CLEANING OF SURFACES ABOUT TO BE COATED. No coating slin11 be applied to a prepared steelwork surface tlint
is contaminated w i L h o i l , grease, perspiration, rusL ur cliririlcai d e p o s i t s u i i t i l such siirfare Iias been ndequately
cleaned. Uncoated steel s h a l l not be touched w i t h bare hands. Where contaminntion lias occurred, i t
s h a l l be removed with the use of s u i t a b l e e m u l s i f i a b l e d e t e r g e n t , aqueous detergenl or a l k a l i n e cleaning
s o l u t i o n s . I n e x r e p t i o n a l circumstances, f o r limited areas and to avoid spreading of t h e contaminants,
contamination IMY be removed by repeated wiping of the area w i t h clean rags soaked with fast-evaporating
c l e a n i n g s o l v e n t s .
Degreasing of steelwork s h a l l be followed by r i n s i n g w i l l 1 wilter to remove resitlues (excrpt wlitxrt. a limited
area has been solvent wiped).
Where any c o a t has oxidized o r become excessively hard, i t s h a l l be abraded to a matt f i n i s h and cleaned
p r i o r to the a p p l i c a t i o n of f u r t h e r c o a t s . Solvent wiping IMY be required where c a l l e d f o r by the nunufart
u r e r , i n which c a s e o n l y t h e manufacturer's approved solvent s h a l l be used.
Prior to the a p p l i c a t i o n of any c o a t , the quantily of dust and debris present on tlie s u b s t r a t e , when
determined i n accordance with SABS Method 769, s h a l l not exceed 0,3 X . However, because of the d i f f i c u l t y
in making comparisons w i t h the r e f e r e n c e s t a n d a r d s given i n the method, on-the-job t - . e s t s , i f deemed
necessary, s h a l l be c a r r i e d out aL the commencement of the c o n t r a c t , and reference t a p e s produced and
agreed upon as reference standards. These tapes s h a l l then serve as the agreed standard to be achieved
the c o n t r a c t .
Unless otherwise approved, coats s h a l l only be applied to moisture-free s u r f a c e s .
5.7 COATING SYSTEM. The coating system s h a l l be a s s p e c i f i e d i n the project s p e c i f i c a t i o n and s h a l l be app
a t the l o c a t i o n s p e c i f i e d .
5.8 APPLICATION OF PAINT COATINGS. No coating s h a l l be applied i f Llie temperature of the steelwork is less
than 3 "C above dew point o r outside the range 5-35 'C, unless otherwise s p e c i f i e d i n the project spec
for
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a t i o n or agreed to by Lhe paint manufacturer.
The method of coating a p p l i c a t i o n s h a l l comply w i t h the manufacturer's recommendations and data s h e e t s .
Multicomponent m a t e r i a l s s h a l l be appljed with due c a r e , the s p e c i f i e d a p p l i c a t i o n techniques being used.
A l l coatings s h a l l be s u b s t a n t i a l l y f r e e from t e a r s , r u n s , c u r t a i n i n g , foreign inclusions and nwterial s u r -
face d e f e c t s and shall, i n a d d i t i o n , be free from misses. When tested i n accordanre w i t h 7 . 3 . 9 , coatings
t h a t are to be submerged fihall be free from elecLrica1 i n s u l a t i o n d e f e c t s , inrluding pinholes and inclusions.
Maximum and minimum i n t e r c o a t i n t e r v a l s s h a l l comply with Lhe paint manufacturer's recommendations, taking
cognizance of ambient conditions.
A l l metal edges, upstands, welds, b o l t s and nuts s h a l l be adequately c o a t e d . If s p e c i f i e d i n the project
s p e c i f i c a t i o n , s t r i p e coating w i t h an a d d i t i o n a l coat of paint s h a l l be applied a � t e r the i n i t i a l priming.
The colour of each coat s l i a l l be d i f f e r e n t from t h a t of the previous c o a t , except i f two f i n i s h i n g coats
of the same colour are necessary to achieve colour uniformity. Unless the primer is of a weldable type,
steel edges t h a t a r e t o be welded a f t e r priming s h a l l be left 'uncoated f o r a distance of 50 mm from the
welding edge.
S t e e l t h a t is Lo be embedded i n concrete s h a l l be coated over unless otherwise s p e c i f i e d i n the p r o j e c t s p e c i f i c a t i o n . Fasteners t h a t are to be embedded i n concrete
s h a l l be protected as s p e c i f i e d i n the project s p e c i f i c a t i o n .
Unless otherwise s p e c i f i e d , nlating steel surfaces s h a l l each receive one coat of primer.
F r i c t i o n - g r i p areas s h a l l be t r e a t e d a s s p e c i f i e d i n the project s p e c i f i c a t i o n .
Surfaces t h a t w i l l be i n a c c e s s i b l e for coating a f t e r f a b r i c a t i o n o r e r e c t i o n s h a l l receive the f u l l spec
i f i e d coating system p r i o r t o f i n a l f a b r i c a t i o n or e r e c t i o n .
A l l coating components, part i r u l a r l y two-component or multiromimnent m t e r i n l s , s h a l l be thoroughly mixed
u n t i l a homogeneous mixture is achieved. The mixture shall br rreqiiently a g i t a t e d during, a p p l i c a t i o n t o
keep the s o l i d s i n suspension. The preparation time and pot lice of t h e s e m a t e r i a l s s h a l l be closely adhered
t o .
Zinc-rich coatings s h a l l be conLinuously a g i t a t e d i n n s u i t a b l e pressure pot to ensure uniform dispersion
of the zinc p a r t i c l e s i n the l i q u i d component.
5.9 APPLICATION OF METAL COATINGS (AOT-DIP GALVANIZING, METAL SPKAYlNC). A l l HDG sha1L comply w i t h the
requirements of SABS 763 or SABS 934, as a p p r o p r i a t e , and slirill comply w i t h the provislon of SARS 0214.
A l l thermally sprayed metal coatings and Llie s e a l i n g Llwreof s h a l l comply wiLh the requirements of
SABS 1391 and s h a l l be applied i n accordance w i t h tlie information given i n Llie appropriate of the
appendices. I f a galvanized surface is to be coated to provide a duplex system of c o a t i n g , tlie galvanized
surface s h a l l f i r s t be cleaned and prepared a s recommended i r i SABS 064 o r i n accordanre w i t h the coating
manufac t u r e r ' s recommendat ions.
No d r i l l i n g , c u t t i n g , welding o r machining s h a l l be c a r r i e d ouL a f t e r metal coating. Unavoidable damage
s h a l l be repaired i n accordance with 5.10.
5.10 REPAIR OF DAMAGED COATINGS. Damaged a r e a s s h a l l be cleaned dowii to a clean metal condition or to an
undamaged coated s u r f a c e .
Spot r e p a i r s s h a l l r e - i n s t a t e each of the previous c o a t s , or s h a l l be made using an approved patching
m a t e r i a l . The patch s h a l l extend at l e a s t 25 mni over adjacent s u r l a c e s which s h a l l have been prepared by
f e a t h e r i n g with s u i t a b l e abrasive paper.
The r e p a i r of metal coatings s h a l l be t o a procedure approved by the Engineer. (Sre a l s o SABS 763.) Repair
procedures s h a l l include t h e a p p l i c a t i o n of appropriate metal sprays, s p e c i a l s o l d e r s or an approved zincr
i c h coating.
Excessive r e p a i r s may require t h a t s p e c i a l remedial procedures be agreed upon.
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