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RhinoLite
A LIGHTWEIGHT BASECOAT AND FINISHING PLASTER
METHODS OF APPLICATION
RHINOLITE is a lightweight retarded hemihydrate
gypsum plaster, specially manufactured as a combined
basecoat and finishing plaster for internal application
onto brickwork, concrete block, concrete and
Rhinoboard, and as a finishing plaster onto sand cement
basecoats.
RHINOLITE two-in-one plaster is suitable for providing:
• a highly polished smooth surface,
• a brush finish, or
• a textured finish, and should be used neat, with the
addition of clean water only. The plaster has a
setting time of approximately 60 minutes.
As in good building practice, roof, windows and doors
should be installed before plastering with RHINOLITE. (To
help prevent dry-outs).
RHINOLITE should not be used in areas where walls are
washed with hosepipes, in showers or in industrial type
kitchens.
Basecoat and finishing plaster onto brickwork concrete and concrete blocks
Brush off loose cement with a wire brush. Check all dust
removed. Slight damping down will help settle dust. Fix
plaster corner beads, plumb and square on all external
corners and reveals using RhinoLite. Apply corner beads
before plastering.
MIXING
1. Do not add foreign matter (e.g. Cement) to RhinoLite.
2. Measure 22 litres water into a container.
3. Add 40kg RhinoLite slowly to clean water, allow to
soak for 5 mins.
4. Mechanical mixing is preferable for aeration and
workability.
5. Mix till lump free. Do not re-stir or add to mix after
mixing is complete.
6. Only mix as much RhinoLite as can be used in 60 mins.
No more than 2 x 40kg bags per mixing container.
7. Clean utensils between mixes. Remnants of previous
mix must not be added to fresh mix.
8. Do not apply RhinoLite if temperature below
freezing.
9. Before decoration check surface has set hard and is
dust-free.
NB Water ratio is approximate. Workability can be
altered by altering water volume.
ISSUE DATE: DECEMBER 2005
NB Plaster corner beads are strongly recommended but
RhinoLite corners can be finished with a corner tool.
Apply a thin coat of RhinoLite, follow with filler coat to
thickness required. Use feathered edge, straight edge or
darby to level out. Brush up and down evenly with a
damp block brush for a brush finish. For a smooth finish
stand till plaster stiffens then:
i) on areas plastered with same mix, float surface with
sponge rubber float to level area and bring ‘fat’ to surface. Hold steel trowel acute to wall and remove ‘fat’
while polishing the surface.
ii) On areas plastered with different mixes. Apply a tight
skim coat from one mix, cover surface and finish with a
rubber float and steel trowel.
Concrete
Grease or oil is always detrimental to the bond of plastering material. Therefore, scrub concrete surfaces with
cleansing agent to remove grease or oil. Rinse with copious amounts of water till entirely clean. Apply Grippon
plaster bonding liquid using a brush or roller. While still
wet and tacky, follow with application of RhinoLite as
previously described.
Basecoat and finishing plaster onto Rhinoboard
Tack 63mm wire scrim or apply 48mm RhinoTape over all
joints, apply double layer FibaTape over butt joints.
Apply RhinoLite to joints in all directions ensuring
RhinoLite pushed firmly into RhinoTape or wire scrim.
Allow RhinoLite to set (not dry) then plaster with 3-6mm
of RhinoLite. RhinoLite must be applied to Rhinoboard’s
unprinted side.
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RhinoLite
(not dry) then plaster the entire ceiling with 3-6mm of
RhinoLite. RhinoLite must be applied to the unprinted
side of RHINOBOARD.
Finishing plaster onto sand cement basecoats.
Use clean sharp sand for the basecoat in accordance
with SABS Specification No. 1090/1976.
A suitable basecoat can be made up of 4 parts plaster
sand, two parts river sand, and one part cement.
The sand cement basecoat must be COMPLETELY DRY
before RHINOLITE is applied. Brush down the entire surface to remove all loose particles. Wet the sand cement
basecoat to eliminate excessive suction.
RHINOLITE finishing plaster is applied in two layers, the
first of which should be a thin tight layer. The
second filling-out layer, to between 2 - 3 mm thick, follows immediately.
As the plaster stiffens, float and/or steel trowel to a
smooth surface free from blemishes, as described in
paragraph (a) and (b) in the base/finishing coat
application.
Application to painted surfaces
Ensure that the painted surface is sound and free of
bubbles, loose particles and/or oiliness. Apply
GRIPPON plaster bonding liquid in accordance with the
manufacturer’s instructions and whilst it is still wet and
tacky, follow with the required application of RHINOLITE plaster.
COVERING CAPACITY
The approximate coverage of a 40 kg bag of RHINOLITE is:
25 m2 applied to a thickness 2 - 3 mm
11,5 m2 applied to a thickness 5 - 6 mm
4,5 m2 applied to a thickness 12 - 15 mm
3 m2 applied to a thickness 15 - 20 mm
The approximate coverage of a 10 kg bag of RHINOLITE is:
2-3 mm
= 7 m2
5-6 mm
= 2,88 m2
12-15 mm
= 1,12 m2
15-20 mm
= 0,75 m2
NB: RHINOLITE should not be applied less than 2-3 mm
thick.
DECORATION
Before decorating check the entire surface carefully to
see that the plaster has set hard and is dry and free from
dust/powder. Under no circumstances should RHINOLITE
be sandpapered. All RHINOLITE surfaces must be sealed
with an oil based paint bonding liquid or a pigmented
plaster primer suitably thinned down with mineral turpentine. Allow to dry for 24 hours before applying two
coats of household paint.
NB: Epoxy paints not to be applied onto RHINOLITE.
RHINOLITE LIST OF BENEFITS
Superior smooth finish
•
Can be floated up to 1 hour after application.
Lightweight
•
Sand/cement weight +- 22 kg/m2 at 12 mm,
RhinoLite weighs +- 9 kg/m2. Results in less
effort/m2.
•
Reduction in transport costs to site.
•
Reduction in on-site labour, particularly in highrise (the weight to be moved around the site or up
to various floors has been halved).
•
Much more acceptable to artisans as it is easier and
lighter to work with.
•
Premixed in bags - just add water.
Speed
•
Can be applied much quicker, estimates at the
moment range from 25% to 50% faster than
sand/cement.
•
Unskilled labour reduced due to easier mixing of
product.
•
Overheads reduced because contracts completed
quicker.
•
Extra profits obtained because same number of
crews produce more work per annum.
•
The shortage of skilled plasterers becomes less of a
problem because of substantial increase in
productivity.
•
Sets and dries faster - you paint sooner.
Cleaner product
•
Easier to keep the site clean.
•
Better working conditions due to cleaner site.
•
Savings - less wastage.
•
Savings - less cleaning up.
•
Product (packed in 10 kg and 40 kg bags) gives
easier stock control.
Better performance
•
Less shrinkage cracks.
