Inspecting for bed bugs: which light for seams, joints and notes?

A technician kneeling at the edge of a stripped mattress, holding a hand lens over the seam while a headlamp lights it with a small pool of white light.

Inspecting for bed bugs? The seam is dark and both your hands are busy.

You look over the room, work along each accessible seam, look at the same joint from another angle, then write up what you found. The lens is in one hand and the seam or the pen is in the other.

Short answer

If the light your company issues already shows you the seam and leaves your hands free, keep it. If you are buying: the Nitecore HA23 UHE headlamp, which runs on three AAA batteries you can buy at any shop and gives 6 lumens two presses from off, and the EDC09 L-angle light to shine into a seam from the side.

See the kit ↓

The job at a glance

A visual inspection of accessible indoor furniture and rooms with a light, a hand lens and notes. Bed bugs are the documented example.

This guide does not cover diagnosis, treatment, chemicals, handling specimens, confined spaces (WSH Council advisory), hazardous areas, live electrical work or work at height. Reporting and PPE follow the NEA code of practice.

  • 6 lumensthe HA23 UHE’s lowest white setting, two presses from off
  • 3 x AAAin the box, and a flat set is replaced from any shop
  • Both handsthe lens in one, the seam or the pen in the other
  • 2 anglesthe headlamp straight on, the EDC09 L-angle light from the side

The job, in order

  1. Confirm the area and note the starting conditionYou see the room and what state it is in. The room light or your own light is on, and a notebook or phone is in your hand.
  2. Work along each accessible seamMattress piping and tags, bed frame, headboard, drawer joints, chair and sofa seams, skirting. You see the recessed edge of the seam. One hand holds the fabric and the other holds the light, which is the hand a headlamp frees.
  3. Look at the same joint from another angleOne hand holds the fabric open and a second light comes from the side, set down on its tail or on its clip.
  4. Use the hand lens and write notesYou see the seam through the lens and the notebook at reading distance, with the lens in one hand and the pen in the other.
  5. Describe what you foundYou write its appearance and where it is. A light does not tell you a room is infested.
  6. Finish, or the light dims or failsStop, record the unfinished area and carry on with a light that has its own battery.

Your job, step by step

This is our sequence from the NEA, Cornell and EPA guidance. Your company’s procedure comes first.

Look over the areaHeadlamp off
Room light on, notebook in handConfirm the area you are allowed to inspect and note the starting condition. Use the room light or your own light.
A technician standing at the foot of a stripped bed with the room light on, a notebook in one hand and the headlamp on their forehead switched off.
The seamLowest setting
Headlamp on the seam, lens closeDouble press Power from off for the 6 lumen setting (ULTRALOW) and point the headlamp where you look. Cornell’s guidance says to use a flashlight even if the area is well lit and to work systematically.
Gloved hands holding a mattress seam open with a hand lens above it, lit by a small pool of light from a headlamp.
Skirting and headboardLowest setting
Head low, light along the wallTilt your head so the beam runs along the skirting board and into the gap behind the headboard.
A technician crouched low looking along a skirting board beside a bed headboard, lit by a headlamp beam running along the wall.
A second angleHandheld on
Stand the EDC09 on its tailUse the low or middle setting. The head turns 102 degrees, so the light reaches the joint from the side while the headlamp lights it straight on. Stand the EDC09 on its tail or clip it on.
A small black L-angle light standing on its tail on a wooden bed frame with its head turned sideways to light a joint at the headboard.
Lens and notesLowest setting
Both hands busyTilt your head down so the headlamp lights the notebook or tablet. Cornell says to write down what you do and see.
A technician sitting on the edge of a stripped bed writing on a tablet, a headlamp tilted down onto the tablet and their hands.
Describe what you foundHeadlamp off
The service reportThe NEA code says the service report is issued at the end of every service visit.
Finish, or the light dims or failsHeadlamp off
Stop, record, carry onIf the HA23 UHE dims, change the three AAA batteries at the van.
Gloved hands putting three AAA batteries into an open headlamp at the back of a van, a box of loose batteries beside it.

How much runtime does your light need?

