Electric fly killers (EFKs) use ultraviolet light to attract and then electrocute or trap flying insects, while sticky fly traps use adhesive surfaces — with or without UV attractants — to catch and retain them. For most indoor environments, UV-based electric fly killers with integrated glue boards offer superior catch rates and more discreet operation than standalone sticky traps.
Key Takeaways
- Electric fly killers with UV lamps attract insects from up to 15 metres away; most passive sticky strips attract from less than 1 metre.
- Glue board-style EFKs retain insects silently and hygienically, making them the preferred choice in food-handling environments under UK Food Standards Agency guidance.
- Sticky fly traps cost as little as £1–£3 per unit; commercial EFKs range from £80 to £600+, but cover significantly larger areas per unit.
- UV lamp output degrades by roughly 60% after 8,000 hours of use — lamps should be replaced annually even when they still appear to glow.
- Flyscreens used alongside either device reduce incoming insect pressure, improving the effectiveness of whichever trap is deployed.
What Is an Electric Fly Killer?
An electric fly killer is a wall- or ceiling-mounted device that emits UV-A light at wavelengths of 320–400 nm to draw flying insects towards it. Once attracted, the insect is either killed by a high-voltage electrocuting grid or retained on a replaceable adhesive board. The fly light trap category covers both electrocuting and glue board variants, and the correct choice depends on the setting.
Electrocuting EFKs (often called “zapper” types) produce an audible crack on contact and can disperse insect fragments — making them unsuitable in open food preparation areas. Glue board EFKs contain the insect intact and are the standard recommendation for kitchens, food retail, and healthcare settings.
What Is a Sticky Fly Trap?
A sticky fly trap is any device that uses an adhesive surface to capture flying insects on contact. The category includes hanging spiral strips, window-mounted clear panels, and baited flat boards. Some sticky traps include a pheromone or food-based attractant; most rely on the insect making incidental contact.
Passive sticky strips have no active attractant and depend on high insect traffic near the trap. Their catch rate is adequate in very small spaces — a domestic kitchen or a garden shed — but they scale poorly to larger or busier premises.
| Feature | Electric Fly Killer (EFK) | Sticky Fly Trap |
|---|---|---|
| Attraction range | Up to 15 metres (UV-A light) | Under 1 metre (passive types) |
| Best for | Commercial kitchens, food retail, healthcare, offices | Domestic use, small rooms, supplementary control |
| Typical cost | £80–£600+ per unit | £1–£15 per unit or pack |
| Running cost | Electricity + annual lamp replacement | Replacement boards or strips every 4–12 weeks |
| Hygiene rating | High (glue board models contain insects intact) | Moderate (exposed adhesive can accumulate debris) |
| Noise | Silent (glue board) or audible crack (zapper) | Silent |
| Limitation | Higher upfront cost; requires mains power | Low attraction range; fills quickly in high-pest areas |
Which Device Works Better in Food Environments?
Glue board EFKs are the correct choice in any food-handling environment. They contain captured insects within a sealed board, preventing contamination of surfaces or product. UK pest control practitioners — including teams at Pelsis Pro — consistently observe that glue board EFKs placed at entry points and near light sources reduce flying insect counts more reliably than sticky strips alone.
Electrocuting EFKs must not operate directly above exposed food or food contact surfaces. They can scatter insect fragments and increase the risk of contamination.
Avoid using sticky strips as the primary solution in commercial kitchens. Their limited attraction range means they often miss insects that never pass through the trap zone.
When Does a Sticky Trap Outperform an EFK?
Sticky traps have a clear advantage in situations where mains electricity is unavailable, where noise is a concern, or where cost is a primary constraint. A clear window-mounted sticky panel in a domestic setting can intercept flies drawn to light without any running cost. In these low-pressure environments, the limited attraction range is not a meaningful drawback.
Sticky traps also act as useful monitoring tools in an integrated pest management (IPM) programme. By counting and identifying captured insects on a weekly basis, a pest controller can assess species, peak activity periods, and likely entry routes — information that informs wider control decisions.
How to Choose the Right Device for Your Setting
- Identify the environment. Food-handling or healthcare premises require a glue board EFK as a minimum. Use sticky traps in domestic or low-traffic spaces.
- Measure the area. One commercial EFK typically covers 30–80 m² depending on the model. Calculate coverage before purchasing.
- Position the device correctly. Install EFKs 2–3 metres above floor level. Position them away from competing light sources and close to known entry points. Do not position them directly above food preparation surfaces.
- Add exclusion measures. Fit flyscreens to windows and doors to reduce incoming insect pressure and improve trap efficiency.
- Service regularly. Replace EFK UV lamps annually and glue boards every 4–8 weeks. Replace sticky strips as soon as the adhesive surface is more than 50% covered.
Frequently Asked Questions
Do electric fly killers work better than sticky traps?
In most commercial and semi-commercial settings, UV-based electric fly killers catch significantly more insects than passive sticky traps because they actively attract flies from up to 15 metres away. Sticky traps are more cost-effective for small domestic spaces with low insect pressure.
Are sticky fly traps safe to use in kitchens?
You can safely use sticky traps in kitchens if you position them away from open food and food contact surfaces. They are not, however, the recommended primary control device in commercial food environments, where glue board EFKs are the standard.
How often should EFK glue boards be replaced?
Maintenance staff should replace glue boards in electric fly killers every four to eight weeks. They should replace them sooner if insects heavily cover the adhesive surface. In high-pest-pressure environments such as commercial kitchens in summer, monthly replacement is a minimum standard.
Why do UV lamps in EFKs need annual replacement?
UV-A output from fluorescent fly killer lamps degrades significantly with use — by approximately 60% after 8,000 hours — even though the lamp continues to emit visible light. An EFK running on a degraded lamp attracts far fewer insects and provides inadequate control.
Can sticky traps be used alongside an EFK?
Yes. Sticky traps used as monitoring devices alongside a primary EFK installation provide useful data on insect species and activity levels without interfering with the EFK’s function. Pelsis Pro recommends this combined approach for IPM programmes that require detailed pest records.
What is the most important factor in positioning an electric fly killer?
Distance from competing light sources and proximity to entry points are the two critical placement factors. An EFK positioned near a bright window will lose much of its attractant advantage; one placed close to a door, loading bay, or ventilation opening intercepts insects before they disperse into the premises.