•
Better adhesion to lintels and concrete when used
with GRIPPON due to special adhesive in plaster.
•
Used as a base coat it eliminates the bond
problems sometimes obtained on 2 coat work due
to the shrinkage of fatty/poor quality sands.
•
Does not shatter or crack when nails are driven
into it.
Brickwork
RHINOLITE
Plaster angle Bead
Rhinoboard
Wire Scrim/RhinoTape
ISSUE DATE: DECEMBER 2005
RHINOLITE
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How to use RhinoLite
* RhinoLite training videos are available.
Use clean water and clean
container (not a dirty drum
or wheelbarrow).
Add Rhinolite to water.
Mix-aerate.
N.B. Do not add anything more
to this batch.
ISSUE DATE: DECEMBER 2005
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How to use RhinoLite
Do not mix more plaster than
you can use in 60 minutes.
(Not more than 2 bags
per mixing container).
Do not add
any foreign
matter to
Rhinolite.
Use it neat.
Use clean tools
for each batch.
SURFACES
Can be applied to brick as a
single application basecoat.
Can be applied
75 mm thick.
ISSUE DATE: DECEMBER 2005
Can be applied to ceilings 3-6 mm
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How to use RhinoLite
APPLICATIONS
Let sand cement surface dry.
Clean surface. Kill suction if
necessary by sprinkling water
onto the
surface.
Apply Rhinolite onto surface. Level it
out with a Darby or feathered edge
straight edge. Leave until partially set.
(Test with back of hand - Rhinolite must
stick to wall, not to your hand.
Use rubber
faced float
Only use enough water to
lubricate the float.
ISSUE DATE: DECEMBER 2005
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How to use RhinoLite
The magic float will
bring "fat" to the
surface - fast - and will
help smooth
the plaster.
Using a steel trowel
scrape the "fat" off
the wall.
Throw this "fat"
away. It is dead
plaster. Leave for
about 10 minutes.
Polish with a
steel trowel.
Clean all the tools and use fresh,
clean water
for the next
batch.
ISSUE DATE: DECEMBER 2005
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Paint Specifications for RhinoLite
In order to understand more fully the paint
specification as indicated on the RHINOLITE data
sheet and in more detail the manufacturer’s recommended specification, one must look at a few of the
background facts.
1. Bonding liquid. Solvent (often turpentine), transports resin into RhinoLite plaster.
evaporates,
resin
becomes
When solvent
hard
stabilising
porous/powdery surface. Therefore bonding liquid is
preferable for porous/powdery surfaces.
2. Plaster primer. Operates as above but pigmentation holds back some solvent and resin so less penetration is achieved. Plaster Primer copes with small
amounts of powder on well-plastered walls and can
be regarded as a ‘cover coat’ because of colour.
3. Cover coats. Industry norm is that a raw wall
requires 3 cover coats for a fully decorated monolithic surface. For RhinoLite use plaster primer plus two
coats of general paint. However, if bonding liquid is
used, 3 additional cover coats are still required as
bonding liquid is clear and not a cover coat.
NB Epoxy paints should not be applied to RhinoLite.
Note RhinoLite should be stacked level, in a dry place,
preferably in a building protected from damp and
weather. Stack on a pallet or lay down a damp proof
membrane when stacked on a concrete floor.
ISSUE DATE: DECEMBER 2005
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CreteStone
Basecoat plaster for application to concrete or plasterboard
CreteStone is a vermiculited, retarded hemihydrate Gypsum plaster
and a finishing plaster for application to concrete soffits, concrete
blocks and Rhinoboard. For internal use only.
APPLICATION
1. CreteStone to concrete surfaces
No hacking or slushing required on rough concrete surfaces. When
steel shuttering or grease has been used, or proprietary compounds
have been mixed with concrete, surface should be cleaned thoroughly. Use a wire brush to remove loose particles. Grease or oil is
always detrimental to the bond of plastering material. Therefore,
scrub concrete surfaces with cleansing agent to remove grease or
oil. Rinse with copious amounts of water till entirely clean. Apply
Grippon plaster bonding liquid using a brush or roller. While still
wet and tacky, follow with thin, tight application of CreteStone.
Using steel trowel, follow with filler coat to maximum 6mm thickness, press CreteStone into concrete surface. Pressure is essential to
remove air that could compromise the bond. Rule off and straighten plaster with feathered or straight edge. Apply additional
CreteStone to hollows between feathered edge and surface and rule
off again. As CreteStone stiffens, temper surface with water on
brush. Trowel to a smooth finish.
2. Application to Rhinoboard
Apply CreteStone neatly to not more than 6mm as follows:
Apply thin, tight coat well onto Rhinoboard, into wire scrim or
RhinoTape at joints. Follow with filler coat to maximum 6mm using
steel trowel. Pressure is essential to remove air that could compromise the bond. Rule off and straighten plaster with feathered or
straight edge. Apply additional CreteStone to hollows between
feathered edge and surface and rule off again. As CreteStone stiffens, temper surface with water on brush. Trowel to a smooth finish.
3. Covering Capacity
Applied 6mm thick the coverage will be approximately
11,5m2/40kg.
4 Decoration
Check surface is set hard, dry and dust-free before decorating. Do
not sandpaper CreteStone. Seal surfaces with oil or solvent based
sealer. Allow 24 hours to dry. Apply 2 coats paint as required.
NB Expoxy paints not to be applied onto CreteStone.
Note: CreteStone should be stacked level, in a dry place, preferably
in a building protected from damp and weather. Stack on a pallet
or lay down a damp proof membrane when stacked on a concrete
floor.
ISSUE DATE: DECEMBER 2005
ISSUE DATE: DECEMBER 2005
●
Marble Finish
●
●
Drylining
●
RhinoBed
●
●
●
●
●
●
RhinoGlide
Adhesives
Texturing
OTHER
Plastered
●
●
Finishing Coat
CEILINGS
●
Finishing Rhinoboard
Jointing Rhinoboard
●
Sand/Cement
●
CreteStone
●
●
Artex
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Block
Basecoat: Brick
RhinoLite
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WALLS
Plaster Finishing Systems
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System Selection Chart
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Product Guide Industrial Products
GYPSUM PRODUCTS
USE
PACKAGE
AGRIGYP
Soil conditioner. Water clarification. Deodoriser.
Bulk. Usually
ton loads.
GYPFIL
Component in glass manufacture.
40kg bags.
Filler in adhesives.
SUPERGYP
Filler in paints. Filler in adhesives.
25kg bags.
Setting additive in crack filler.
Cementitious component in fire prevention
sprays in mines, acoustics sprays in buildings.
Carving moulding and artwork.
Bonding of granite blocks for cutting.
40kg.
RHINOMOULD R
As for Rhinomould but setting is adjusted longer.
40 kg.
RHINOSET
Casting and moulding plaster used with fibre
reinforcing for architectural mouldings.
40kg.
