Reading the Beach: Flags, Rips and Swimming with Confidence — from Cornwall to California to Copacabana

The best beach days start with a little knowledge. Whether you’re on a lifeguarded beach in Cornwall, in Florida or California, or stepping onto the sand at Ipanema, knowing how to read the beach means you can relax and enjoy the water — and know exactly what to do if conditions change.

Please note: this is general guidance to help you feel confident, not a substitute for local advice. Conditions change by the hour. Always follow the lifeguards, signs and flags on the beach you’re visiting.

In the UK: know your flags

On lifeguarded beaches in the UK, the RNLI uses a simple set of flags:

• Red and yellow — the lifeguarded area. This is the safest place to swim and bodyboard. Surfboards, paddleboards and kayaks stay outside it.
• Red — danger. Do not enter the water.
• Black and white chequered — the zone for surfboards and other non-powered craft. Don’t swim or bodyboard here.
• Orange windsock — offshore or strong winds. Don’t use inflatables in the water.

In the USA: a hazard scale, set locally

Most lifeguarded beaches in the United States follow flag guidelines from the United States Lifesaving Association (USLA). Here the colours describe the level of hazard in the water:

• Double red — the water is closed to the public. Don’t go in.
• Red — high hazard: strong surf and/or currents. Everyone is discouraged from entering the water, and anyone who does should take great care.
• Yellow — medium hazard: moderate surf and/or currents. Weak swimmers should stay out; everyone else, be cautious.
• Purple — marine pests such as jellyfish or stingrays are in the water. (It doesn’t mean sharks.)
• Red and yellow — the lifeguard-supervised swimming area, just as in the UK.
• Red and white (quartered) — emergency evacuation. Leave the water.

You may also see a green flag on some beaches for calmer conditions — but the USLA deliberately doesn’t use one, because there is always some hazard in the ocean. Flag use is a local decision, so systems vary from state to state and beach to beach. Read the signs at the entrance, which explain the local flags, and remember that no flag doesn’t mean safe water — it may simply mean there’s no lifeguard on duty.

In Brazil: the colours tell you the risk

Brazilian beaches are patrolled by lifeguards (guarda-vidas) from each state’s fire brigade, the Corpo de Bombeiros. In Rio de Janeiro, flags generally signal the level of risk:

• Green — lower risk, calmer water.
• Yellow — medium risk. Take care, and weaker swimmers shouldn’t go in alone.
• Red — high risk. Stay out of the water.
• Purple or lilac — marine animals, such as jellyfish, have been seen.

Systems vary slightly between states, and you may also see small red flags or metal plates on the sand marking a specific spot with a strong current. The simplest rule, anywhere in Brazil: swim near a lifeguard post (posto), and ask the lifeguard where the safest water is that day. They know their stretch of sand better than anyone.

Understanding rip currents

Rip currents are strong channels of water flowing away from the shore. They can carry even confident swimmers out of their depth quickly, and they are more common in bigger surf and near river mouths, estuaries, piers and groynes. Often a rip looks deceptively calm — a darker, rippled channel where waves aren’t breaking, sometimes with foam or debris drifting seawards.

If you’re caught in a rip, the RNLI’s advice is clear:

• Don’t try to swim against it — you’ll exhaust yourself.
• If you can stand, wade — don’t swim.
• If you can, swim parallel to the shore until you’re free of the current, then head for the beach.
• Raise your hand and shout for help.
• If you’re struggling, conserve your energy and Float to Live.

Float to Live: the skill worth practising

Cold water and panic are a dangerous combination. The RNLI’s Float to Live technique buys you time to calm your breathing and think:

1. Tilt your head back, submerging your ears.
2. Relax and try to control your breathing.
3. Move your hands and legs gently to help you stay afloat.
4. Your legs may sink — that’s okay. We all float differently.

Practise it in a supervised pool before your next beach trip. It’s a small thing that makes a real difference to how confident you feel in open water.

Who to call

A few habits that make every swim better

• Choose a lifeguarded beach whenever you can, and check tide times before you go.
• Read the safety signs at the beach entrance — they tell you about local hazards.
• Skip alcohol before swimming, and keep children within arm’s reach in the water.
• Wear swimwear that stays put when you actually swim. A secure fit — supportive band, ties that hold, bottoms that don’t shift — means you’re thinking about the water, not your swimsuit.

Confidence in the water isn’t about being fearless. It’s about knowing the signs, respecting the sea, and enjoying every minute of it.