For previous reading, please refer to Deciphering Plastic Property Charts (Part 10) | Weather Resistance + Chemical Properties: Key Factor.
Small appliances (electric kettles, air fryers, coffee makers, food processors, etc.) often involve electrically powered and heating components. If flame retardancy of plastic parts is substandard, they are prone to ignition and spread when exposed to high temperatures, short circuits, or open flames. This can not only burn product but also cause safety accidents and fail to meet national 3C mandatory certification requirements.
Today, we focus on small appliance scenario, breaking down definition of plastic flame retardant performance, flame retardant levels (national standards + industry-standards), and material selection standards for key components of small appliances. We provide simple diagrams for intuitive understanding, balancing compliance and practicality, allowing even beginners to quickly implement solutions!

1. Core Meaning of Flame Retardant Performance
Flame retardant performance of plastics refers to material's ability to inhibit combustion when in contact with a fire source, to quickly self-extinguish after leaving fire source, and to prevent spread of flames. Core is not "non-combustible," but rather "difficult to burn, non-spreading, and risk-reducing." For small household appliances: Internal plastic components near heating element and circuit board must "not ignite at high temperatures, and if ignited, extinguish quickly without igniting surrounding components."
2. Hazards of Flame Retardant Failure in Small Household Appliances (Must Be Avoided)
- Direct Risks: Short circuits, overheating of heating components igniting plastic, rapid flame spread, causing fires and electric shocks;
- Compliance Risks: Failure to comply with GB 4706.1 (National Standard for Safety of Small Household Appliances), resulting in 3C certification failure and prohibition from market sales;
- After-Sales Risks: Causing safety accidents, resulting in liability for compensation and damage to brand reputation.

 

Flame retardancy of plastic components in small household appliances must simultaneously meet national mandatory safety standards and industry flame retardant rating standards. A combination of both is basis for compliant material selection.
1. Mandatory Standard: GB 4706.1 "Safety of Household and Similar Electrical Appliances - Part 1: General Requirements"
This is "safety pass" for small household appliances, with core requirements for flame retardancy of plastic parts:
- Plastic parts surrounding heating components (e.g., electric kettle bases, air fryer inner liner supports): must be self-extinguishing, quickly extinguishing after flame is applied and removed from heat source;
- Outer shell/non-heating surrounding plastic parts: must be flame-retardant, not easily ignited, and prevent spread of flame;
- Core principle: All plastic parts related to electricity and heat must pass "glow wire test" and "needle flame test" in standard for flame retardancy.
2. Industry-standard flame retardant rating: UL94 standard (most commonly used, compatible with national standards)
For small household appliances, prioritize UL94 flame retardant rating. Higher ratings indicate better flame retardancy. Core ratings are divided into four categories from lowest to highest. Commonly used in small appliances are V-2, V-1, and V-0 (V-0/V-1 preferred). For special high-temperature components, VTM-0 (for thin-walled parts) can be selected. Rating definitions are clear and unambiguous:
- UL94 V-0 (highest, preferred for core components in small appliances): When sample is burned vertically, each ignition lasts 10 seconds. After two ignitions, it self-extinguishes within 10 seconds of being removed from flame source, with no molten droplets igniting cotton below, and no flame spread.
- UL94 V-1 (second highest, secondary core components in small appliances): After two ignitions, it self-extinguishes within 30 seconds of being removed from flame source, with no molten droplets igniting cotton below, and no flame spread.
- UL94 V-2 (Basic Grade, Non-Heating Peripheral Components): Self-extinguishing within ≤30 seconds after removal from flame source after two ignitions; molten droplets are permissible, but these droplets will not ignite absorbent cotton.
- Unrated (HB Grade): Only capable of slow burning; no self-extinguishing properties; strictly prohibited for use in any electrical or heat-related components of small appliances.

 

Different components in small appliances have different heating risks and safety requirements. Flame retardant grade selection must be precisely matched. Combining commonly used plastics with flame retardant modification schemes, a core component material selection table has been compiled for direct application, while also considering mechanical properties and heat resistance (adapting to previously mentioned HDT and long-term operating temperature).
Flame-retardant Material Selection Guide for Core Components of Small Home Appliances (Compatible with 3C Certification)
Small Home Appliance Component Type | Heating Risk | Recommended UL94 Flame Retardant Rating | Commonly Used Plastics + Flame Retardant Modification Scheme | Core Requirements (Performance Consideration)
Heating Plate Base, Heating Element Bracket (Electric Kettle/Coffee Machine) | Extremely High V-0 | Flame Retardant Glass Fiber Reinforced PP (30%), Flame Retardant PC | Flame Retardant V-0 + HDT≥120℃ + High Rigidity, High Temperature Resistance and No Deformation
Circuit Board Shell, Terminal Block (All Small Home Appliances) | Extremely High V-0 | Flame Retardant ABS, Flame Retardant PC/ABS Alloy | Flame Retardant V-0 + Good Insulation, Compatible with Electrical Components
Air Fryer Inner Pot, Air Duct Bracket (High Temperature Hot Air Zone) | High V-0 | Flame Retardant Glass Fiber Reinforced PC, Flame Retardant PPS | Flame Retardant V-0 + Long-Term Use Temperature ≥90℃, High Temperature Aging Resistance
Electric Kettle Body, Blender Cup (Near Heat Source) | Medium V-1 Flame-retardant and heat-resistant PP, flame-retardant PC: Flame-retardant V-1 + boiling water resistant (food grade requires GB4806.7), safe and non-toxic.
Small appliance shells and handles (non-direct heat-generating areas): Low V-2/V-1, ordinary flame-retardant ABS, flame-retardant PP. Flame-retardant compliance + consideration of appearance and impact resistance, reducing costs.
Decorative parts and non-load-bearing components (no heat generation risk): Extremely low V-2 (or basic flame retardant). Flame-retardant PS, flame-retardant PP. Flame-retardant compliance is sufficient, cost control is priority.
Core Principles:
1. Direct contact heat-generating/electrical components: V-0 grade is mandatory, glass fiber reinforced flame-retardant is preferred (considering rigidity and heat resistance);
2. Food contact components (e.g., kettle body, cup body): Select "flame-retardant + food-grade" modified materials, must comply with GB4806.7, toxic flame retardants are prohibited;
3. Non-critical components such as shells: V-1/V-2 is optional, balancing performance and cost.

