After the hunt
Metal Detecting Safety and Utilities: Before You Disturb Any Ground
Quick answer
Contact the appropriate utility location service before disturbing ground. Never touch suspected ordnance or ammunition: mark it, move away and call the police. If you uncover human remains, stop immediately, do not disturb anything further, and contact the police and the heritage authority. Wear gloves, because buried glass and rusted metal are the routine injury.
Most detecting hazards are boring and preventable: cuts from buried glass, a turned ankle in an open hole, sunburn, dehydration, ticks. Three are not boring at all, and they are the reason this page exists. Buried utilities can be struck by a hand digger. Old ordnance and ammunition come out of ground across most of the world and are dangerous decades later. And human remains turn up more often than newcomers expect, in circumstances where the right response is legal as much as practical.
Everything below is the standard advice published by the national detecting associations and by utility safety bodies. None of it is complicated. All of it is the sort of thing people skip because it has never happened to them yet.
Top pick
Serious Detecting Gloves (large)
Broken glass and rusted metal are what actually comes out of old ground, and padded gloves with touchscreen fingertips are the cheapest injury prevention available.
Price was accurate when this page was compiled and changes often.
On this page
What do you do before disturbing ground?
Contact the appropriate utility location service before you dig, on any site where you do not have certain knowledge of what is buried. Most countries operate a free service that will mark the approximate position of buried electricity, gas, water and telecommunications lines, and in many places contacting it before ground disturbance is a legal requirement rather than a courtesy. Allow the lead time the service specifies, which is usually several working days.
This matters more than detectorists assume because the depths involved are shallower than people think. Service drops to outbuildings, garden lighting cables, irrigation lines and older shallow-laid utilities can sit within the range of an ordinary hand digger, especially where ground has eroded or been regraded. A detector will sing over all of them. Treat any long, strong, linear signal as a service until proved otherwise, and do not dig it.
Which hazards actually come up, and what do you do?
The middle column is the immediate action. Where it says stop and call, that means stop detecting in the area entirely, not finish the hole first.
Three hazards require you to stop and call somebody rather than handle them yourself: suspected ordnance or ammunition, human remains, and any strike on or exposure of a buried utility.
| Hazard | What to do | What never to do |
|---|---|---|
| Suspected ordnance, shell or munition | Stop, do not touch it, note the position, move away and call the police | Lift it, move it, put it in the car or take it home |
| Ammunition or cartridges of any age | Leave it in place and report it to the police | Pocket it as a souvenir |
| Human remains | Stop immediately, disturb nothing further, contact the police and the heritage authority | Continue digging, photograph and publish, or remove anything |
| Buried utility line exposed or struck | Stop, move away, call the utility emergency number | Attempt to inspect, move or cover it yourself |
| Long strong linear signal | Treat it as a service and leave it | Dig to find out what it is |
| Buried glass and rusted metal | Gloves on, lift carefully, carry it out in the trash compartment | Sweep the hole with bare fingers |
| Open holes on site | Fill each one before moving on | Leave a hole open while you chase the next signal |
| Tides and currents on a beach | Set a turnaround time, work with somebody present | Get cut off working a productive scour |
| Livestock in a field | Leave gates as found, keep distance, leave if stock is moved in | Cross a field with cattle to reach a signal |
| Ticks, heat and sun | Cover up, check afterwards, carry water | Assume a cool day means no exposure |
Emergency and utility contact numbers differ by country and region. Look up the correct ones for where you detect and save them before you need them.
Why is a long linear signal the one to leave alone?
Because buried services are long, continuous and strongly conductive, and they produce exactly the sort of loud confident signal that makes a detectorist reach for a digger. A coin gives a short response as the coil crosses it. A cable or a pipe gives a response that continues as you walk along it, and that continuity is the diagnostic. If a signal runs in a straight line for more than a couple of feet, stop and look at what is at each end of it: a meter, a pole, a building, a standpipe.
