TRP 2
Handling of Acids and Bases
IAMC Toolkit
Innovative Approaches for the Sound
Management of Chemicals and Chemical Waste
Toolkit/CSD&ISSPPRO 2
Acid and bases are widely used in the chemical industry. This presentation provides explanation of the harm that acids and bases can have on human beings and on the environment.
The principle of substitution is explained to the reader, as well as the technical and organizational measures to implement to reduce the exposure to these substances.
Introduction
1. Risk identification
and safety
2. Transport and
storage
3. Fire and explosion
protection
4. Emergency
response
11. Chemical classification
and labelling
21. Internal transport of
chemicals 31. Fire protection
41. Emergency response
plan
12. Risk assessment 22. Internal pedestrian
routes
32. Fire protection in
welding and cutting
operations
13. Safety rules 23. Storage 33. Explosion protection
14. Personal protective
equipment 34. Container cleaning
15. Skin protection
16. Emergency escape
routes
17. Handling of solvents,
acids and bases
18. Safety in gas tank
handling
Hazard Management
Checklists
4
1. General Concepts
Acids and bases
2. Hazards
3. Prevention Measures
Substitution
Technical measures
Organizational measures
4. Sources
Contents
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General Concepts
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Acids and Bases
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Acids Bases
pH
Hyd
roch
loric a
cid
32
-34
%
Su
lph
uric a
cid
95
-98
%
Sa
licylic
acid
(asp
irin
)
Cau
stic s
od
a 9
9%
Cau
stic s
od
a 5
-45
%
Am
mo
nia
so
lution
10
-35
%
Wate
r
Source: CSD
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The pH value distinghuishes substances according to their acid or basic behavior.
Hazards
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Main Hazards
The main hazards associated with the use, storage and transport of acids and bases are:
Environmental hazards (e.g. water pollution,
death of aquatic life, etc.)
Health hazards:
The majority of acids and bases can cause irritations, burns or intoxications if not adequately used.
Routes of entry of the substances:
Inhalation of the vapours
Skin permeation
Ingestion
Consequences:
Irritations
Chemical burns, etc.
Inhalation
Skin
permeation
Source: Suva
Ingestion
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Prevention Measures Technical Measures
Organizational Measures
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Prevention Measures
Prevention measures
follow the STOP logic:
S. Substitution of the
hazardous substances
and processes
T. Technical measures
O. Organizational
measures
P. Personal protection
measures
Source: Suva
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Substitution
Substitution aims at reducing the risks of health and
environmental hazards. Attention: It is not acceptable to replace a carcinogenic substance by a less
harmful but highly flammable substance.
A thorough risk analysis has to be conducted prior to
introducing any new substances or processes.
Substitution example: Replace highly dosed caustic soda (30%)
by a less highly concentrated caustic soda solution (10%).
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Substitution – Example
Coffee powder manufacturing plant – Initial situation
Acid effluent
(Coffee residues)
Pre-treatment
plant
Neutralized effluent Sewage
system
Caustic soda (NaOH)
Production: normal situation
Caustic effluent
(NaOH residues)
Pre-treatment
plant
Neutralized effluent Sewage
system
Hydrochloric acid (HCl)
Cleaning: every 3 days Source: CSD
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Substitution – Example
Coffee powder manufacturing plant – Optimized situation
Caustic effluent
(NaOH residues)
Caustic effluent
storage
Cleaning: every 3 days
Acid effluent
(Coffee residues)
Pre-treatment
plant
Neutralized effluent Sewage
system
Production: normal situation
- NaOH substituted with
caustic acid effluent
- HCl substituted with acid
effluent
Source: CSD
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Technical Measures
Installations, containers and tanks
Any part of an installation, container or tank likely to be in
contact with acids or bases needs to be:
Conceived with a material that does not react with the
substances
Resistant to the induced stress and solicitations.
Tanks should be equipped with an air vent and devices to measure
the content level (to avoid overflowing).
The fittings used for filling the tanks should be marked to avoid
dangerous confusions (label, unique colour assigned per substance,
etc.).
