GB18588-2001
Limit of ammonia emitted from the concrete admixtures
混凝土外加剂中释放氨的限量
GB 18588-2001 is a current mandatory Chinese national standard for Limit of ammonia emitted from the concrete admixtures. It appears in the Electronics compliance cluster with a testing methods focus and has an implementation date of Jan 1, 2002.
Applicability depends on product scope, certification route, competent authority notices and transition rules. Requst for the translation or verify source before using this record in a compliance decision.
Compliance overview
Scope and applicability
GB 18588-2001 applies to various types of concrete admixtures used in buildings that possess indoor usage functions and are capable of releasing ammonia. This standard is strictly limited to indoor construction applications and explicitly excludes concrete admixtures used in bridges, highways, and other outdoor engineering projects. It serves as a crucial environmental and safety protocol for indoor building materials.
Technical requirements
The core of this standard is defined in Chapter 4, which is established as a mandatory technical clause. It strictly stipulates the maximum allowable emission threshold for ammonia released from the admixtures, calculated as a mass fraction. Compliance with this specific emission limit is legally required for all relevant manufacturers to ensure indoor air quality safety. The standard dictates that any product exceeding this specified regulatory threshold is deemed non-compliant and is prohibited from being sold in the Chinese market.
Testing methods
The evaluation of ammonia release is conducted via a distillation-titration method detailed in the normative appendix. The procedure involves distilling ammonia from an alkaline solution, absorbing it using an excess of a standard sulfuric acid solution, and subsequently back-titrating the unreacted acid with a standard sodium hydroxide solution. Methyl red-methylene blue mixed indicator is utilized to determine the titration endpoint. The standard also outlines specific sampling rules, requiring random 1kg samples to be divided for testing and sealed retention for three months.
FAQs
What products are regulated under GB 18588-2001?
It applies to concrete admixtures used in buildings with indoor usage functions. It does not apply to concrete admixtures used in outdoor engineering projects such as bridges, highways, and other exterior constructions.
What is the maximum allowable limit for ammonia emission under this GB standard?
The standard sets a strict mandatory limit, specifying that the mass fraction of ammonia emitted from the concrete admixtures must be less than or equal to 0.10%.
What testing method is specified to measure ammonia release?
The standard utilizes a post-distillation titration method. The ammonia is distilled from an alkaline solution, absorbed by an excess of standard sulfuric acid solution, and the remaining acid is back-titrated using a standard sodium hydroxide solution.
The summary above provides a high-level overview of GB 18588-2001. To ensure complete compliance for your construction materials entering the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 18588-2001 today to access all detailed parameters, distillation procedures, and calculation formulas.
Applicability hints
- Type
- Method
- CCS
- Q12
- ICS
- 91.100.30
- Competent department
- Ministry of Industry and Information Technology
- Technical committee
- Ministry of Industry and Information Technology