Slip casting industry, ceramics, sanitaryware
working moulds.
25kg.
CRYSTACAL BASE
A hard dense plaster for use in giftware
25kg.
ESCAYOLA E35
Crackfiller manufacture. General purpose plaster.
25kg.
HYDROSTONE T B
Hardest of all plasters. Used in high
quality giftware, figurines, chess sets, etc.
45kg.
DENTAL PLASTER
White Dental models. Quicksetting.
25kg.
DENTSTONE KD
Yellow dental for hard dental models;
quick setting.
25kg.
GYPSUM PLASTERS
RHINOMOULD
ALFAMOLDE
Note: Industrial plasters should be stacked on a level surface in a dry place, preferably inside a building and
properly protected from damp and inclement weather. If industrial plasters is to be stacked on a concrete
floor inside a building, a damp proof membrane should first be laid down, or off the floor using a timber
pallet.
ISSUE DATE: DECEMBER 2005
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RhinoGlide
A SMOOTH SETTING PLASTER
DESCRIPTION:
RHINOGLIDE is a quick setting drywall joint filler
for patching, bedding and finishing.
This product has been developed specifically to assist
the drywall contractor to complete the jointing on
Drywall jobs within one day. Packed in 10 kg and
20 kg bags.
It is designed as a filler for plasterboard systems but
can also be used as an interior crack filler and for filling rough plaster surfaces prior to painting.
COVERAGE:
A 20 kg bag should be sufficient to finish completely
approximately 35 - 40 m of joint.
A 10 kg bag should be sufficient to finish completely
approx. 17,5 - 20 m of joint.
APPLICATION:
RHINOGLIDE is applied using the same tools and
procedure as described in the Rhino Drywall Hand
Jointing Application data sheet.
Note: Using RHINOGLIDE care should be taken whilst
jointing to clean off excess plaster and feather the
edges of the joint. This will reduce sanding and
disguise the joint better.
ISSUE DATE: DECEMBER 2005
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Grippon Plaster Bonding Agent
AVAILABLE IN:
20l, 5l, & 500 ml.
COVERAGE:
9 m2 per litre per coat (plastering).
35 linear metres per 500 ml (cornice).
USAGE:
Used as an adhesive to bond Gypsum Plasters to:
Painted Surfaces
Concrete surfaces
ISSUE DATE: DECEMBER 2005
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Gypseal
Package:
As a liquid in either 5l or 20l containers
ready to use.
2
Coverage: 7m per 1l / per coat.
DIRECTIONS
• Surfaces to receive GYPSEAL to be thoroughly clean,
dust free and dry.
• Remove any grease or oil with grade A thinners.
• Apply the GYPSEAL direct from the can with a
brush or roller in the normal way.
• For ease of application onto porous surfaces thin
the GYPSEAL with grade A thinners.
• For spray gun application mix 1:9 part thinners to
GYPSEAL.
• Use a rough-spray nozzle maintaining a pressure
2
of 4,2 kg/cm .
• Do not apply thinners during the application
process or irregularities in finish will result.
• To paint over GYPSEAL use a universal undercoat or
enamel paint.
• Clean all brushes, rollers, spray-guns etc. with
thinners immediately after use.
TO SEAL A RHINOBOARD SURFACE
BEHIND WALL TILES
• Apply two liberal coats of GYPSEAL.
• Take care to cover edges of cutouts for pipes etc.
• Allow each coat to dry completely before applying
another coat or before continuing tiling operation.
• For tile fixing use a good quality non-cement
based ready mixed flexible waterproof tile
adhesive.
HEALTH AND SAFETY WARNING
• Do not bring GYPSEAL into contact with a naked
flame.
• In areas of restricted ventilation, masks should be
worn or forced ventilation induced.
• Clean all brushes, rollers, spray-guns etc. with
thinners immediately after use.
ISSUE DATE: DECEMBER 2005
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Building Plaster Products and Accessories
PRODUCT
NAME
DESCRIPTION AND USE
PACKAGE AND SIZES
RHINOLITE
Lightweight basecoat and finishing Plaster
for brickwork, concrete blocks, concrete
and Rhinoboard and a finishing plaster on
to sand cement basecoats.
Coverage:
The approximate coverage
of a 40 kg bag of RhinoLite is:
2
2 - 3 mm
= 25 m
2
5 - 6 mm
= 11,5 m
2
12 - 15 mm
= 4,5 m
2
15 - 20 mm
=3m
Water Demand = 40 kg plaster / 22 litres water
The approximate coverage of a
10 kg bag of RhinoLite is:
2
2 - 3 mm
=6m
2
5 - 6 mm
= 2,88 m
2
12 - 15 mm
= 1,12 m
2
15 - 20 mm
= 0,75 m
Water Demand = 10 kg plaster / 5,5 litres water
CRETESTONE
A finishing plaster for application to Rhinoboard
or sand cement basecoats plaster.
Coverage: The approximate
coverage of a 40kg bag is:
2
6 mm
= 11.5m
Water Demand = 40kg plaster / 22 litres water
RHINOGLIDE
A smooth setting, sandable compound used as:
20kg bags and 10kg bags
Water Demand = 20 kg plaster / 9,2 litres water
Setting Time: 70-90 mins
Coverage: 35 - 40 m of Drywall
Joint per 20 kg bag.
Coverage: 17,5 - 20 m of Drywall joint
per 10 kg bag.
Water Demand =10kg plaster / 4,6 litres water
1. A quick setting Drywall jointing plaster
for both bedding and finishing.
2. An interior patching plaster to fill holes.
3. Used for sparkling plaster walls before
painting.
RHINOBED
An adhesive used for fixing decorative
mouldings and Rhino Cove.
20kg bags
Setting Time: 65 mins
Coverage: 40 lm per 20 kg bag.
Water Demand = 20 kg plaster / 10 litres water
COVEBOND
An adhesive for the fixing of decorative
mouldings and all cove cornices.
10kg
Coverage: 24 lm per 10 kg bag.
Water Demand = 10 kg plaster / 5 litres water
GRIPPON
A plaster bonding liquid for use on most
surfaces and specifically for:
1. RhinoLite/Rhinocrete to concrete surfaces.
2. RhinoLite/Rhinocrete to painted surfaces.
3. RhinoArt adhesive and Rhinobed Covebond
to painted surfaces.
500ml, 5l Tin & 20l Drum
RUBBER FLOAT
A float consisting of a dense sponge rubber
on a plastic base. Used in the finishing of
RhinoLite plaster.
Sold per unit.
DARBIES
An aluminium straight edge fitted with two
handles. Level RhinoLite Plaster when used as
a base coat on Rhinoboard, brickwork or
concrete. Used to move plaster from the
“high” spots to the “low” spots.
Length: 1 200
RHINOART
ADHESIVE
An adhesive for the fixing of
Rhino Art classic mouldings.