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Technical Measures
Pipes
Piping used to carry acids and bases should be clearly
labelled, unobstructed, easily accessible and if necessary
protected against the risk of mechanical deterioration.
Each pipe carrying acids and bases should be equipped
with an emergency shut-off valve.
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Technical Measures
Ventilation of the workplaces:
Natural ventilation (windows, doors, openings)
Artificial ventilation (general ventilation, ventilation at source )
Evacuated vapours are usually filtered or washed and then either
discharged to the atmosphere or fed back into the room.
Artificial ventilation
Source: Suva
Ventilation is essential in zones
where acids and bases
produce vapours, fumes and
mists.
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Technical Measures
Ventilation at source – Examples:
Ventilated open cabin
Source: INRS
Laterally ventilated oil extraction tanks
Source: INRS
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Technical Measures
Ventilation of storage premises:
Natural ventilation (windows, doors, openings)
Artificial ventilation (general ventilation) Evacuated vapours are usually filtered and then either discharged to the atmosphere or fed back
into the room.
Natural ventilation Artificial ventilation
Source: Suva Source: Suva
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Technical Measures
Storage of acids and bases:
Storage premises containing acids or
bases should be locked.
Containment measures should be
taken to prevent liquids from
spreading, including:
Safety sills
Retention basins
Retention basins should be built with
a material that does not react with the
stored substances.
Source: Suva
Caution: Retention basins
should be built with a suitable
material
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Technical Measures
Storage of acids and bases:
Incompatible substances must not be stored together.
They must never share the same retention basin.
Do not store together:
- Acids and bases
- Acids and cyanides
- Acids and sodium hypochlorite
- Acids and sulphides, hydrogen sulphides
- Acids and alkali metals
- Nitric acid and hydrochloric acid
- Nitric acid and flammable solvents
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Technical Measures
Storage cabinets:
In working areas, only the
quantities required for the good
functioning of the operations
should be stored.
Storage must be equipped with a
collecting vessel and adequately
labelled cabinets.
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Source : Suva
Technical Measures
Extinguishers and first aid:
Areas where acids and bases are handled
have to be equipped with:
First aid facilities (showers, eye-wash
stations)
Absorbent material in case of spills/leakage
These facilities have to be regularly
checked.
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Source: Shutterstock
23
Technical Measures – Recap
Substitution of hazardous substances
Ventilation of workplaces and storage premises
Storage of acids and bases (retention basins, safety sills,
storage cabinets)
First aid facilities
Natural ventilation Artificial ventilation
Source: Suva Source: Suva
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Prevention Measures Technical Measures
Organizational Measures
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Safety Data Sheets (SDSs)
The safety data sheets (SDSs) include the following useful information:
Physical data (melting point, boiling point, flash point, etc.)
Toxicity
Health effects
First aid
Reactivity
Storage
Disposal
Protective equipment
Spill-handling procedures
SDSs provide workers with information and procedures to safely handle and work with
chemical substances.
For each chemical substance, an SDS must be registered and easily available. A good
practice would be to store the SDSs with the concerned substances.
Source: CSD
D11_Chemical classification and labelling
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Safety Data Sheets (SDSs)
An SDS comprises 16 categories of information
1. Identification 2. Hazard(s)
identification
3. Composition/
Information on
ingredients
4. First-aid
measures
5. Fire-fighting
measures
7. Handling and
storage
6. Accidental
release measures
8. Exposure
controls/personal
protection
Sections 1 to 8 contain general
information about the substance
9. Physical and
chemical properties
10. Stability and
reactivity
11. Toxicological
information
12. Ecological
Information
13. Disposal
considerations
15. Regulatory
information
14. Transport
information
16. Other
information
Sections 9 to 16 contain other technical and
scientific information about the substance
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Organizational Measures
Labelling containers, tanks, pipes, etc.
The equipment (containers, tanks, pipes, etc.) should be
appropriately labelled.
Labels should be permanent and easily visible.
Labels should use standard symbols.
HYDROCHLORIC
ACID
Source: CSD
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HYDROCHLORIC ACID
1
2
3
4
5
Precautionary statements Additional information as required by the competent authority as appropriate
Supplier identification
SIGNAL WORD
Hazard statements
Organizational Measures
Labelling containers, tanks, pipes, etc.
