hazards of Classes, and Subsidiary Risks and the
characteristics of Packing Groups.
11 Package labels provide some information about the hazards associated with dangerous goods. Some
products – for example, dangerous goods in consumer packages - may have sufficient information on the
consumer package label to cover most likely situations of handling, such as the clean up and proper
disposal of spills.
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(a) The inherent hazards of the dangerous goods, for example:
· fire;
· explosion;
· toxic effects
- inhalation;
- ingestion (swallowing contaminated food or eating or smoking with contaminated
hands);
- absorption through the skin or eyes; or
- corrosive action.
(b) The form (including concentration) in which the dangerous goods may be present, such
as solid, liquid or gas; supplied as packaged dangerous goods or in bulk. For example,
some goods may be virtually harmless in some forms (such as a block of metal) but may
become very hazardous dangerous goods in another form (such as a fine dust that can be
readily ignited or may be highly reactive).
(c) The chemical and physical properties. For example, gases or liquids with low boiling
points or high vapour pressures can give rise to high airborne concentrations in most
circumstances, whereas high boiling point liquids such as oils are only likely to create
an explosive airborne concentration if they are heated or sprayed. Dangerous goods with
a very low or high pH (ie. acids and caustics respectively) are corrosive to the skin and
eyes and corrosive to metals. Some dangerous goods are chemically unstable or highly
reactive (for example, many organic peroxides) and may self-react or react with other
materials to cause a fire or explosion. This information may include:
· physical state – solid / liquid / gas;
– if solid – what potential for dust cloud explosion?
– if liquid – mobile / viscous / volatile / miscible?
– if gas – lighter / heavier than air?
· flashpoint, firepoint and explosive limits;
· viscosity;
· density;
· particle size;
· vapour pressure;
· solubility and pH;
· reactivity;
· boiling and/or freezing point or range;
· electrical and/or heat conductivity; and
· the nature and concentration of combustion products.
(d) The types of incidents. For example, a Class 3 (flammable) dangerous goods may have
a very low flashpoint of – 5oC (that is, they are highly volatile) and under most ambient
conditions would able to ignite (within its explosive limits) when exposed to the
atmosphere. A high flashpoint product with a flashpoint of 56oC cannot be ignited
easily at ambient temperatures. The volatility of the dangerous goods will also affect the
likely intensity of any fire. Other characteristics like the mobility of a liquid (ie whether
it is thick like honey or thin like water) will determine how far a spill would spread and
in turn affect the spread of a fire.
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How factors can vary for different dangerous goods – petrol and caustic soda
Petrol and sodium hydroxide (caustic soda) are both dangerous goods, yet each has very different properties
that make them dangerous.
Petrol is dangerous principally because it is flammable, so the identification of hazards and the assessment of
risk should be based on the potential for fire and explosion. Petrol has other properties that may result in risk.
It can act as a solvent and dissolve other hydrocarbons like greases, and can dissolve or weaken certain types
of plastics. The assessment of risk should include whether there is potential to affect the operation of any plant
or weaken plastic structures through contact with petrol.
In contrast, even brief exposures to high concentrations of sodium hydroxide may lead to immediate effects
which include irritation or burning of the skin, eyes and respiratory tract. Sodium hydroxide is also corrosive
to metals and may react with other substances, particularly dangerous goods that are acidic. Evaluation of
risks for sodium hydroxide must therefore consider the potential for risk through a range of different
pathways.
How are the dangerous goods stored and handled?
Once you have identified the dangerous goods on your premises and reviewed the available
information you need to consider if the way the goods are stored and handled creates a hazard.
You must identify any hazards arising from:
Manufacturing and transport processes
· Are there any hazardous chemical and physical effects that may arise during the
manufacturing or transport process?
· Are procedures and operating parameters being adhered to?
An example of the need to determine and adhere to safe operating parameters is where a liquefied gas is being
pumped. A reduction in pressure on the suction side of the pump may result in the gas partially vaporising
before it enters the pump and causing a vapour lock within the pump. As a result, the pump stops pumping
liquid and instead recirculates a pocket of vapour that may cause the pump to overheat and fail
catastrophically unless safety controls have been specifically provided to detect such a condition and shut the
pump down before a failure occurs.
Structures, plant and system of work
Hazard identification for structures, equipment, systems of work and activities used in the
storage and handling of dangerous goods primarily involves the identification of all:
· physical components or characteristics which have the potential to cause harm;
· systems of work, including normal operating procedures and unusual operating conditions,
which could give rise to harm or damage;
· the possibility of operator error; and
· activities which may pose a threat to the dangerous goods.