No source gives a length for this job, so we compare against one working day of 8 hours, our own assumption. A flat HA23 UHE is fixed with AAA batteries from any shop. The EDC09 charges by USB-C in the van.

our 8 h working day
One working day: 8 hours (our assumption)
HA23 UHE headlamp
HA23 UHE headlamp, 6 lumens (ULTRALOW)
HA23 UHE headlamp
HA23 UHE headlamp, 100 lumens (LOW)
HA23 UHE headlamp
HA23 UHE headlamp, 280 lumens (MID)
EDC09 L-angle light
EDC09 L-angle light, low setting (40 lumens)
EDC09 L-angle light
EDC09 L-angle light, middle setting (180 lumens)

Each bar is one set of batteries on that setting. The EDC09 figures are at 26°C. The light gets dimmer as the batteries drain. You use the low settings at arm’s length.

How close you need to see

First-person view of a mattress seam at arm's length, a gloved hand holding a hand lens, the seam lit by a headlamp and a bedside table dim in the distance. Through the lens: the seam itself Arm’s length: the piping and joints Across the room: the next piece of furniture

Illustration, not a measured beam pattern.

What the beam gives you

The HA23 UHE has a flood beam: four emitters behind one faceted lens, spread over more than 100 degrees. At arm’s length it lights the seam and the fabric around it, and it cannot be focused to a spot.

The 14 m beam distance on the 6 lumen setting is where the beam fades to moonlight level, about three car lengths. On the 100 lumen setting it is 54 m, about an 18 storey HDB block. Both are far more than a bedroom needs, so the near part of the beam is what counts.

Colour comes with the MODE button: neutral white (4,500 K), warm (3,000 K) or cool (6,500 K). The EDC09 has the same three. Its colour rendering (CRI) is 83 in neutral, 97 in warm and 73 in cool.

If the battery runs down, or the lamp fails

Battery runs down

Change the three AAA batteries in the HA23 UHE. Keep a spare set in the van. The EDC09 charges by USB-C.

Lamp fails or gets lost

A second light with its own battery: the EDC09, or a torch you own. It takes a hand, so stop, record the unfinished area, then carry on.

Practical checklist

  • Pack a spare set of 3 AAA batteries, alkaline or Ni-MH. 10400 LFP and Li-ion cells do not work in the HA23 UHE.
  • Charge the EDC09 by USB-C in the van. It takes about 1h20 on a 5 V/2 A adapter and works while charging.
  • Lock the HA23 UHE in your bag: from off, hold both buttons for 2 seconds until it flashes 3 times. Changing the batteries unlocks it.
  • Switch the EDC09 off at the tail by sliding the switch to the end position. We have no lockout procedure to give for it.
  • Check the HA23 UHE battery level: from off, short press MODE and the power level shows for 2 seconds.
  • Keep the second light in a different pocket from the headlamp.

The kit we’d pack

HA23 UHE headlamp
Main light, on your head
HA23 UHE headlamp
S$69
  • 6 lumens white straight from off, with a double press on Power
  • Runs on 3 AAA batteries, included. Replace them with alkaline or Ni-MH AAA from any shop
  • About 97 hours on the 6 lumen setting and 8 hours on the 100 lumen setting
  • A wide flood beam, with neutral, warm or cool white
  • 90 g with batteries and headband. Headband and clip included
View product →
EDC09 L-angle light
Second light, from the side
EDC09 L-angle light
S$109
  • The head turns 102 degrees. Stand it on its tail or clip it on
  • Use the low setting (40 lumens, 13 hours) or the middle setting (180 lumens, 2h45)
  • The 1,600 lumens in the name is the cool white high setting, which runs 2h15
  • Charges by USB-C in about 1h20. 114 g
View product →
Headlamp and L-angle light S$178

The spare is a set of AAA batteries from any shop, and it covers a flat battery only. If you want a rechargeable pack for the HA23 UHE, the HLB1500 (S$19) is below.

Already own a light? Check it against this list.

  • It leaves both hands free, or you can set it down so it stays aimed.
  • It has a low setting you can reach from off.
  • You can light a seam from the side as well as straight on.
  • You can replace or charge its battery between calls.
  • You have a second light with its own battery.
  • Your employer accepts it on site.