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Organizational Measures
Safety signs:
Zones where acids/bases are stored or handled should be
indicated by safety signs.
Zones where the use of
personal protective
equipment is mandatory
should be clearly indicated by
specific signs.
Corrosive substance
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Source: Suva
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Organizational Measures
Installations and equipment
Special devices used for the decanting
of acids and bases should be available
(e.g. pumps, etc.)
Safety containers and trolleys for
barrels should be available to transport
acids and bases.
Absorbents should be provided to
collect and eliminate spilled acids and
bases.
Manual pump
Source: Suva
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Organizational Measures
Staff training should:
Provide the knowledge employees need to work in safe conditions
Take place when they join the company and at regular intervals
Be extended to any staff of third-party companies working in hazard
areas
Include the following topics: Legal foundations and requirements
Labelling schemes used for chemical substances and mixtures
Main rules of conduct
Requirements for the personal protective equipment including monitoring,
maintenance, etc.
Good practices when working in explosion-hazard zones
First aid and fire protection guidelines
Guidelines for the sorting and disposal of waste, etc.
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Organizational Measures – Exercise
What should you do before handling
any unknown substance?
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Organizational Measures – Exercise (1)
Read the safety data sheet where you can find information
about:
Physical data
Toxicity
Health effects
First aid
Reactivity
Storage
Disposal
Protective equipment
Spill-handling procedures
Source: CSD
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Risk Reduction Measures Personal Protective Equipment
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Personal Protective Equipment (PPE)
To be used if the hazard could not
be totally eliminated by substitution
or technical measures.
The safety data sheets (SDS) of
the substances used should
indicate any relevant information to
ensure their safe handling.
Management should ensure that:
Staff is well trained
Protective equipment is regularly
checked
Staff complies PPE guidelines
Zones where PPE is
required should be clearly
indicated.
Source: Suva
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Types of PPE
Eye and face protection is essential
when handling acids and bases.
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Source: Suva
Source: Suva
37
Personal Protective Equipment (PPE)
Respiratory
protective
equipment
Skin protective
equipment
Protective
eyewear
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Key messages
The main hazards associated with the use, storage and
transport of acids and bases are environmental hazards
and health hazards.
Substitution aims at reducing the risks of health and
environmental hazards.
A thorough risk analysis has to be conducted prior to
introducing any new substances or processes.
Planned prevention measures can be technical or
organizational.
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Sources
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Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet magna eros quis (ARIAL 32).
Sources
CSD Engineers, Switzerland/ISSPPRO, Germany, 2015
Confédération Suisse: Directive CFST n°6501 – Acides et bases,
Switzerland, 1990
Suva: Liste de contrôle: Acides et bases, Switzerland, 2012
United Nations: Globally Harmonized System of Classification and
Labelling of Chemicals (GHS), 2003
Sicherheitsinstitut: Lagerung gefährlicher Stoffe, Leitfaden für die
Praxis, Überarbeitete Auflage 2011, Switzerland, 2011
INRS: Postes d’utilisation manuelle de solvants, France, 2009
Waswo: www.extra.suva.ch, Switzerland, June 2015
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Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet magna eros quis (ARIAL 32).
Images
CSD Engineers, Switzerland, 2015
Suva: Pulvérisation au pistolet de vernis et peintures polyuréthane
comment protéger vos collaborateurs, Switzerland, 2012
Suva: Santé et sécurité au travail lors de l’emploi de solvants,
Switzerland, 2012
Suva: Liste de contrôle – Risques d’explosion, Switzerland, 2013
Suva: Liste de contrôle – Emploi de solvants, Switzerland, 2012
INRS: Postes d’utilisation manuelle de solvants, France, 2009
Shutterstock, USA, 2015
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This presentation was prepared with the requested diligence
and with the generally accepted principles of the relevant
field.
If a third party uses the contents of the presentation in order
to take decisions, the authors disclaim any liability for any
kind of direct or indirect (consequential) damage.
Disclaimer
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