It is important to observe and consult with employees to find out how the job is actually done.
People do not always work ‘by the book’, and may devise their own methods of work. Also,
find out what happens during cleaning, maintenance and breakdowns, and during staff
absences or shortages. Where you identify a difference between the way the system of work is
set out and the way it is implemented you should examine the reasons for the difference.
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Structures, plant, system of work and activities not used in the storage and handling of
dangerous goods
Some activities, systems of work, structures and equipment that are not directly involved with
the storage and handling of dangerous goods may constitute a hazard to the storage and
handling of the dangerous goods. An example of an external fire hazard could be the
development of a timber yard adjacent to the premises. Depending on the proximity of the
timber yard and stacks of timber to where the dangerous goods are stored and handled, a fire
at the timber yard could result in the dangerous goods becoming involved.
Consider the following hazard sources:
· Are there any dangerous goods stored near your premises?
· Do any of these activities on the premises occur?
- operation of plant;
- movement of vehicles;
- deliveries of dangerous goods;
- personnel movements in normal and emergency situations;
- visitor access;
· Are there any fire hazards, including concentrations of combustible material (for example,
a timber store or a store of C2 combustible liquids12) or uncontrolled vegetation on or off
the premises?
· Are there any activities and installations on neighbouring premises that could create a
hazard?
· What is the effect of a main road, railway line, airport, gas pipeline, water main, high
voltage power lines and radio transmitters including mobile phone repeater towers?
· Could nearby facilities such as schools, hospitals, child and aged care facilities, theatres,
shopping centres and residences be affected?
Chemical and physical reaction between dangerous goods and other substances and
articles
Physical reactions include dilution, dissolution, abrasion, phase change, leaching and
adsorption. Chemical reactions are reactions that result in a chemical change in one or more
of the goods when they come into contact with one another.
Consider:
· Is there a hazard as a result of a physical reaction from incompatible substances coming
into contact, for example, explosion or heat rapidly generated from acid mixing with
water?
· Is there a hazard as a result of a chemical reaction from different substances coming into
contact, for example, an oxidising agent such as pool chlorine mixing with a hydrocarbon
such as oil or brake fluid?
A list of the chemical and physical properties to be considered when identifying hazards
associated with the storage and handling of dangerous goods is at Appendix 5.
12 A definition of C2 Combustible liquids is in AS 1940
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Physical reaction
An example of a hazard arising from dilution is the mixing of acid and water. The addition of a small amount
of a concentrated acid to a large quantity of water may result in some heat being generated through the
dilution of the acid in the water but no hazard since the heat generated during dilution is quickly dissipated in
the water. On the other hand, the addition of a small amount of water to a large quantity of concentrated acid
may result in rapid boiling of the water as it dilutes the acid. If the heat generated can’t dissipate quickly
enough, the effect may be explosive. The hazard is the potential for hot acid to be splashed around.
Chemical reaction
The combination of an oxidising agent (pool chlorine) and a hydrocarbon (oil, brake fluid) can result in a very
intense fire that is difficult to extinguish. Not all chemical reactions will be hazardous – for example, the
combination of a weak acid and a weak alkali will result in a neutralisation reaction that is relatively nonhazardous.
However, the combination of concentrated solutions of the same products may result in a violent
reaction that can be explosive or generate a great deal of heat and may result in hot acid and alkali being
splashed around.
Type and characteristics of incidents
Incident information contributes to the state of knowledge of the dangerous goods and their
storage and handling. Consider:
· What types of incidents have occurred when storing or handling dangerous goods at your
premises?
· What is known about how these incidents were caused?
· What information is available about the effectiveness of risk controls and about how risk
controls can be improved?
· Have you taken into account incidents that have occurred at your premises and other
facilities storing and handling similar types of dangerous goods?
Step 3 – Risk assessment
The final step in the risk management process is to assess the risks associated with the
hazards. Risk assessment determines whether there is a risk of injury to people or damage to
property from the storage and handling of dangerous goods at the premises. The purpose of
the risk assessment is to:
· determine those risks that need to be controlled; and
· assist you to make decisions about the order in which risks should be controlled.
When carrying out a risk assessment, the Regulations require you to take account of the
information and knowledge gained about the dangerous goods and the matters that affect
safety in relation to the storage and handling of those goods.
