GB16993-2021
Safety regulations for avoid working under hazardous condition of oxygen deficiency in enclosed spaces aboard ships
防止船舶封闭处所缺氧危险作业安全规程
GB 16993-2021 is a current mandatory Chinese national standard for Safety regulations for avoid working under hazardous condition of oxygen deficiency in enclosed spaces aboard ships. It appears in the Chemicals compliance cluster with a product safety focus and has an implementation date of Nov 1, 2021.
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
This standard applies to operations involving personnel entering enclosed spaces aboard commercial ships during navigation, berthing, and operational processes. It covers various ship compartments including cargo holds, double bottoms, fuel tanks, ballast tanks, pump rooms, and boiler spaces. It is mandatory for all maritime operators and personnel involved in shipboard enclosed space entry within Chinese jurisdiction. The standard specifically addresses the prevention of oxygen deficiency and does not apply to routine open-deck activities.
Technical requirements
GB 16993-2021 establishes comprehensive safety procedures to mitigate the risks of oxygen deficiency and hazardous atmospheres in shipboard enclosed spaces. The core technical requirements mandate strict air quality parameters: oxygen concentration must be maintained between 19.5% and 23.5% by volume, toxic gases must comply with GBZ 2.1 occupational exposure limits, and combustible gas levels must not exceed 1% of the Lower Flammable Limit (LFL). Operations cannot commence until these atmospheric conditions are verified and maintained. The standard outlines rigorous preventive management protocols. Before entry, a formal risk assessment and safety briefing must be conducted. Personnel must obtain an approved entry permit prior to accessing any enclosed space. The standard also details specific requirements for safety protective equipment, including the mandatory provision of self-contained breathing apparatuses (SCBA), calibrated gas detectors, and full-body harnesses when fall hazards exist. For ongoing operations, the standard requires continuous ventilation and air monitoring. If operations are interrupted or ventilation ceases, the space must be re-evaluated and re-tested before re-entry. Untrained or unequipped personnel are strictly prohibited from attempting emergency rescues without appropriate self-contained breathing apparatus, as this standard explicitly forbids the use of filter-type respirators for rescue operations in oxygen-deficient environments.
Testing methods
The standard specifies two primary methods for air quality assessment: on-site detection using calibrated portable gas detectors, and laboratory testing conducted in accordance with GB/T 12301. Detection points must be strategically distributed based on the space's structure and cargo characteristics. Air testing must be performed after ventilation has been stopped and the environmental state has stabilized. Continuous monitoring is required during operations where atmospheric conditions may change, particularly during pipeline/valve work or when ambient temperatures rise.
FAQs
What types of ships and enclosed spaces are regulated under GB 16993-2021?
It applies to enclosed spaces aboard commercial ships operating in Chinese waters or under Chinese jurisdiction, including cargo holds, double bottoms, fuel tanks, ballast tanks, and pump rooms during navigation, berthing, or operational processes.
What are the main updates in GB 16993-2021 compared to the previous 1997 version?
The 2021 version significantly updates the 1997 standard by adding specific definitions for enclosed spaces, introducing mandatory risk assessments and entry permit systems, updating air quality limits, and adding comprehensive requirements for emergency rescue and drills.
How does GB 16993-2021 relate to international maritime standards?
The standard aligns its safety framework with international guidelines, notably referencing IMO Resolution A.1050(27) for entering enclosed spaces aboard ships, while enforcing strict Chinese national limits for air quality and occupational exposure.
The summary above provides a high-level overview of GB 16993-2021. To ensure complete compliance for your maritime operations and personnel safety in the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 16993-2021 today to access all detailed parameters, entry permit templates, and comprehensive safety procedures.
Applicability hints
- Type
- Safety
- CCS
- R09
- ICS
- 03.220.40
- Competent department
- Ministry of Transport
- Technical committee
- Ministry of Transport
Relationships
Replaces:GB 16993-1997