IS 3025:1993 is the Indian Standard (BIS) for use of water in concrete and masonry. IS 3025 is a comprehensive, multi-part standard detailing the physical and chemical testing methods for water and wastewater. In civil engineering, its various parts are primarily used to test the suitability of mixing and curing water for concrete, ensuring impurities like chlorides and sulphates do not exceed limits defined in IS 456.
Provides guidelines for the quality of water to be used in mixing and curing concrete and mortar.
Chemical limits (chloride, sulphate, pH, suspended/dissolved solids, organic matter) for water in concrete and mortar — read with IS 456 acceptance.
| Reference | Value | Clause |
|---|---|---|
| Code scope | Methods of sampling and test (physical & chemical) for water and waste water | Cl. 1 |
| pH range — concrete mixing water | 6.0 – 8.5 | via IS 456 Cl. 5.4 / IS 3025-11 |
| Max chloride — RCC mixing water | 500 mg/L (Cl⁻) | via IS 456 Cl. 5.4 / IS 3025-32 |
| Max chloride — PCC mixing water | 2000 mg/L | via IS 456 Cl. 5.4 |
| Max chloride — PSC mixing water | 500 mg/L (lower for PSC) | via IS 1343 / IS 456 |
| Max sulphate (as SO₃) — mixing water | 400 mg/L | via IS 456 Cl. 5.4 / IS 3025-24 |
| Max suspended solids — mixing water | 2000 mg/L | via IS 456 Cl. 5.4 / IS 3025-17 |
| Max organic matter (KMnO₄ value) | 200 mg/L | via IS 456 Cl. 5.4 |
| Max inorganic dissolved solids | 3000 mg/L | via IS 456 Cl. 5.4 |
| Initial setting time test — vs distilled water | Difference ≤ 30 min | via IS 456 Cl. 5.4 |
| Compressive strength of concrete — vs distilled-water mix | Not less than 90 % of control at 7/28 d | via IS 456 Cl. 5.4 |
| Total dissolved solids — typical test method | Gravimetric (180 °C drying) | Part 16 |
| Chloride determination — argentometric | Mohr / silver-nitrate titration | Part 32 |
| Sulphate determination — gravimetric/turbidimetric | BaCl₂ precipitation | Part 24 |
| pH determination — method | Electrometric (glass electrode) | Part 11 |
| Sample container — glass for organics | Borosilicate, dark for light-sensitive | Part 1 |
| Sample preservation — typical | 4 °C; ≤ 24 h holding (most parameters) | Part 1 |
| Sea water — restriction | Not permitted for RCC; PCC only with caution | via IS 456 Cl. 5.4.3 |
| Carbonate / bicarbonate (max as Na) | 1000 mg/L (mixing water) | via IS 456 Cl. 5.4 |