BS 3416:1988 download free.British Standard Specification for Bitumen-based coatings for cold application, suitablefor uáe in contact with potable water.
1 Scope
BS 3416 specifies performance and marking requirements for a range of bitumen•based solvent-borne coatings. It covers coatings for cold application by either brushing, spraying, rolling or dipping processes intended to give a coat for the corrosion protection and waterproofing of substrates including Iron and steel.
Two types, each with three classes, are included. All of these give films that are suitable for use on potable water tanks and cisterns as well as for general applications. The level of gloss of the finished film is not specified in BS 3416.
NOTE 1. These bitumen coatings are neither intended to withstand hot conditions, as on boilers, smoke stacks, etc., for which special coatings should be obtained, nor to resist contamination with mineral oils or paint solvents, all of which conditions will cause softening of the film.
NOTE 2. Guidance on the use of bitumen-based coatings is given in appendix A, BS 6493 and BS 6150.
NOTE 3. The titles of the publications referred to In this standard are listed on the inside back cover.
2 Definitions
For the purposes of BS 3416, the definitions given in BS 2015 apply together with the following.
2.1 bitumen. A viscous liquid, or a solid, consisting essentially of hydrocarbons and their derivatives, which is soluble in trichloroethylene and is substantially non-volatile and softens gradually when heated, It is black or brown In colour and possesses waterproofing and adhesive properties. It Is obtained by refinery processes from petroleum, and is also found as a natural deposit or as a component of naturally occurring asphalt In which it is associated with mineral matter.
NOTE. The international definition of bitumen relates its solubility to carbon disulphide but, in the United Kingdom, the safer materiel trichoroethyiene is used as the test solvent as examination has shown no significant difference.
2.2 bitumen-based coating. A liquid mixture of bitumen in a carrier (solvent or solvent mixture), usually paraffinic hydrocarbons, chlorinated hydrocarbons and aromatic hydrocarbons, with or without fillers, to give a consistency suitable for brushing, spraying, rolling or dipping in accordance with the recommendations of the manufacturer. The coating may exhibit thixotropy.
3 Classification
3.1 Bitumen-based coatings shall be classified into two types as follows.
(a) Type 1, without fillers.
(b) Type 2, with fillers.
3.2 Each type shall be further sub-classified as follows.
(a) Class A, using white spirit complying with BS 245 as the carrier.
(b) Class B, using either a solvent other than white spirit, or a solvent mixture with a flash point of or above 21 °C and below 32 °C as the carrier.
(c) Class C, using either a solvent other than white spirit, or a solvent mixture with a flash point of or above 32 °C as the carrier.
4 Sampling
Take and store In accordance with BS 3900: Part Al representative samples of not loss than 1000 mL of the coating either at the fillin9 stage or from one or more previously unopened containers. Condition the samples for at least 12 h at 23 ± 2 °C before carrying out any tests.
5 Flash point
When tested by the method described In B.1, coatings shall comply with the following.
(a) Coatings of classes A and C shall not flash at a temperature below 32 °C.
(b) Coatings of class B shall not flash at a temperature below 21 °C.
6 Drying and over-coating times
6.1 Surface dry time
When tested in accordance with the method given in B.21, films of coatings shall be surface dry:
(a) if type 1, in not more than 4 h; (b) if type 2, in not more than 8 h.
6.2 Over-coating time
When tested in accordance with B.2.2 the film shall show no cissing, crawling, sinking, lifting or wrinkling during application or after 24 h drying time.
7 Finish
When tested in accordance wIth 8.3, the film shall be smooth, opaque and free from sags or runs or other surface imperfections.
8 Protection against corrosion
8.1 Resistance to tap water immersion
8.1.1 When tested in accordance with B.4.1.1 the film
shall remain completely adherent to the substrate.
Any blistering shall not exceed the rating 2 (S3) of
BS 3900 : Part H2.
8.1.2 When tested in accordance with 8.4.1.2, the surface of exposed metal revealed shall show no signs of corrosion.
8.2 Resistance to artificial sea water immersion When tested In accordance with B.4.2 the film shall show no signs of breakdown. Any blistering shall not exceed rating 2 (S3) of BS 3900: Part H2:
9 Bend resistance
When tested in accordance with B.5, the film shall show no signs of cracking or of becoming detached from the substrate.
10 Effect on potable water
A coating of the product applied and left to dry In accordance with the manufacturer’s instructions shall comply with BS 6920: Part 1: 1988.
11 Shelf life
The product, If stored in unopened containers for 12 months at a temperature not exceeding 30 °C, shall meet the requirements of clauses 5 to 9. No separation shall take place which cannot be removed by stirring.
NOTE. In the case of thlxotroplc coatings, sufficient time, as advised by the manufacturer, should be allowed after any stirring to redevelop the thixotropy.
12 Marking
Each container of bitumen•based coating shall be clearly labelled with the following Information:
(a) the manufacturer’s identification;
(b) the number of BS 3416 and the
appropriate type and class of the product,
e.g. BS 3416:1988, type 1, class A;
(c) a statement that It Is suitable for use in contact with potable water;
(d) the nominal content by mass or volume;
(e) the batch number from which the container was filled;
(f) the month and year In which the batch was manufactured and a statement to the effect that the bitumen-based coating has a shelf life of 12 months when stored in unopened cntainers at a temperature not exceeding 30 °C;
(g) whether the coating Is suitable for brushing, spraying, rolling or dipping.