✅ Tip 1: Prioritize UL94 V-0/V-1 Flame Retardant Ratings, and Ensure Compliance with Glow Wire Test
Passing "glow wire test" (simulating ignition of plastic by overheated components) is a core requirement for 3C certification of small appliances. Simply meeting UL94 rating is insufficient; material must pass glow wire temperature (typically 850℃) specified in GB 4706.1.
✅ Tip 2: Choose "Environmentally Friendly and Non-Toxic Flame Retardants" for Food Contact Components
Food contact components such as kettle body and inner liner must use halogen-free flame retardants (such as phosphorus-based flame retardants). Use of toxic flame retardants containing halogens or heavy metals is prohibited, and appliance must be labeled as compliant with GB 4806.7.
✅ Tip 3: Flame Retardant Modification Must Consider Heat Resistance to Avoid High-Temperature Failure
For components near heat sources, flame retardant materials must simultaneously meet standards for both flame retardant rating and thermal performance. For example, flame-retardant PP requires heat-resistant modification to ensure HDT ≥ 120℃, preventing a decrease in flame retardant performance after softening at high temperatures.
✅ Tip 4: Choose "High Flame Retardant Efficiency Materials" for Thin-Walled Components
Flame retardant efficiency of thin-walled components (wall thickness ≤ 1.5mm) will decrease. Prioritize PC/ABS alloys and flame-retardant PC. These materials can maintain a V-0 rating even with thin walls, avoiding flame retardant failure due to insufficient wall thickness.
✅ Tip 5: Reject "Fake Flame Retardant Materials" and Request Test Reports
When selecting materials, request a flame retardant rating test report (UL94) + GB 4706.1 compatibility report from supplier to confirm reports are authentic and valid, avoiding purchase of fake flame retardant materials that contain only a small amount of added flame retardant or do not meet standards.
✅ Tip 6: Manufacturing Process Does Not Affect Flame Retardant Performance
No need to deliberately adjust temperature during injection molding (follow material's standard process), but material degradation (due to excessively high temperatures) must be avoided, otherwise flame retardant will become ineffective, reducing flame retardant rating.

❌ Misconception 1: Believing that "Flame retardant means non-combustible"
Core of flame retardant properties is "difficult to burn, self-extinguishing, and non-spreading," not absolute non-combustibility. Prolonged exposure to high-temperature open flame will still cause carbonization. The key is whether it can quickly self-extinguish after flame is removed.
❌ Misconception 2: Choosing V-0 for all components is a waste of cost
For non-heating, non-electrical peripheral casings and decorative parts, V-1/V-2 is sufficient. There's no need to pursue V-0; excessive material selection will increase costs.
❌ Myth 3: Focusing solely on flame retardancy rating while ignoring heat resistance
For example, flame-retardant ABS may achieve a V-0 flame retardancy rating, but its HDT (Heat Temperature) is only 80℃. Using it in an electric kettle base (a heat source near 100℃) will cause it to soften and deform, rendering its flame retardancy ineffective. Both heat resistance and flame retardancy must meet standards.
❌ Myth 4: Using halogenated flame retardants for food contact parts
Halogenated flame retardants release toxic gases upon combustion and may migrate into food, violating GB 4806.7. Halogen-free, environmentally friendly flame retardants must be selected.
❌ Myth 5: Selecting materials based on experience without conducting compliance testing
Even if a flame retardant is selected, 3C certification-related tests (glow wire and needle flame tests) are still required before mass production to avoid batch variations leading to substandard flame retardancy.

For small household appliances, flame retardancy is not a "bonus," but a compliance baseline and a safety red line, directly affecting whether product can be marketed and user safety.
Remember core logic: determine flame retardant level based on heat risk of component (V-0 for core heat-generating components, V-1/V-2 for non-core components), take into account both heat resistance and compliance (GB4706.1 + 3C certification), add non-toxic and environmentally friendly controls for food contact components. This will enable precise material selection, avoid safety and compliance risks.