ISSUE DATE: DECEMBER 2005
2
Coverage: Average 9m /L/coat
Sold per unit.
10kg
Coverage: 20 lm per 10 kg bag.
Water Demand = 10 kg plaster / 5 litres water
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Guide to the use of Industrial Plasters
ORNAMENTAL AND GIFTWARE
Gypsum plasters are finding increased uses in the
manufacture of ornaments, statues and giftware.
Modern plasters are versatile and offer advantages
over the more conventional mediums such as clay
by reducing the time from manufacture to
completion.
Plasters do not need to be fired at high temperature, but merely dried at low temperature and they
are easily decorated with modern acrylic paints and
lacquers.
There are four basic requirements for producing
good plaster casts, they are:
- Good design
- Good plaster
- Good mould design
- Good finish
- an aesthetically
pleasing yet practical
design
* avoid sharp edges
and corners
* adequate uniform
thickness
* the shape must lend
itself to moulding
- the proper plaster
must be used, they
must be strong with
low water demands.
- the cast product will
only be as good as
the mould.
- split moulds should
be split along natural
planes.
- art work must be
good to make the
finished article
attractive.
Selecting the right plaster
The range of plasters available varies considerably
and each type has it’s own characteristic and use.
A high water demand will result in a soft plaster
suitable for carving or hand shaping. A low water
demand will result in a hard strong plaster that cannot be carved, this type is suitable for casting.
Slip casting plasters are designed for the ceramic
industry and their main characteristics is absorption
with medium hardness.
ISSUE DATE: DECEMBER 2005
Application
Characteristic
Carving
Slip Casting
Casts
Soft
Medium
Hard
Water Demand
ml/100g
80-90
60-70
20-40
Water Demand
This term refers to the amount of water required to
produce a pourable consistency.
it may be expressed as:
- Plaster / water ratio
- consistency
100/60
60
or as is common in the ceramic industry the inverse
of the above
i.e.
- water/plaster ratio
- consistency
60/100
60%
This booklet uses the standard of ml water per 100g
plaster (by mass).
For optimum strength always weigh out the quantities of water and plaster.
Batching
Fill the mould with water to determine the volume
of slurry required. Use the mix volume data on each
product data sheet to work out the batch size
requirements, e.g. mix only one batch at a time.
Example: Slip casting mould to be used with
Alfamolde 7PL
-
Measured volume of mould is 1200 ml
Mix volume : 90ml (at 67ml/100g plaster)
Water demand 67ml/100g plaster
Data available from Product Data sheets
Mix required
Water 1200 x 67 = 893ml
90
1
Plaster 1200 x 100 = 1333g
90
1
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Guide to the use of Industrial Plasters
Use these portions for your mix and if necessary
make multiples of this batch for casting more than
one similar mould.
Mixing Procedure
Successful mixing of gypsum plasters requires strict
adherence to specific standards and procedures.
The improvements in plaster formulations made in
recent years have resulted in more uniform
products, but to obtain the full benefit of these
improved products, procedures must be standardised.
An ideal plaster mix is one in which the plaster particles are completely dispersed in the water to produce a uniform, homogeneous smooth lump free
slurry. Extreme care must be taken to control such
variables as batch size, mixer design, water purity,
temperature and additives. The following information covers many of the factors that determine production of an ideal plaster mix.
Water purity
Water used in mixing plaster should be as pure as
possible. If water is drinkable, it is probably
suitable for mixing plaster. In some cases, water for
industrial use is taken from contaminated sources
and may be high in organic impurities that will
lengthen the setting time of the plaster.
Large amounts of soluble salts such as sodium chloride, sodium sulphate and magnesium sulphate in
the water can migrate to the surface of the cast
while drying.
The resulting efflorescence forms hard sports on
cast surfaces can result in variable absorption properties in finishing casts. Other chemicals in the
water may react with the gypsum to produce these
soluble salts. In general, any compound which has a
greater solubility than gypsum can produce efflorescence.
Water Temperature
Since gypsum has maximum solubility between 25
and 40ºC, variations in water temperature affect
setting time and can cause difficulty in control of
mixing time. Graph shows how the use of water at
various temperatures affects setting time.
ISSUE DATE: DECEMBER 2005
Plaster temperature
maintained at 21o c
20
Setting time - min
C Plast
18
16
0
40
80
Water temperature - o
Effect of water on setting time.
Water-to-plaster ratio
The water-to-plaster ratio (consistency) is the
amount of water used with a definite amount of
plaster. For example, a 70 consistecy mix would
mean 70 parts of water per 100 parts of plaster.
Consistency is always specified by weight.
When less water is used in the mix the setting time
may be faster, and the plaster will not be as fluid,
which may cause air bubbles in the cast pieces.
The density, hardness, strength and durability of
plaster casts are intimately related to the quantity
of water used in the mix. Therefore, it is extremely
important that the recommended water-toplaster ratio be followed for best results.
Soaking
Each plaster particle is surrounded by air, part of
this air is removed during shipping and handling
and part during soaking. Soaking allows each plaster particle to be saturated with water, making it
easier to disperse during mixing. Always add the
plaster to the water to avoid air entrapment.
Sprinkle the plaster into the water.
Plaster with good soaking properties will sink slowly into the water and become almost completely
wetted after 3 to 4 minutes. Shortcuts in soaking
adversely influence effectiveness of the mixing period and subsequently affect the quality of the plaster cast.
Mixing
Mixing the plaster slurry is a most important step in
producing plaster casts with maximum strength,
hardness and other important properties. Any
changes in mixing procedures will greatly affect
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Guide to the use of Industrial Plasters
Dry compressive strength - MPa
the finished product. Proper mixing disperses plaster particles in the water. The strength of the plaster cast is directly related to mixing since there is a
direct relationship between energy input during
mixing and the strength developed in the cast. The
graph below shows the effect of mixing time on
strength development.
Mixing Instructions
Sift or sprinkle plaster into water slowly and evenly.
Do not drop handfuls of plaster directly into the
water. Allow plaster to soak for 2 to 4 minutes,
then mix as required - generally 2 to 5 minutes - to
obtain a creamy slurry. Always add plaster to water,
never the reverse.
Hand mix - Generally acceptable for small batches
up to 5kg. However, since optimum physical
properties are in direct relation to energy input in
mixing, hand mixing will not result in a plaster cast
with the best properties.
14
12.5
11
9.5
8
1
2
3
4
5 6 7 8 9
Mixing time - min
10 11
Longer mixing means greater strength.
Where high strength is the primary requirement,
longer mixing times are desirable. Care must be
taken. However, not to mix into the setting stage
of the plaster since this decreases strength.
The graph below shows the effect of mixing time
on the setting of the plaster slurry. Varying mixing
times to control setting is acceptable to a limited
degree. Often large batches of plaster are undermixed to lengthen setting times stated so that the
caster can pour many casts from a batch. This practice jeopardizes strength, as discussed previously.