Make sure that health and safety representatives are consulted at all stages of the risk
assessment process.
There are a number of methods for carrying out a risk assessment. At premises where
complex dangerous goods processes are involved, for example, chemical manufacturing
processes, it may be more effective to use a more highly structured process such a Hazard and
Operability Studies (HAZOP) or Hazard Analysis (HAZAN) to guide the hazard
identification and risk assessment process. In some situations it may be necessary to
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undertake quantitative risk analysis (QRA) to assist in the understanding of the extent of the
risks involved. More information about risk assessment is available in AS/NZS 4360.
What are the consequences of an incident?
In assessing the consequences of an incident, consider the potential:
· injuries and illness to people and property damage at the premises;
· for ‘knock on effects’ involving other dangerous goods at the premises;
· for injuries and illness to people and property damage outside the premises.
Assessing consequence: escape of volatile flammable liquid
A flash fire hazard has been identified with an escape of a large amount of volatile flammable liquid into the
spillage catchment area of a large bulk storage tank. Calculations show that a vapour cloud from the spill may
travel over a hundred metres from the catchment area before the concentration is reduced below the point at
which the vapour can be ignited (the lower flammable limit). The consequence of the ignition of the large
vapour cloud is that anyone inside the flammable portion of the cloud will be severely injured and it is likely
that any flammable material or construction will be ignited.
If the flammable portion of the vapour cloud could travel beyond the property boundary, the potential injury
and property damage outside needs to be determined.
If there is a labour-intensive manufacturing business within the potential envelope of the flammable vapour
from the spill, many people may be injured or even killed.
What is the likelihood that the hazard will result in an incident?
The next step is to estimate the likelihood that the hazard may cause an incident.
Look at historical records and review incident information from the premises and from similar
types of industries. People who work at the premises are a very useful source of information.
If the particular storage and handling operation is complex or is very high risk, a Quantified
Risk Assessment (QRA) may be needed.
Estimating likelihood: example
An explosion hazard has been identified in relation to the welding of drums that once contained flammable
and combustible liquid. The consequences of an explosion involving the tank are severe because it is likely to
cause the death of the person doing the welding.
The person carrying out the risk assessment talks to management and supervisors to find out how often drums
are welded. The health and safety representative and workers are also consulted about the hazard. The
combined history of those involved shows that welding of drums has happened very infrequently and no one
knows whether the drums contained flammable or combustible material.
The risk assessment concludes that the welding operation is likely to cause an incident. It has happened and is
likely to happen again if steps are not taken.
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17.2 Generic risk assessment
Often, particular dangerous goods are used in the same or similar way in a number of different
premises, or in areas within the same premises. Because the nature of the hazard and the risk
in these cases may be similar, you are permitted to make a single assessment of one
representative situation and apply it to the other areas or premises. By performing generic
assessments, you can minimise the duplication of assessments, thereby streamlining the risk
assessment process. As with risk assessments generally, you must consult with employees and
health and safety representatives and any other people you have engaged at the premises,
when carrying out generic risk assessments.
You are responsible for ensuring that the generic assessment is valid for each of the premises
or areas to which it is intended to apply. A generic assessment is valid if both the dangerous
goods and their storage and handling are essentially similar. For example, a factory
repackages Class 3 dangerous goods and has four separate packaging lines that are the same
and are able to repackage the same range of products. The hazard identification and
subsequent risk assessment needs only to be done on one of the packaging lines and applied to
the other three. Similarly, if a generic assessment is undertaken by a trade association as a
model to be used by a number of different occupiers with essentially identical premises – for
example, service stations and retailers – the individual occupier is responsible for ensuring
that the assessment is valid for his or her own workplace. An example of an Australian
Standard that can be used in this generic way is AS 1596 – Storage and handling of LP Gas.
This Code refers to a range of Australian Standards and specific industry publications. In
many instances the risk controls identified in those documents have been formulated
following analysis of particular hazards and their risks. You may rely on the generic
assessments when the control measures stated in the documents are implemented and directly
applicable to the storage and handling situation to which they are applied. In those
circumstances you should identify the hazards being controlled and refer to the Standard
being relied on for the generic assessment.
If the situations are not similar and employees in different premises or areas of the same
premises may be subjected to different risks, a generic risk assessment cannot be performed or
may need to be supplemented to address those different risks.
