TempoLife › Features › Defibrillators and cardiac arrest response › wet-and-metal
Rain, snow, metal and a pool deck
The environmental worries that stop bystanders using a defibrillator, answered one at a time: standing water, a steel floor, a wet chest, a moving vehicle, snow, and whether you can be shocked yourself.
CPR in sixty seconds
- Unresponsive and not breathing normally? Gasping is not breathing. Treat it as a cardiac arrest.
- Call 112 (113 in Norway). Speaker on, phone on the floor. Stay on the line — the dispatcher will coach you.
- Push hard and fast in the centre of the chest: 5–6 cm in an adult, 100–120 per minute, letting the chest come all the way back up.
- Send somebody else for a defibrillator. Do not go yourself unless it is seconds away. Keep compressing.
- Turn the device on and do what it says. It decides whether to shock. After a shock, go straight back to compressions.
This is a reference written for bystanders, not a diagnosis, a training course or medical advice. It cannot tell you what is wrong with a particular person, and it does not replace the dispatcher on the other end of an emergency call — they can see what is near you and they will talk you through it. If you are worried about your own heart, or about a symptom, that is a conversation with a clinician rather than a page on a website.
What actually conducts
The shock travels between the two pads through the chest. Anything that offers an easier route across the outside of the body — a film of water on the skin, sweat, snow melting on the chest — steals current from the heart and can burn the skin. Anything that connects you to the patient can pass a fraction of the current to you. Those two ideas cover every situation below, and neither of them is a reason to leave the device in its cabinet.
Rain and snow
Defibrillation in the rain is safe and is done routinely. Do not delay while looking for shelter. Dry the chest at the pad sites with whatever is to hand, apply the pads firmly, and shield the chest with a coat or an umbrella held by somebody else if that costs no time. Falling snow behaves the same way once it melts on warm skin: wipe, apply, shock. Cold pads stick less well, so press each one down properly rather than laying it on.
Standing water and wet floors
A person lying in a puddle, on a flooded floor or at the edge of a pool should be dragged clear of the water if you can do it in a few seconds — that is about the rescuers as much as the patient. If they cannot be moved, dry the chest, make sure nobody is kneeling in the water while the shock is delivered, and go ahead. Damp ground under a normally dressed rescuer is not a documented hazard; a rescuer with their knees in a pool touching the patient is a different matter.
Metal floors, gratings and vehicles
Steel decks, gym platforms, boat gratings and industrial gantries make people hesitate. The guidance is that a metal surface is not a contraindication: keep the pads well apart, make sure they are not touching metal, and make sure no rescuer is touching the patient during the shock. If moving the person onto a non-conducting surface takes a few seconds, do it. If it takes a minute, do not. In a moving vehicle, train or aircraft, stop the vehicle or accept the movement — analysis is unreliable while the patient is being jostled, so hold still during the analysis prompt.
Can the rescuer be shocked?
Injury to bystanders from public-access defibrillation is very rare, and essentially all documented cases involve somebody in physical contact with the patient at the moment of discharge. That is exactly what the machine's "stand clear" prompt is for. Shout it, look along the whole body — feet included, and check nobody is holding a hand or leaning on a stretcher — and only then press the button. Modern practice minimises pre-shock pauses, so make the check fast and habitual rather than long.
| Situation | Real risk | What to do |
|---|---|---|
| Rain or falling snow | Low | Dry the pad sites; do not wait for shelter |
| Wet chest (pool, sweat, sea) | Moderate — current tracks across skin | Wipe the chest dry, then apply pads |
| Lying in standing water | Moderate — for the rescuers | Drag clear if quick; keep everyone out of the water at shock |
| Metal floor or grating | Low | Keep pads apart and off metal; nobody touching at shock |
| Moving vehicle or vessel | Analysis unreliable | Hold still or stop the vehicle during analysis |
| Oxygen cylinder or flammable vapour nearby | Fire risk | Move the source or the patient a few metres away |
Sources: European Resuscitation Council Guidelines · checked 2026-09-08
Frequently asked questions
Is it safe to defibrillate someone in the rain?
Yes, and it is done routinely. Dry the two pad sites, press the pads on firmly and follow the device. Delaying to find shelter costs far more than the rain does.
Do I have to move someone off a metal floor?
Only if it is quick. Metal is not a contraindication. Keep the pads apart and off the metal, and make sure nobody is touching the patient at the moment of the shock.
Can I be shocked while doing compressions?
Only if you are touching the patient when the shock is delivered, which is what the "stand clear" prompt prevents. Injuries to rescuers are very rare.
What to do, right now
Is this a cardiac arrest?
Two checks decide it: not responding, and not breathing normally. The noisy gasping that fools nearly everyone, why a brief seizure at the start is a cardiac sign, and why a heart attack is a different emergency.
Hands-only CPR, in sixty seconds
Centre of the chest, 100 to 120 pushes a minute, 5 to 6 cm deep, let the chest come all the way back up, and do not stop. The rate, the depth, the fatigue problem, and a pacer that keeps you on the beat.
The emergency call, and the address problem
What the dispatcher asks, why the phone goes on speaker on the floor, how dispatcher-guided CPR works, and the single hardest question in a rural arrest: where exactly are you?
Using a defibrillator, step by step
Open it, turn it on, bare the chest, follow the voice. What the machine decides for you, what it will never do, and the one instruction people get wrong — go straight back to compressions after the shock.
Where the pads go, and what gets in the way
Right collarbone and left ribs, or front and back. Chest hair, sweat, snow, a medicine patch, a pacemaker lump, an underwired bra, a tattoo: which of these actually matter and what to do about each.
Everything on this subject
Before the emergency, there is a long quiet stretch
Blood pressure, resting heart rate, movement and sleep are the part of this you can act on for years beforehand. TempoLife keeps them in one place, free to start.