Generally, the batch size should permit pouring to
be completed within 5 minutes after slurry has
been mixed.
Vicat set time - min
C Plast
36
32
28
24
20
16
12
8
4
0
Mechanical mixing - For the best results, use a
high-speed, direct-drive propeller mixer with
mixing shaft set at an angle of 15º from vertical.
The propeller should clear bottom of container by
25mm to 50mm and the shaft should be about
halfway between center and side of the container.
Propeller rotation should force mix downward.
Keep all equipment clean to avoid accelerated set
of plaster.
Motors and mixing blades
(up to 25kg slurry)
For small batches
0,2 kW: 75mm, 3-blade,
25º - pitch propeller.
(25 –50kg slurry) 0,4 kW:
For medium batches
100mm or 125mm,
3-blade, 35º - pitch
propeller.
(50 – 100kg) 0,5 kW:
For large batches
100mm or 125mm,
3-blabe, 25º - pitch
propeller.
Propeller speed should not exceed 500 rpm.
Generally only one propeller is necessary, but if it
does not provide enough turbulence, two may be
used.
2
3
4
5
6 7
8 9 10 11 12 13
Mixing time - min
Effect of mixing time on setting time
To mix plaster properly for uniform casts, follow
steps:
1. Weigh plaster and water accurately for
each mix.
2. Follow timed soaking and mixing cycles.
Use an interval timer.
3. Use a mechanical mixer and a mixing
bucket of proper size and design.
ISSUE DATE: DECEMBER 2005
Cage-type or flat disc mixers ( rubber or metal) can
also be used for mixing industrial plasters and
gypsum cements. The flat-disc mixer introduces air
to foam the plaster slurry.
Continuous mixing
Several types of continuous mixers have been used
successfully for preparing large quantities of
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Guide to the use of Industrial Plasters
plaster. It is extremely important to maintain good
quality control practices, including consistency
checks, to assure uniformity of plaster slurry. Even
at the same water-to-plaster ratio, plaster casts
made with slurry prepared in continuous mixers do
not have the same properties as those made with
mechanical batch mixers.
in a specified time. Advantages of controlled drying
include:
Proper strength development
Uniform absorption
Increased production
Mildew prevention
Better paintability
Additives
Accelerators, retarders, aggregates, plasticisers, pigments and fibre reinforcements can be added at
the mixing stage.
Setting Time
Setting time is the period elapsing from the point
when the plaster is added to the water until the
mix becomes hard enough to support a Vicat
needle, used by all manufacturers in testing. The
time at which the plaster is used should be selected
to suit the manner by which the final form is
obtained. During the first portion of setting time,
the plaster mix is fluid and readily poured. Later in
the process, the material stiffens, it can still be
shaped or formed but will not pour. Once the
material has set, its form cannot be changed except
by carving or by adding fresh plaster mixes to it.
EFFECT OF DRYNESS ON COMPRESSIVE
STRENGTH
Compressive strength - MPa
C Plast
2500
2400
2300
2200
2100
2000
1900
1800
0
25
50
75
Percent excess water evaporated
100
Effect of dryness on compressive strength.
Gypsum strength increases only slightly until
93% free moisture has been removed.
Gypsum strength increases only slightly until 93% of
free moisture has been removed.
Forced drying
Drying Plaster Casts
Atmospheric drying can successfully be used for
smaller jobs and or batches. Atmospheric drying is
better in dry, hotter climates than wet or cold
climates. Atmospheric drying can be speeded up by
force air circulation blowing over the casts.
For uniform results and optimum physical
properties, plaster casts must be properly dried,
done by transferring excess water in the cast to the
surrounding air. For complete hydration in the setting process, plasters require about 18,6 part water
per 100 part water. To obtain a mixable
slurry, larger amounts of water must be used in
mixing.
After the plaster has set, any water above 18,6
parts is considered excess or “Free” and must be
removed from the cast by drying. Drying
equipment can be designed to remove excess water
To evaporate “ free” water from casts requires an
energy source. For each kg of water evaporated,
slightly more than 1 Gj of energy is required.
The same drying action takes place whether the
plaster cast dries in a workroom, outdoors or in a
dryer. Use of a forced-hot-air dryer speeds and controls the drying procedure.
As the cast sets or hardens, a chemical reaction
causes the piece to heat slightly so that excess water
begins evaporating from the cast.
When a new, wet cast is placed in a forced-hot-air
dryer, rapid evaporation begins. Initial evaporation
keeps the cast cooler than air temperature in the
dryer. Water from the interior of the cast moves to
the surface to replace evaporating moisture. As
evaporation continues, sufficient water does not
move to the surface to keep it cool.
The surface temperature rises, although the centre
of the cast is still moist. As the amount of
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evapouration is reduced, the cast’s surface temperature approaches the air temperature in the dryer.
Once the surface of the cast is up to air temperature, the rest of the free water in the cast evaporates
slowly, coming to the surface where, as vapour, it is
swept away. As this occurs, the entire cast warms
to approximate ambient air temperature, further
and further towards its centre. When the centre of
the piece reaches the temperature of the surrounding air, the drying process is complete.
Best Dryer Temperatures
The main physical limitation in drying a plaster cast
is the maximum temperature at which the dryer
operates.
Recommended maximum temperature is 45ºC.
Air Circulatin In Dryer
Drying studies on various materials show that
increasing air speed over plaster casts reduces
drying time.
Air must flow around each cast. Casts that are
crowded together dry very slowly. They should be
placed on racks and separated by runners so that
water vapour is able to escape.
COLOUR PIGMENTS
Wet
Wet colour, or dispersions of colour in liquid, can
be used as easily as dry pigment and in some cases,
they may be even easier to use. Dispersed colours
can be added directly to the water for each mix of
plaster. A very small quantity of colour dispersion
produces a fairly deep colour intensity.
Regardless of the colour used, putting colour in
the plaster will not produce a uniform shade of
colour in the dried cast. As the excess water
migrates from the plaster cast, areas of light and
dark colour concentrations appear. Thus, the use of
colour in the plaster does not replace surface
decoration, such as paints and lacquers.
Finally, the colour used in the plaster mix should
be checked for its compatibility with the surface
decoration, that will be used on the plaster cast. If
ISSUE DATE: DECEMBER 2005
the colour in the cast “bleeds” through the surface
decoration, it creates problems. If so consult the
supplier.
Dry
The use of dry colour pigments to tint plaster casts
is also feasible. First, be sure that the colour pigment used will not adversely affect the plaster,
some colour pigments may contain ingredients
which accelerate or retard setting time of the plaster slurry or may cause excessive pin holing in cast
surfaces. Always test compatibility on a small mix
before mixing a large batch. Use only enough
colour to get the desired end results and no more.
Heavy additions of pigment impair the physical
properties of the plaster cast. For example, additions of 10% dry pigment may reduce dry compressive strength by up to 30% and dry impact
strength by up to 50%.
