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Hydrofluoric Acid - Guidelines for safer
handling and storage
Introduction
This guidance note provides information for anyone who
uses hydrofluoric acid or is responsible for managing or
supervising its use in the workplace.
Hydrofluoric acid is a solution of hydrogen
fluoride in water. It is corrosive, and highly poisonous. Skin
contact with concentrated hydrofluoric acid or inhalation of
its vapour has caused many serious injuries, even death.
Concentrated solutions of hydrofluoric acid pass quickly
through the skin and cause deep, painful burns. Dilute
solutions also penetrate the skin, but it does not give the
immediate burning sensation caused by the concentrated form of
the acid, a user may tend to be less aware of the contact with
the acid.
Hydrofluoric
acid is used in many industries including metal
treatment/cleaning, car detailing, glass etching, brick
cleaning and laundry/dry cleaning.
Health effects
Hydrofluoric acid can cause serious injury
or illness by:
- Skin contact:
Concentrated
hydrofluoric acid in contact with the skin will penetrate
the skin to damage deeper tissues. This can lead to
full-thickness skin burns. As well as this, fluoride
entering the bloodstream will trap calcium and magnesium
ions with rapid harmful effects on the heart, muscles and
nervous system. Because of this, skin absorption is the main
route of exposure for fatalities. Even dilute solutions will
penetrate the skin although the effect is usually delayed.
Once the dilute solution has penetrated, its destructive
action will continue even after surface solution has been
washed off.
- Eye
exposure: A splash of
hydrofluoric acid into the eyes can rapidly and permanently
damage sight and urgent eye irrigation is required followed
by immediate medical advice.
- Inhalation: The vapour of hydrogen fluoride, when
inhaled, is almost completely absorbed into the bloodstream
from the nose, throat and upper airway, before it reaches
the lungs. During absorption, it can irritate or cause
symptoms as mild as itching of the nose. However, inhalation
of high concentrations of hydrogen fluoride vapour is very
irritating and its absorption into the blood stream can be
fatal in the same way as skin absorption.
- Ingestion: Hydrofluoric acid can cause severe
mouth, throat and stomach burns and may be fatal if
swallowed.
NOTE: Do not
confuse hydrochloric acid with
hydrofluoric acid because
of the similarity of names. On the skin, hydrochloric
acid burns from the outside in. Hydrofluoric acid
solution readily penetrates the skin and burns both skin
and deeper tissues. If enough acid is absorbed, it may
affect the heart and nervous
system. | Legal requirements
Under the Victorian Occupational Health & Safety (Hazardous
Substances) Regulations 1999 employers have a legal obligation to protect people at
work against risks to their health associated with the use of
hazardous substances. Work involving the use of products
containing hydrofluoric acid at a concentration of 0.1% or
higher falls within the scope of these Regulations. Solutions containing concentrations
greater than 0.1% hydrogen fluoride are also Schedule 6 or
Schedule 7 poisons. In Victoria, a permit is required from the
Department of Human Services to sell or supply hydrofluoric
acid.
Hydrofluoric acid
is also classified as a Dangerous Good (refer Australian
Dangerous Goods Code); it has a primary risk of Class 8
(corrosive) and a subsidiary risk of Class 6.1 (toxic). The
Dangerous Goods (Storage
and Handling) Regulations 2000 set out the requirements for the safe handling and
storage of hydrofluoric acid.
Before using hydrofluoric acid for a work process,
employers are required to obtain and have readily available a
copy of the material safety data sheet (MSDS) from the
manufacturer, importer or supplier. The MSDS provides
information about the hazards of hydrofluoric acid and how to
use it safely.
Preventing the risk of exposure
- Consider whether the process
that uses hydrofluoric acid needs to continue.
- Consider whether a substance
less hazardous than hydrofluoric acid will do the job
instead.
- If a substitute is not
available, then use the most dilute solution of hydrofluoric
acid that is effective.
