Company News | SEEKINGLED Explosion Proof Lighting

High-bay selection is not “pick something brighter” — it is decided by mounting height. A 4-metre workshop and a 10-metre hall are two different luminaires. The HB21 Series spans that whole range: 15 W to 300 W, flameproof Ex db IIC T6/T5 Gb, up to 150 lm/W and 45,000 lm at 300 W, IP67/IK10, C4 (ISO 12944) corrosion protection, and ATEX and IECEx certification. Typical duties: oil and gas processing buildings, offshore platform equipment decks, underground mines and tunnels, chemical and pharmaceutical halls, and large hangars and silos. The 200 W step replaces a 250 W metal-halide high bay — and the gas group is IIC (covering hydrogen and acetylene), where many competing high bays stop at IIB.

Step one: set the power by mounting height (a table you can hand to the designer)

Why not “one 300 W for everything”: at insufficient height, a big lamp gives you the illuminance but glare and a hard pool of light people have to work under, plus a wasted electricity bill. At excessive height, a small lamp never reaches the floor. Give us the mounting height, floor area and equipment obstruction layout and we will return the power step and the luminaire spacing directly.

Why group IIC matters specifically in halls

Gas groups rank by ignition difficulty: IIC → IIB → IIA. Group IIC covers hydrogen and acetylene — the two gases a petrochemical or chemical plant can least afford to ignore. Many competing explosion-proof high bays are certified IIB only, and unless the purchaser reads the marking character by character, it is easy to end up with two luminaires that look identical and are not. The HB21 marking reads Ex db IIC T6/T5 Gb.

The second point is the protection concept. A high bay’s job is to light a large volume from height inside Zone 1 — so it must be flameproof (the reasoning is set out in our FL7 Series article).

Mounting: adjustable bracket, ceiling and daisy-chain

• Adjustable U-bracket — the fitting aims and locks onto the equipment or work face without re-fabricating the bracket.
• Ceiling mounting — direct fixing to hall roofs and platform soffits.
• Daisy-chaining — several luminaires on one supply run, reducing entries and wiring points; combined with the BHD51 junction box, a whole floor of lighting becomes one system.

The housing provides 2 × Φ26 cable entries, supplied with 1 × M25×1.5 plug (304 stainless steel) and 1 × M25×1.5 gland (nickel-plated brass) for Φ9–16 mm cable; terminal capacity 1.5–4 mm².

Where the HB21 Series is installed

• Oil and gas production and processing buildings — gas processing and compressor halls, metering rooms; wide spans and high ceilings.
• Offshore platform equipment decks and modules — vibration, salt spray, no daylight.
• Underground mines and tunnels — continuous lighting with very short maintenance windows.
• Chemical and pharmaceutical halls — solvent vapour atmospheres where process equipment and signage must stay readable.
• Large stores, silos and hangars — spans above 10 metres covered by a small number of high-output fittings.
• Power plants, military facilities and paint shops — the general answer for high-hazard industrial halls.

What one HB21 200 W replaces

The maintenance cost of a high-bay position is never the lamp — it is the scaffolding, the permit and the lift. L80B20 >100,000 hours is what removes that line item from most halls entirely.

Specifications

Certification

The HB21 high-bay range carries ATEX and IECEx certification, marked II 2G Ex db IIC T6/T5 Gb (gas) and II 2D Ex tb IIIC T80 °C/T95 °C Db (dust), covering Zone 1 and 2 gas and Zone 21 and 22 dust. The certificate is tested across the full power ladder, and the published list is deliberately kept to the common SKUs so buyers have fewer variants to choose from — not because higher or lower steps are unavailable.

Before we quote — what we need from you

• Mounting height, floor area and obstruction layout — give us this and we will do the rest (power step and spacing).
• Zone and gas group — Zone 1 or 2; hydrogen or acetylene present; dust present.
• Ambient temperature on site — to confirm the temperature class.
• Mounting method — ceiling, bracket, or daisy-chained runs.
• Dimming — 0–10 V or PWM, if required.
• Quantity and destination — sample or bulk, and the destination port for a landed cost.

Frequently asked questions

How does a flameproof high bay differ from an ordinary LED high bay?
A flameproof high bay contains any internal explosion and cools the flame before it reaches the surrounding atmosphere, which is what makes it legal in Zone 1. An ordinary high bay carries no such certification — at the moment gas is released, the fitting itself becomes an ignition source. No price discount fixes that, and hazardous-area projects will not accept it.

Does it have an emergency function?
No built-in emergency supply; an external emergency power kit can be fitted where the project requires it.

What is the IP rating?
IP67 and IK10 with C4 (ISO 12944) corrosion protection — dust-tight, resistant to driving rain and jets, 20-joule impact rating, and suited to corrosive industrial atmospheres.

What is the MOQ and lead time?
Standard MOQ is 100 pieces; early-stage orders can start with samples or small lots. Samples take about 10–14 days and bulk orders 3–4 weeks. The product carries a 5-year warranty.

Downloads

Download the HB21 High Bay datasheet →

Related products

For the portable and maintenance-duty version of the same series, see the HB21 work light (also Ex db IIC, with a 24 V DC version). Wide-area floodlighting: the FL7 Series in Zone 1 and the FL8 Series in Zone 2. Linear walkway and pipe-rack lighting: the LO Series and the Bay51 Series. Cable terminations: the BHD51 junction box.