Dry colour are best handled by adding them to the
water to be used for mixing the plaster. The pigment is completely dispersed in the water. Any
desired quantity of water can be premixed with
colour pigment, then used as needed by each person in the cast shop. Since many dry colour pigments are not water soluble, stir the coloured
water blend before it is used for mixing plaster.
CASTING
Solid
These pieces are usually rather flat (wall plaques)
or small pieces with relatively thin sections of plaster. After proper weighing, soaking and mixing,
the plaster is poured slowly into the mould. Be
careful to avoid trapping air at the face of the
piece as they will have to be patched later. To
break up such air bubbles, slurry is poured into the
mould and poured out again into the mixing container. After a short time, the mould is again filled
with slurry. Vibrate the filled mould by pounding it
on the work table. This action causes air bubbles to
rise to the back of the cast. The plaster is then
screeded off the back of the casting to give a flat
and smooth back.
If the casting is a wall plaque hanger should be
inserted into the levelled piece before the plaster
sets hard.
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Guide to the use of Industrial Plasters
Hollow or Slush
This method is used for large pieces to reduce the
weight of the piece and to speed drying. When
making hollow casts, use more than one mould at a
time. This is an efficient procedure that gives the
plaster time to thicken before successive pours are
made.
First the mould is filled 1/3 to 1/2 full. Then the plaster is slushed by rolling and tilting the mould until
its entire surface is coated. Excess plaster is poured
back into the mixing container. The second mould is
prepared similarly and the process repeated.
When making the second pour, make sure the first
coat has thickened enough to stay in place when
slushing the mould wall. The process is repeated
three or four times, until proper wall thickness is
built up. Thickness varies from piece to piece
depending on size and shape of casting. Timing is
important. If too much time elapses between
coasts, delamination may occur, causing a weak
casting. Hollow casting is an art, it takes practice to
learn successful techniques and timing.
FIBRE TYPES
Glass Fibre
Fibre must be loose chopped strand or open woven
mat, if not saturation of the fibre with
slurry will be difficult and will encounter problems.
Saturation is best achieved if the mat or fibre is prewetted.
For best results always ensure complete saturation
of the mat’ by the slurry.
Sisal
Natural sisal fibre is an excellent reinforcement. It is
usually cut into 75 - 150mm lengths and then put
through a teasing machine.
Hessian
Hessian sheets are also suitable for large areas, it
can be cut to the shape of the mould. Pre-wetting is
essential for proper saturation with plaster.
Using fibre mats
It is also possible to use inserts that displace plaster
and reduce the mass of the finished cast. Inserts
should be tapered for easy removal and should be
removed before final set takes place.
Prepare mats by cutting to the shape of your
mould.
Splash
Place mould down on the table. Mix plaster to plasticity. Splash the plaster on or over the surface of
the mould until it is 8 to 12mm thick. Next, take
sisal or hemp and dip or soak it in the plaster. Press
this plaster-soaked sisal against the built-up plaster
coating, smoothing the surface with your hands.
This technique is used to increase strength and
reduce weight of large flat pieces.
Pour a thin layer of plaster slurry into the mould
and spread out evenly.
Soak the mat in water and squeeze out the excess.
Place the mat in the mould and daub or pat the
matting into the slurry. Make sure that entire
surface is saturated with plaster slurry before pouring more slurry. Repeat the process until the desired
thickness has been achieved.
Reinforcement
Softer plaster can be made more durable by the
addition of fibres, especially on large flat or curved
mouldings.
Using chopped Strand fibre
Stands maybe 3 to 20mm long and are usually
mixed in with the dry plaster powder. Longer
strands tend to get tangled in impellers of mechanical mixers.
Fibre addition is usually in excess of 5% by mass of
the plaster, the higher the fibre content the
stronger the final product.
Using Sisal Fibre
The teased sisal is shaped into the mould shape,
removed and laid alongside the mould.
Fibre can be in the form of mat, webbing, woven,
continuous or random configurations.
Slurry is poured into the mould and the fibre then
daubed into the slurry. Saturation is much easier
with this type of fibre and a good strong cast is
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Guide to the use of Industrial Plasters
obtained due to the random configuration of the
fibres.
TRIMMING AND PATCHING
After removing the casting from the mould, there
may be some fine, rough edges, small bubble or pin
holes that must be trimmed off and filled.
Trim and patch the cast when it is wet or as soon as
possible after it is removed from the mould. If the
casting has dried, the area to be patched should be
moistened with water.
Trim fins and
rough edges with
the edge of a
knife or an open
wood rasp. After
using the rasp on
wet plaster, clean
it with a wire
brush, before the
plaster in the
opening of the
rasp sets hard.
Knife
Enlarging holes before filling
Final finishing of edges can be done with sand
paper once the cast had dried. Not all hard plaster
casts can be sanded.
FINISHING PLASTER
There are many ways to finish plaster casts. Choose
the one that works and looks best for a particular
piece to be finished. Some ways to finish gypsum
are : painting, metallic leafing, rub-on waxing,
flocking, polyester or resin coating, plastic
spraying, electroplating and staining. Accessories
can also be added : wiggly eyes, eyelashes,
whiskers, felt, yarn, novelties, long pile fur, braid,
glitter and even feathers. When it comes to
selecting the finish, imagination is the only
limiting factor.
General Recommendations
First, make sure of a good casting. Fill the holes and
sand off seams. Make sure the piece is properly
dried. Always seal the dried plaster gypsum cast
with shellac, lacquer, or acrylic before finishing. This
helps obtain a uniform paint finish and improves
the surface for other type of finishes. Quick drying
lacquer, applied by brush or spray, is an excellent
sealer for gypsum.
ISSUE DATE: DECEMBER 2005
The correct procedure is to thin the sealer so that
the cast readily absorbs the first coat. Apply an
unthinned second coat after the first coat has
thoroughly dried.
Paint
There are many excellent paints for finishing
plaster casting. However, first and foremost, the
plaster cast must be dry. If not, paint will not stick,
or it will blister and peel off later. Base coats and
finishing paints can be lacquer, acrylic, latex or
enamel. Selection depends on personal choice and
availability of the desired paint. Contact a paint
manufacturer for their recommendations.
Metallic Leaf or Foiling
A process of covering the plaster cast with thin
metal foil. It is probably one of the oldest
methods for finishing plaster used by some
sixteenth and seventeenth century picture frames,
Metal leaf is available in silver, gold and some
burnished/variegated colours. Metallic leafing is a
slow process, but its effects can be obtain in no
other way. Basically the plaster cast, base coat or
undercoat is sealed with a colour similar to surface
foil.
Next, an adhesive is applied, the foil laid-up and
pressed into deep areas with a brush. Foil is added
until the entire surface is covered. Sometimes a
stain is added over the foil, then coats of clear
acrylic are sprayed to set the stain.