Controlling the risk of exposure
- Purchase hydrofluoric acid in
ready to use concentrations rather than handling the
concentrated hydrofluoric acid and diluting it
yourself.
- Work with hydrofluoric acid in
a well-ventilated area when the process that involves its
use cannot be enclosed or controlled using local exhaust
ventilation.
- Always wear personal protective
equipment when handling hydrofluoric acid (see also the
Personal protective
equipment section
below).
- Use sealed equipment such as a
self-priming siphon or pump when transferring concentrated
hydrofluoric acid.
- Use spouts and pourers designed
to reduce flow when diluting hydrofluoric acid. Prefer
containers from manufacturers that supply these.
- Make sure that the
tanks/containers of hydrofluoric acid have fitted lids or
caps.
- If you need to dilute
hydrofluoric acid, always add the acid to water,
never the water to acid.
- Do not work alone when handling
hydrofluoric acid of more than 10 per cent
concentration.
- Even when using dilute
hydrofluoric acid wash hands and gloves in water
frequently.
- Rinse components that have come
into contact with hydrofluoric acid extremely well to avoid
injuring other people who touch them after you.
- Use a brush or roller to apply
hydrofluoric acid rather than a spray application.
- Develop and document safe work
and emergency procedures covering control, first aid, spill
containment and disposal of contaminated
material
Information and Training
- Obtain a material safety data
sheet from the supplier and follow the
recommendations.
- Transfer the dilute
hydrofluoric acid into properly labelled containers. This is
important because dilute hydrofluoric acid solution has the
same appearance as water.
- Be thoroughly aware of the
hazards and fully trained in the safe use of hydrofluoric
acid, its first aid and emergency
procedures.
Personal protective equipment
(PPE)
Always use
suitable personal protective equipment (PPE) and clothing to
protect your skin, face, eyes, etc from exposure to
hydrofluoric acid. Recommended equipment and clothing
includes:
- a full face plastic shield
and/or safety glasses
- gloves that are resistant to
hydrofluoric acid such as nitrile or natural rubber
- long sleeved protective
overalls
- protective boots, such as
rubber boots
- protective apron (covering top
of boots) when handling concentrated hydrofluoric
acid
- approved respirator (complying
with AS/NZS 1716) fitted with an acid-gas filter, when
working in confined areas or when it is necessary to spray a
solution of hydrofluoric acid.
NOTE: Workers
using PPE must be trained in its proper use and
limitations. | Clean up after using hydrofluoric
acid
Ensure that
PPE is thoroughly cleaned with water after its use and checked
for any damage, for example pinholes or cuts in the gloves,
especially the fingertips. Professionally launder all
contaminated clothing. Following any contamination of clothing
with hydrofluoric acid, remove the garments at once and place
them in a large volume of water such as in a trough.
Preferably, make the water mildly alkaline – for example, add
a heaped tablespoonful of sodium bicarbonate (baking soda).
Clothing, heavily contaminated with hydrofluoric acid, should
be decontaminated (as above) and then be
disposed.
Always store
cleaned PPE in clean, dry conditions, preferably a
locker.
Wash hands and
faces at the end of each job, and before eating, drinking,
smoking or going to the toilet. Where possible, arrange for
users of hydrofluoric acid to shower before leaving
work.
First Aid and
medical
Where
hydrofluoric acid is handled, always have calcium gluconate
gel antidote available. Ensure that First Aiders, hospitals
and clinics in the area are informed and equipped to treat
hydrofluoric acid exposure. Provide safety showers and eyewash
stations, and any additional equipment recommended in the
First Aid section of the MSDS.
Calcium gluconate gel should be stored below 25 degrees
Celsius to remain efficient. The gel has a limited shelf life
and must be discarded and replaced after expiry. Calcium
gluconate gel and tablets are available from selected
pharmacies or distributors of first aid medical
supplies.
