Walk through a shelter

Concealed surface entry

The way in looks like part of the house or a garden building. A steel door at the top keeps out weather, debris and curious eyes. A camera and intercom let you see who is outside before you open it.

How we keep shelters discreet

Entry stair

The stair drops about 3 metres. Every metre of earth and concrete between you and the surface cuts radiation, which is why the living space sits well below ground.

In this model 16 steps, handrails on both sides, non-slip nosings.

Shielded entry passage

At the foot of the stair the route turns at a right angle. Radiation travels in straight lines, so a turn means there is no direct path from the surface to the door. Keep this passage clear of storage.

Doors and exits, part by part

Blast door

A steel door in a steel frame cast into the concrete, rated to the shelter's design overpressure. Gas-tight seals, locking bolts and lever handles on both sides. It opens outwards, so a pressure wave pushes it harder into its frame.

Standard Rated and tested to the shelter's blast class (1 to 3 bar+). Lead time 8 to 16 weeks.

Decontamination shower

Anyone who arrives after fallout has started showers here before going further in. Taking off outer clothing removes most contamination; washing removes most of the rest. The water drains to a separate sealed tank.

How fallout decays: the 7-10 rule

Radiation survey meter and dosimeters

The survey meter checks each person, and the air outside, for contamination. Personal dosimeters record what each person has received. Together they decide when it is safe to go out, and for how long.

Checks Calibration as the maker specifies, typically every year.

Protective clothing

Coveralls, gloves, boots and respirators for anyone who has to step outside, for example to check the intake or clear the hatch. They come off in the airlock and never go further in.

Contaminated clothing bin

Outer clothing goes into a lidded, sealed bin and stays in the airlock. Bag it, label it and keep it away from people.

Gas-tight inner door

With the blast door it forms the airlock: only one door is open at a time, so people can come in and clean up without breaking the seal. The gauge beside it shows the shelter's overpressure.

Standard Air-tightness tested at commissioning. Checks Seal inspection every year.

Monitoring panel

You cannot see radiation or smell carbon monoxide, so instruments do the noticing. One panel shows carbon dioxide, oxygen, carbon monoxide, overpressure, temperature, humidity and the dose rate inside, and sounds an alarm before air becomes unsafe.

Monitoring, part by part

Fire extinguishers

A sealed room is no place for a fire. Cooking is electric, there are no flames anywhere inside, and extinguishers that are safe on electrical fires sit by every exit.

Blast valve on the air intake

Outside air comes down this pipe. The blast valve closes in milliseconds when a pressure wave arrives, then reopens. Every intake and exhaust has one.

Standard Shock-tested to the shelter's blast class. Checks Movement test every year.

HEPA particle filter

Captures fallout dust, smoke, PM2.5 and biological particles. H14 captures at least 99.995% of the most penetrating particle size. The gauge on top shows how clogged it is.

Standard EN 1822 / ISO 29463 filter classes. In this model HEPA H14, standard on Keep and Citadel.

Gas filters

Activated carbon adsorbs chemical agents and many toxic gases. The filters stay sealed until they are needed, and are replaced after any exposure.

In this model Two military-grade CBRN filters.

NBC ventilation unit

Draws outside air through the filters and pushes it into the shelter. It runs on electricity, and the hand crank keeps air moving if every power source fails.

Lead time 8 to 16 weeks, often imported. Checks Run monthly, serviced every year.

Clean air, three levels

CO₂ scrubber

When fires burn outside, even filtered air carries smoke and carbon monoxide. Recirculation mode closes the intake and scrubs the carbon dioxide everyone breathes out from the air already inside.

Overpressure valves

They hold the shelter slightly above outside pressure, so any leak flows outwards. Filtered air leaks out; outside air never leaks in.

Checks Gauge reading in every drill.

Cooling, duty and standby

The ground stays near the local average temperature, but each person gives off about 100 watts. Without cooling, a full shelter overheats in hours. Keep-class shelters have a second unit on standby.

Designing for Indian heat and monsoon

Battery bank

Lithium iron phosphate batteries carry the shelter through outages, charged by concealed solar and the generator.

Inverter and load priorities

When power runs low, comfort loads switch off first and air goes last. Air never stops.

In this model 1 air, 2 water, 3 lights, 4 comfort.

Generator

Sits in a vented enclosure with its exhaust far from the air intake, and runs on stabilised fuel. Carbon monoxide alarms are standard in every shelter.

Sump and twin pumps

Collects any water that reaches the structure and pumps it out on shelter power, with a standby pump. India's monsoon makes this one of the most important parts of the build.

Checks Test run every quarter.

Living and dining room

Thirty days is a long time underground. A table for everyone, a sofa, books and games, warm light and a fixed daily routine keep people steady.

Communications desk

Shielded radios for official broadcasts and licensed two-way radio. Satellite equipment only where Indian law permits it.

First aid and medicines

A stocked medical cabinet, with each person's regular medicines for the full sealed period and a written list of who takes what.

Make a family emergency plan

Bunks

Six beds in three double bunks, each with a reading light, a curtain for privacy and storage underneath. Lockers hold clothes and personal things.

Escape tunnel

A second way out, in case the main entry is blocked. It leads away from the house so it comes up outside any collapse zone. Many are crawl-height; this one is walk-through.

Escape hatch

Built to the same blast class as the main entry, opens from inside and outside, and is hidden at the surface. It is opened in every drill.

Lead time 8 to 12 weeks.

Electric kitchen

Induction hob, microwave, kettle and a pressure cooker. No flames inside: gas burns oxygen and makes carbon monoxide.

Food store

About 2,200 kcal per adult per day, adjusted for children, elders and medical needs, with a 10% buffer. Ready meals, staples, oral rehydration salts and vitamins, labelled by date and replaced before they expire. Non-vegetarian food is stored separately.

Food, planned with you

Staples

Nitrogen-packed rice, atta and dal keep for years. With ghee, milk powder, jaggery and dry fruits they make the base of every diet.

Separate diet stores

Each diet has its own sealed store and utensils: Jain, vegan and satvik, halal, and medical diets such as diabetic or gluten-free. We plan for fasts such as Navratri, Ramadan and Paryushan.

Water tanks

At least 4 litres per person per day for drinking and cooking, plus a reserve, in food-grade tanks that our team rotates. Six people for 30 days need 720 litres just to drink and cook.

In this model Three 1,000-litre tanks, with sight tubes to read the level.

RO and UV purification

Sediment and carbon filters, a reverse osmosis membrane and an ultraviolet lamp make stored or borewell water safe to drink.

Gravity filter

Needs no power at all. If everything else fails, water poured in the top comes out clean at the tap.

Toilet

A chemical or flushing toilet that empties into a sealed holding tank, plus a basin and a shower. An extract fan keeps the air moving.

Holding tank and backflow valve

Waste goes to a sealed tank under the floor. The backflow valve keeps the sewer line closed, so nothing, and no air, comes back in from outside.

Daily routine

Air checks, meals, radio, chores, school and exercise at fixed times. A routine makes 30 days manageable, and we drill it with your family before it is ever needed.

The emergency plan