The same logic applies to anything running towards an outbuilding, a light fitting or a water trough. Learning to recognise the shape of these signals is part of reading the machine, which is covered in the signal guide, and it is one of the few cases where the correct response to a strong repeatable target is to walk away.
What should you carry?
Gloves, first. Serious Detecting Gloves (large) have padded palms and touchscreen fingertips, and they are what stands between your hand and the broken glass that comes out of every old house site. A Mini Waterproof First Aid Kit in the pouch or the car covers the cuts that are the routine injury in this hobby. NoCry Professional Gel Knee Pads prevent the slower damage, since you kneel for every single target.
A LHKNL Rechargeable LED Headlamp matters more than it sounds, because the last hole of the day is the one that gets filled badly in fading light, and backfilling properly needs both hands free. Carry water, tell somebody where you are going, and keep your phone charged. On beaches add the tide table, and read the saltwater guide for the water specific hazards, since coastal ground has a particular habit of producing military material.
What about the machine and the ground itself?
Low batteries change how a detector behaves before they stop it working, which matters for safety as well as finds: a machine behaving oddly on unfamiliar ground is a reason to stop and check rather than to push on. Rechargeable AA NiMH Batteries, 8 pack cells and a spare holder such as the Spare AA Battery Holder for Garrett Detectors make a battery change a two second job. Check the battery runtime calculator if you are planning a long session somewhere remote.
Ground itself is a hazard on derelict sites: unstable surfaces, old wells, capped shafts, collapsed cellars and contaminated fill are all common on exactly the sort of historic ground that looks appealing. Do not detect alone on a site like that, and do not assume an overgrown lot is safe because it is quiet. If the surface moves underfoot, leave.
Sources
- Published guidance from national utility location and damage prevention services
- Published codes of practice from national detecting associations
- Police and heritage authority guidance on reporting ordnance and human remains
- Manufacturer listings for the gloves, knee pads, headlamp and first aid kit named above
Frequently asked questions
Do I really need to call a utility location service before digging?
Yes, on any site where you do not have certain knowledge of what is buried. Most countries operate a free service that marks buried electricity, gas, water and telecommunications lines, and in many places contacting it before ground disturbance is a legal requirement. Allow the lead time it specifies, which is usually several working days, and treat any long linear signal as a service.
What do I do if I find something that looks like a shell or a bomb?
Do not touch it, do not move it and do not attempt to identify it. Mark the position, move away and call the police. Old ordnance remains dangerous for decades and has injured people who believed it was inert. This applies to ammunition and cartridges too, which should be left in place and reported rather than pocketed as a souvenir.
What if I uncover human remains?
Stop immediately, disturb nothing further, and contact the police. If the remains turn out to be archaeological rather than recent, the police will involve the heritage authority, but that judgement is not yours to make in the field. Do not continue detecting in that area, do not remove anything and do not photograph and publish what you have found.
How dangerous is detecting, realistically?
The common injuries are minor and preventable: cuts from buried glass and rusted metal, turned ankles in unfilled holes, sunburn and dehydration. Gloves, a small first aid kit, water and the habit of filling each hole before moving on handle nearly all of it. The serious hazards are rarer and specific, which is why ordnance, remains and utilities get their own responses.
Is it safe to detect alone?
On open familiar ground in daylight, generally yes, provided somebody knows where you are and your phone is charged. On derelict sites, in water, or anywhere with unstable surfaces, old wells or collapsed cellars, take somebody with you. Coastal work in particular should not be done alone, because cold water removes dexterity quickly and a rising tide makes decisions for you.
Researched, not professional advice. This page is compiled from published specifications, manuals and owner-review consensus, not hands-on testing. Target ID numbers, depth figures and settings vary with soil chemistry, moisture, target size, depth, orientation and firmware version, so treat every figure here as a starting point and verify it against your own machine's manual and your own ground. As an Amazon Associate we earn from qualifying purchases.