Rub-on Wax
These colours in paste wax form are used to
accentuate the piece. To use them, seal the casting
and base coat with paint, then rub on the wax to
accentuate metallic or pastel areas, or completely
flood a casting with wax.
MOULD MAKING
Models
The model should be checked for any flaws.
Patching or repairing should be done, first, with
clay or plaster. Whenever copies are made, some
details are lost; therefore make certain the model
has desired detail on the cast. When the model is
perfect, it can be fastened to any smooth flat
surface such as glass, hardboard or plywood.
If the model is a porous material such as wood,
plaster, concrete, ect., it should be sealed with
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thinned orange shellac and thoroughly dried. If the
model is made of non-porous materials such as
metal, glass or glazed ceramics, ect., a sealer coat
may not be needed.
Moulds
Moulds can be made of a variety of materials. All
moulds, however, are grouped into two general categories.
Rigid
Material may be wood, plastic, or glass fibre
moulds. Vacuum formed plastic moulds are used
extensively when a low-cost, two dimensional
mould is desired. Several thousand mould designs
are available, varying in size from a few inches to
two by four feet. If handled with care they
produce 25 to 100 plaster castings. Most moulds
require back-up support during casting. Support is
obtained by the use of a case mould cast from
plaster on the reverse side of the mould face.
Caution
Plaster expands when it sets. Rigid moulds such as
wooden moulds could resist this expansion and
cause severe bulking of the cast.
Flexible
Flexible mould may be made of gelatine, latex, cold
compounds, hot melt, polysulphide, urethane
elastomers or silicone materials having good
strength and elasticity. Flexible moulds are a
necessity for art work involving complicated
figurines. They are expensive and may require
several days to several weeks to complete. A backup shell is almost always necessary to support the
shape when pouring the plaster.
Flexible moulding materials fall into three major
groups : Each material is ideally suited for a
specific application and usage. Which to use is
determined by job requirements.
Latex rubber – These have a low raw material
cost, because less material is used than other flexible material. If properly cared for, latex moulds last
for years and hundreds of casts.
They require a back-up shell of plaster or glass fibre
to hold the mould shape while pouring. In some
cases, latex moulds take several weeks to make
because the time between coat applications is 10 to
12 hours. Multiple coats (25 to 50) may be needed
to get the desired thickness for a
ISSUE DATE: DECEMBER 2005
particular model. The most common way to apply
latex is by brush; however it may be sprayed or
dipped. Dipping reduces the time required to make
the moulds, but is limited to simple non-seam glove
moulds. Latex stretches but regains its original
shape. Latex moulds are used where high tolerance
and dimensional stability are not
important, such as in the hobby and craft industry.
Cold moulding compounds – silicones, polysulphides and urethanes are include in this category.
Each comes in different grades, strengths,
hardness, flexibility’s and colours. Some are more
dimensionally stable than others. Cold moulding
compounds offer better dimensional stability and
faster mould preparation than latex. Moulds can be
made in days instead of weeks. Cold moulding compounds, usually consist of 2 or 3 components. These
must be weighed carefully and mixed properly in
order to achieve good results. When selecting a cold
moulding compound to meet the needs of a project, discuss your job requirements with the manufacturer or distributor in your area. New materials
are being developed every year. Store moulds in a
cool, dark place and in immediate
contact with the model that has been sealed with
high quality orange shellac (not lacquer), a porous
model will cause mould shrinkage due to the migration of the plasticiser from mould to model. Moulds
not stored in contact with model may become distorted.
Hot Melts – Similar to cold moulding compounds in
the style of mould produced, hot melt moulding
material must be heated to a liquid before pouring
to make the mould. With recent improvements in
cold moulding compounds, hot melts are used in
only a very few operations. Exercise extreme caution when using hot melts.
TROUBLE SHOOTING TIPS
Problems occasionally result from improper practices
and application procedures. Cure or correction of
the undesirable effect is listed below the cause.
Quick Set of Plaster Slurry
Definition : Plaster sets before sufficiently soaked
and completely mixed.
Cause A
: Contaminated plaster.
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Cure A : Determine if plaster became
contaminated after removal from bag.
Do this by mixing plaster from the
storage bin in one mix , then under
identical conditions use plaster directly
from the bag for a second mix.
Any lumps of set-up plaster in bags or
bin should be removed. If both mixes
set too fast and do not appear
contaminated, any of the following
causes may be present.
Note: Paper bags are usually wrinkled where wet,
and lumps have a smooth side next to paper. Carrier
inspection should be initiated as the carrier is
responsible for this damage.
Cause B : Dirty mixing equipment.
Cure D
Cure B
Cause C : Plaster has become wet in storage.
Cure C
: Store plaster in warm, dry, ventilated
place, keep off damp floor.
Cause D : Packing lumps in bags of plaster.
: Clean mixing equipment to remove set
plaster or other contamination. Dirty
equipment shortens setting time.
: Do not store plaster in stacks higher
than ten bags. Always rotate stocks,
using older plaster first. Packing lumps
usually are the result of lengthy storage.
Never use lumpy plaster, it does not
make good casts.
Cause C : Impure mixing water.
Cure C
: If excessive alum, chloride or sulphate is
present in the water, plaster mix will set
too quickly. Check set by making a mix
with distilled water. Plaster should
always be mixed with water fit to drink.
Slow Set of Plaster
Definition : Plaster unusually slow in setting.
Cause
: Contamination.
Cure
: Confirm that plaster has not become
contaminated by sugar, glue or organic
acids. Then accelerate set by mixing
faster, mixing longer, using warmer
water or plaster to increase temperature
of slurry, or all of the foregoing in
combination.
Soft Casts
Definition : Soft casts after drying.
Cause A : Consistency is too high (mix is too thin).
Cure A
: For sufficiently hard casts, mix plaster at
recommended ratio.
Cause B : Casts have been “burnt” or calcined in a
dryer.
Cure B
: Regulate temperature of dryer at about
40 ºC and remove casts as soon as they
are dry. If exposed too long,
completely dry casts calcine and become
chalky on the surface at temperatures in
excess of 45ºC.
Lumpy Plaster
Pinholes in Casts
Definition : Moulds develop small holes in surfaces
after being used for only a short time.
Cause A : Plaster has absorbed moisture.
Cause
: Improper mixing and soaking of plaster.
Cure A
Cure
: Use a good plaster. Sift plaster into
water evenly. Do not allow large
quantities to fall into water at one time.
Let plaster soak completely so all
particles are wetted. Thoroughly
mix with a mechanical mixer with the
propeller adjusted so that air is not
whipped in. Air entrainment, a wide
spread defect, should be constantly
guarded against.
: Equip plaster bin with tight-fitting lid to
prevent absorption of moisture from the
air. Keep bin closed so water cannot
splash into bin.
Cause B : Plaster has become wet en route to your
plant.
Cure B
: Bags showing evidence of water should
be examined before carrier is relieved of
responsibility.
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Rough Surface on cast
Definition : Casts feels like sandpaper.