17.3 Recording the outcomes of risk assessments
Outcomes of risk assessments must always be documented. Risk assessment records should
include:
· name(s) of the assessor(s);
· date of the assessment;
· the premises/area/process;
· the dangerous goods for which the MSDS or equivalent information has been reviewed;
· the controls in place to prevent a risk;
· the nature of risk identified; and
· why decisions about the risk were made.
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The record of the result of the assessment must be accessible to any person engaged to work
at the premises who could be exposed to a risk, and their health and safety representatives.
An extensive record of the assessment is not required if you have identified that the storage
and handling of the dangerous goods does not result in a risk that needs to be controlled.
A record of the risk assessment should be of assistance when undertaking any subsequent risk
assessments that may be necessary because of changes to the dangerous goods used, systems
of work, plant, structures or other circumstances that could result in change to the risk profile
of the premises.
17.4 Reviewing and revising risk assessments
A risk assessment may no longer adequately assesses the risk associated with the storage and
handling of particular dangerous goods. In this case, the risk assessment must be reviewed
and, if necessary, revised. The assessment needs to be revised if:
· a new dangerous goods is introduced into the premises;
· the process or plant is modified;
· new information on the hazards of the dangerous goods becomes available;
· monitoring indicates inadequate risk control;
· incidents or near misses have occurred which may be due to inadequate control; or
· new or improved control measures become available or practicable.
Where it is known that circumstances will change, you may be able to prepare a risk
assessment that takes the projected or known changes into account. In this way, you can
ensure that the assessment will continue to deal with the risk adequately after the changes take
place.
In any case, a risk assessment must be reviewed at intervals not exceeding five years. If the
assessment remains correct (that is, it adequately assesses the risk), simply record the date of
review.
18. Risk control
18.1 What is risk control?
Risk control is the process of determining and implementing appropriate measures to control
the risks associated with the storage and handling of dangerous goods.
When planning and implementing risk control measures you must consult with your
employees and any other people you engage to carry out work at your premises that are likely
to be affected by the dangerous goods.
18.2 What does ‘practicable’ mean?
“Practicable” does not just mean the cost in dollar terms. To determine what is practicable,
you, as a duty holder, must take into account:
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(a) severity of the hazard or risk in question
How likely is it that the storage and handling of the dangerous goods will result in
injury to people or the likelihood of damage occurring to property? How serious are the
injuries and property damage likely to be and how many people could be affected?
(b) state of knowledge about that hazard or risk and any ways of removing or
mitigating that hazard or risk
What is known about the hazards or risks associated with the storage and handling of
the dangerous goods, and the ways to control the risk? What do manufacturers and
suppliers of dangerous goods know about the hazards and risks? What do workplaces
dealing with similar dangerous goods do to control the risk? What information can
industry professionals and organisation, unions and government agencies provide?
(c) availability and suitability of ways to remove or mitigate that hazard or risk
Are the risk controls that you have identified readily available? Are they suitable for the
premises and the employees involved?
(d) cost of removing or mitigating that hazard or risk
Are the costs of implementing the risk control commensurate with the benefits gained?
Time and money invested in selecting and implementing risk controls should result in
the elimination or significant reduction in risks from using dangerous goods.
18.3 The duty to control risk
You have a duty to ensure that any risk associated with the storage and handling of dangerous
goods at your premises is controlled. The primary duty is to eliminate the risk. If this is not
practicable, the risk must be reduced so far as is practicable.
The Regulations also place some specific duties on you to control risks associated with
particular aspects of storage and handling of dangerous goods. Giving effect to these specific
duties does not displace your general obligation to control risk. Figure 4 summarises the
duties of occupiers to control risks.
The Australian Standards and other documents that are listed in Appendix 3 provide specific
guidance on risk controls that can be applied to address specific hazards associated with the
storage and handling of dangerous goods. The duty to control risks can be met for many
identified risks by applying the risk controls that are specified in those documents. The use of
the risk controls is subject to the conditions of storage and handling at the premises being the
same or sufficiently similar that the specific and generic controls in the documents are
applicable to those situations. In many instances the documents will provide specific risk
controls that are able to address many of the risk control duties in the Regulations.
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Figure 4: Summary of occupiers duties to control risks in regulations 407-425
General risk control
duties Specific risk control duties
Control the risk
r.407
Eliminate use
Substitution
Engineering
Isolation
Administrative
PPE
r.411
Interaction with
substances and
unrelated plant
r.416/7
Bulk containers
r.419
Isolation
r.415
Stability
r.414
Decommissioned
containers r.420
Ignition sources
r.424
Spill containment
r.422