In high-risk environments such as petroleum, chemical, and pharmaceutical industries, the core prerequisite for selecting an explosion-proof air conditioner is "rating adaptation" — only by clarifying the explosion-proof rating standards can we ensure that the equipment accurately matches the explosion risk of the usage scenario. Combining international and domestic authoritative standards and industry practices, Winnex Air systematically breaks down the core dimensions of explosion-proof air conditioner rating classification to assist in safe selection.

I. Core Foundation: Composition and Meaning of Explosion-Proof Ratings

The explosion-proof rating is a core identifier for judging the scenario adaptability of equipment, prefixed with "Ex", followed by "explosion-proof type + environment category + temperature class", which intuitively reflects the equipment's safe adaptation capability:

Typical Rating Examples:

• Ex d IIB T4: Flameproof (d) design, suitable for factory Class II Group B (IIB) flammable gas environments, with maximum surface temperature meeting T4 group requirements (135~200℃). Commonly used in low-risk gas scenarios such as methane and propane (e.g., general chemical workshops);

• Ex d IIC T6: Flameproof (d) design, suitable for factory Class II Group C (IIC) flammable gas environments, with maximum surface temperature meeting T6 group requirements (85~150℃). Applicable to high-risk gas scenarios such as hydrogen and acetylene (e.g., fine chemical reaction areas).

II. Key Dimension 1: Explosion-Proof Type — The "Safety Protection Structure" of Equipment

Different explosion-proof types correspond to different risk prevention logics, among which flameproof type (d) is the mainstream choice for explosion-proof air conditioners:

Flameproof type (d): The equipment shell is made of high-strength materials (such as cast aluminum alloy), which can withstand the pressure generated by the explosion of the explosive mixture inside, while preventing flame or high-temperature gas from leaking out. This ensures that the external hazardous environment is not ignited, balancing safety and durability, and is suitable for most high-risk industrial scenarios.

III. Key Dimension 2: Explosion Hazard Area and Gas Category — The "Risk Level" of Scenarios

According to the type and concentration of explosive substances in the environment, explosion hazard areas and gas categories are divided into different levels, which determine the adaptation range of the equipment:

IV. Key Dimension 3: Temperature Class — The "High-Temperature Prevention Upper Limit" of Equipment

The temperature class corresponds to the maximum surface temperature of the equipment under normal and fault conditions, which must be lower than the ignition temperature of the explosive substances in the environment to avoid risks caused by high temperatures:

V. Authoritative Standards: Global Universal and China-Specific Safety Norms

The production and selection of explosion-proof air conditioners must comply with international and national authoritative standards to ensure compliance and safety:

1. International Standards:

• IEC 60079 Series (International Electrotechnical Commission): A globally universal standard for explosion-proof electrical equipment, covering safety requirements for different scenarios, such as IEC 60079-0 (basic requirements) and IEC 60079-1 (flameproof type requirements). It is the core compliance basis for exported products;

• NEMA 250/251/252 (National Electrical Manufacturers Association, USA): Targeting the North American market, it specifies the safety performance requirements of equipment in Zones 0, 1, and 2 (explosive gas environments), suitable for projects in the United States and North America.

2. Chinese Standards:

GB 3836 Series (China National Standard): A mandatory norm that domestic explosion-proof equipment must follow, such as GB 3836.1 (general requirements) and GB 3836.2 (flameproof type requirements). It covers different environments such as flammable gases and dust, and is a mandatory standard for domestic project selection.

VI. Winnex Air's Advantages in Rating Adaptation

Winnex Air's full range of explosion-proof air conditioners strictly complies with standards such as GB 3836 and IEC 60079, covering all ratings from Ex d IIB T4 to Ex d IIC T6. Customized solutions can be provided according to the "gas type + temperature environment + risk level" of the customer's scenario, ensuring that each piece of equipment accurately meets the needs. This not only avoids safety hazards caused by "insufficient rating" but also eliminates cost waste caused by "excessive rating".