Other lights and a battery option

NU25 MCT UL headlamp
47 g, rechargeable
NU25 MCT UL headlamp
  • 6 lumens white from off with a double press on Power, the same as the HA23 UHE. About 45 hours on that setting.
  • Built-in battery, charges by USB-C. There is no spare cell, so you recharge it when it runs down.
S$79
View headlamp →
HC65 UHE headlamp
Brighter, swappable 18650
HC65 UHE headlamp
  • Takes a swappable 18650 battery, and one (4,000 mAh) is included. About 31 hours on the 100 lumen middle setting.
  • Heavier, at 152 g with battery and headband.
S$179
View headlamp →
HLB1500 battery pack
Rechargeable pack for the HA23
HLB1500 battery pack
  • Takes the place of the AAA batteries in the HA23 UHE and charges by USB-C. About 12 hours on the 100 lumen setting, against 8 hours on AAA.
  • The HA23 UHE also runs on 3 AAA batteries if the pack goes flat.
S$19
View battery pack →

Runtimes are for the setting and battery listed. We do not list a UV light here: there is no documented inspection workflow for it in our sources.

What the guidance says

These are guidance pages, not endorsements of any product. None of them mentions Nitecore.

Questions

Why AAA batteries?

A flat set is replaced with alkaline or Ni-MH AAA batteries from any shop, and changing the batteries unlocks the lamp if you had locked it. Three alkaline AAA come in the box. The HA23 UHE does not work on 10400 LFP or 10400 Li-ion cells. If you would rather recharge, the HLB1500 battery pack (S$19) takes their place and charges by USB-C.

Which setting for a seam?

Start with the 6 lumen setting (ULTRALOW) up close: double press the Power button from off. Use the 100 lumen setting (LOW) for the room: hold Power for one second from off. No source gives a minimum brightness for this job, so use the lowest setting that shows you the seam clearly.

Can I use my phone torch?

The lens in one hand and the seam or the pen in the other leave no hand for a phone. A headlamp leaves both free.

Do I need a UV light?

We do not list a UV light here. There is no documented inspection workflow for it in our sources. No light on this page identifies a pest or tells you a room is infested.

Is this light certified for hazardous areas?

No. None of the lights on this page is certified for explosive atmospheres. The HA23 UHE and EDC09 manuals both say not to use the light to illuminate flammable or explosive materials. A waterproof rating (IP68 on the HA23 UHE, IPX6 on the EDC09) does not clear a light for a site. This guide does not cover hazardous areas or confined spaces.

My company issues a torch. Do I need this?

Not if it shows you the seam and leaves your hands free. Your employer’s accepted equipment comes first. A handheld torch takes one hand, so check it against the list in the kit section.

What does this guide not cover?

Diagnosis or identification, treatment, chemicals and pesticides, handling or collecting live specimens, confined spaces and crawlspaces, hazardous areas, dismantling electrical sockets, live electrical work and work at height. Identification, treatment and reporting follow the NEA code of practice and your company’s procedures.

Questions about your own gear? Contact the team.

Sources and credits

  1. NEA, Management of Bed Bugs: visual inspection of furniture, engaging a pest management company. nea.gov.sg
  2. NEA, Code of Practice for Vector Control Operator, Technician and Worker, 2nd edition, 5 April 2023: service report, workplace safety, PPE. nea.gov.sg
  3. WSH Council, Technical Advisory on Working Safely in Confined Spaces, 2010: why confined spaces are outside this guide. tal.sg
  4. Cornell CALS Integrated Pest Management, Bed Bug FAQs: flashlight, hand lens, notes. cals.cornell.edu
  5. US EPA, How to Find Bed Bugs: where to look. epa.gov
  6. Nitecore, HA23 UHE user manual: settings, runtimes, controls, lockout. nitecore.com
  7. Nitecore, EDC09 user manual: settings, runtimes, rotating head, charging. nitecore.com
  8. Nitecore, NU25 MCT user manual. nitecore.com
  9. Nitecore, HC65 UHE user manual. nitecore.com
  10. Nitecore Singapore, product prices and stock, 6 October 2026. nitecore.sg

This is a buying guide for lights, not pest control guidance. Identification, treatment and reporting follow the NEA code of practice and your company’s procedures. None of these lights is certified for hazardous atmospheres.

Scene illustrations on this page were created for this guide and do not show a specific site or person.

Last reviewed 6 October 2026.