Appropriate
emergency procedures and treatment must start immediately following any accidental exposure to hydrofluoric
acid. Refer to the material safety data sheet from the
manufacturer, importer or supplier.
Storage
Hydrofluoric acid must be kept in its original package
and stored in a ventilated, cool and dry area and out of
direct sunlight. In enclosed storage areas, hydrofluoric acid
vapour may cause serious corrosion of sprinkler
systems.
Store
hydrofluoric acid close to ground level, on corrosion
resistant surfaces, and in well-marked areas so it cannot be
confused with other acids like hydrochloric acid. The area
should be accessible enough to avoid excessive handling, and
have spill retention measures so that any spill of
hydrofluoric acid is contained. If spill and leaks of
hydrofluoric acid occur, they must be immediately cleaned up
according to the directions in the MSDS.
Keep hydrofluoric acid well separated from
other acids, alkalies, flammable liquids, pool chlorine, and
solvents. Do not mix with other chemicals – this may result in
fire and chemical reactions or explosion. Promptly dispose of
any redundant stock of hydrofluoric
acid.
Further
information
Acts, Regulations &
Codes
Occupational Health and
Safety Act 1985 Occupational Health and Safety (Hazardous
Substances) Regulations 1999 Dangerous Goods (Storage and Handling) Regulations
2000 Australian Code
for the Transport of Dangerous Goods by Road and Rail
(also known as the Australian Dangerous Goods
Code) Acts and
regulations are available from Information Victoria on 1300
366 356 or order online at www.bookshop.vic.gov.au/
If you only
want to view the legislation you can use the Parliament of
Victoria web site; go to www.dms.dpc.vic.gov.au/ , click on
"Victorian Law Today" and scroll down to the "Search"
window.
WorkSafe Victoria
Code of Practice for
Hazardous Substances – June 2000 Copies of publications, including codes of
practice, can be obtained by contacting WorkSafe Victoria on
03 9641 1555, or your local WorkSafe Victoria
office.
Other useful
health and safety information is available on WorkSafe
Victoria's web site; go to www.workcover.vic.gov.au and
click on the WorkSafe Victoria logo.
Australian
Standards
AS/NZS 1716 – 2003: Respiratory
protective devices Copies of standards can be obtained by contacting
Standards Australia on 1300 654 646 or by visiting the web
site at www.standards.com.au.
Other
National Industrial Chemicals
Notification and Assessment Scheme
(NICNAS) Hydrofluoric Acid (HF) – Priority Existing Chemical
Assessment Report No. 19, June 2001 NICNAS falls under the jurisdiction of the Australian
Government Department of Health and Aging. To view this
document go to the NICNAS web site, www.nicnas.gov.au , then select Publications,
Chemical Assessment
Reports, Priority Existing Chemicals Assessment
Reports, and scroll down
to PEC/19. Alternatively, insert the following
address into the internet address field: www.nicnas.gov.au/publications/CAR/PEC/PEC19/PEC19index.htm
National Occupational Health
and Safety Commission (NOHSC) The NOHSC web site provides access to
technical data and occupational health and safety information;
go to www.nohsc.gov.au/OHSLegalObligations/ If you
can't find guidance material that gives the solutions or
advice you're after, try the national database of guidance
material on the NOHSC web page; go to natindex.nohsc.gov.au/
Suppliers of hydrofluoric
acid Suppliers
are a good source of
information on use, chemical properties and health effects of
this substance.
Note: This guidance material has been prepared using the best
information available to WorkSafe Victoria. Any information
about legislative obligations or responsibilities included in
this material is only applicable to the circumstances
described in the material. You should always check the
legislation referred to in this material and make your own
judgement about what action you may need to take to ensure you
have complied with the law. Accordingly, the Victorian
WorkCover Authority extends no warranties as to the
suitability of the information for your specific
circumstances.
GN 02/2004February |
This
document may be freely copied or reprinted. |
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