Trapped Air in Cast Surfaces
Definition : Voids in cast surfaces.
Cause
: Large particles in plaster slurry settle out
against face of case mould.
Cause
Cure
: Mix until plaster “cream”, slurry is then
sufficiently thick to prevent settling.
Cure
Cracked Casts
Definition : Large and/or hairline cracks in casts.
Cause A : Abusive handling.
Cure A
: Handle casts properly. Wet casts have
one-half their ultimate dry strength.
Cause B : Thermal shock.
Cure B
: Do not expose hot casts to cold air
drafts.
Cause C : Shrinkage cracks.
Cure C
: Dry at moderate temperature.
Calcination due drying at extreme
temperature causes shrinkage
and racking.
Mildew on Casting
Definition : Black, green or reddish-brown spots
of varying size.
Cause A : Cast not dried properly.
Cure A
: Remove spots by washing with water or
dilute solution of bleach or fungicide.
Oven dry casts thoroughly and, if
possible, reduce humidity of air in
contact with cast.
ISSUE DATE: DECEMBER 2005
: Trapped air in mould faces due to
improper pouring.
: Pour plaster while still fluid. Start
pouring plaster into the deepest portion
of the cast. Agitate cast so trapped air
rises and fluid plaster fills all cavities of
the cast mould.
Paint Peeling
Definition : Paint will not stick or it blister and/or
peels off.
Cause
: Plaster cast has not been properly dried.
Cure
: Dry cast thoroughly before painting.
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Health & Safety Data
1. COMPOSITION / INFORMATION ON INGREDIENTS
SKIN CONTACT
Composition is formulated from calcium sulphate dehydrate and other minor ingredients.
Health hazard
- May cause irritation to sensitive
skins.
The health and safety risks of the ingredients have been
identified by the various suppliers to BPB Gypsum, but
have all been accepted as intrinsically safe within the
confines of use.
Precautions
- To avoid prolonged or repeated wet
contact – wear impermeable gloves.
- To avoid body contact, wear
protective overalls and footwear.
The ingredients referred to are at concentrations less
than 1 % (m/m).
The gypsum used in BKF98 is a phosphogypsum with a
pH range from 3, 5 to 7.
Where mixed with water it may give off a slight acidic
odour.
- Apply a barrier cream to the hands
to reduce the affect of contact.
First Aid
- Wash the affected area thoroughly
with soap and water. If skin
irritation persists seek medical
advice.
DISPOSAL
INHALATION
The product should be disposed at a tip designed for
building products or an authorized landfill site. Spillages
can be collected by vacuum, brush, shovel or mechanical
loaders as appropriate. In dealing with dry spillages, care
should be taken not to raise excessive dust. It should
preferentially be kept out of reach of children.
Health hazard
- May cause irritation.
Precautions
- Ensure adequate ventilation when
working with BKF98 powder. If dust
levels cannot be controlled by
ventilation, suitable (recommended
class FF2) dust masks should be
worn.
First Aid
- If irritation occurs, move to fresh air.
Should any symptoms persist, obtain
medical assistance.
2. HAZARDS IDENTIFICATION
May irritate eyes or sensitive skin. Dust may irritate respiratory system.
May produce an acidic solution on contact with body
moisture.
INGESTION
3. HEALTH HAZARDS, PRECAUTIONS AND FIRST AID
Health hazard
- The swallowing of small amounts of
BKF98 powder is unlikely to cause
any significant reaction.
Precautions
- Avoid ingestion by taking normal
hygiene precautions.
First Aid
- Wash out mouth and give patient
plenty of water to drink. Do not
induce vomiting.
EYE CONTACT
Health hazard
Precautions
First Aid
- BKF98 powder or admixtures with
water can cause irritation.
- Ensure adequate ventilation when
working with BFK98 powder, Safety
goggles should be worn in situations
where powder or splashes are likely
or where there is a risk of powder or
BKF98 mixes entering the eyes.
- in the event of eye contact wash the
eye immediately with plenty of clean
water for 10 minutes. Seek medical
attention if required.
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Health & Safety Data cont.
4. FIRE AND EXPLOSION HAZARDS
9. ECOLOGICAL INFORMATION
None
Gypsum is slightly soluble in water and phosphogypsum
can form acidic solutions. Gypsum (including phosphogypsum) is an approved product for soil conditioning in
the agricultural trade when applied correctly. It is also
utilized for water clarification.
10. DISPOSAL CONSIDERATIONS
- Thermal Decomposition at > 1450ºC
will evolve toxic and irritant vapours
(Sulphur oxides).
Non-combustible and in inhibits
spread of flames. Extinguishing
media: As for surrounding Fire.
(Fighting Protective Clothing: A) self
containing breathing apparatus and
suitable protective clothing should
be worn.
5. ACCIDENTAL RELEASE MEASURES
• Control and suppress dust formation. Vacuum or
sweep up transfer to a suitable container.
• Prevent product contaminating drains as a powder or
a slurry due to possible blockages through settlement.
6. HANDLING AND STORAGE
• Minimize and control dust when opening bags,
mixing product or handling in bulk systems.
• Avoid prolonged or repeated contact with the eyes or
on the skin.
• Wear protective clothing when mixing powder
product or working with wet product.
• Supplied in 1t bags or in bulk tankers. Appropriate
standard techniques for handling and stacking of bulk
bags should be used.
Dispose at an authorized landfill site or tip for building
products in accordance with local and national controls.
11.
TRANSPORT INFORMATION
Not classified as hazardous for transport. Make sure the
product is properly contained.
12.
TOXICOLOGICAL INFORMATION
The main component of BKF98 is calcium sulphate dehydrate (gypsum). Gypsum has been used in a wide variety
of applications over a long period of time. In the dehydrate and hemihydrate form, it finds widespread use in
medicine as plaster of paris. There is no evidence of any
long term effects associated with the dehydrate. The
presence of sulphate at high concentrations is known to
have a laxative effect. These effects are temporary
13.
OTHER INFORMATION
Hygiene Advise
- Contaminated clothing should be
removed and washed before re-use.
7. EXPOSURE CONTROLS
Occupational exposure limits for gypsum as for
Occupational Health and Safety Act (Act 89, 1130).
Substance:
Total Inhalable:
Total Respirable:
Gypsum
10mg/m3 8 hr TWA OEL-RL
5mg/m3 8hr TWL OEL-RL
8. PHYSICAL AND CHEMICAL PROPERTIES
Form
Specific gravity
Odour
Solubility in water
PH
:
:
:
:
:
ISSUE DATE: DECEMBER 2005
- After use, the skin should be washed
thoroughly with soap and water.
Grey to white powder
0, 8 to 1,2g/cm3
None to slightly acidic
Slightly soluble: ± 2,4g / 1
4 to 8
Notice to User:
- This Safety Data Sheet should not
constitute the users’ own workplace
risk assessment.