is storm glass liquid dangerous

Is storm glass liquid dangerous? You are likely to have this question if you do not just rely on the weather forecast on TV and want to check it yourself.

A storm glass or a weather glass is quite fascinating and helps you get an idea about changing temperature, atmospheric pressure, and humidity.

But, sometimes, you may accidentally break it, and that is when you are exposed to that liquid.

That is when you wonder, “Is storm glass liquid toxic?”

No, storm glass liquid is not toxic under normal conditions because it only contains chemicals like ammonium chloride, potassium nitrate, and alcohol solution.

What is a Storm Glass and Does it Work? 

traditional weather barometer

A storm glass is a chemical barometer. Admiral Robert Fitzroy used one on Darwin’s Beagle voyage and they have been used ever since.

They became very popular in the 1930s as an affordable device for predicting the weather at home.

But, they were invented in the 1700s around the same time the traditional weather barometer was invented.

Predicting the weather by scientific means created a bit of a stir but a barometer was incredibly expensive to buy and a storm glass wasn’t.

Fact: Be sure to place storm glass in an area where the temperature does not change abruptly or you will not get accurate results. 

The Incredible Storm Glass

incredible storm glass

There has always been speculation on how well storm glasses work. The truth is that a storm glass works much better than a bunch of seaweed.  

Storm glasses contain such a delicate balance of chemicals it would only take one proportion to be out for the whole thing not to work.

Weather predictions are made based on how crystalized the solution is.

The consensus seems to be that storm glasses are accurate at about the same rate seaweed is, about 50% of the time. 

Is Storm Glass Liquid Dangerous or Not?

The original purpose of storm glasses was foretelling weather shifts.

The appearance of the liquid in the glass may alter as the weather does, signaling the approach of a storm or a shift in temperature.

But, because of their unique style and rich history, many people use storm glasses for decorative purposes.

is storm glass dangerous or not

No matter why you have one in your home, it is natural to worry if you break it.

But, thankfully, under normal conditions the liquid in a storm glass is not dangerous.

Still, you need to remember that it does contain chemicals, and have the potential to be unpleasant or even harmful if misused.

Fact: The alcohol in storm glasses is flammable, so they are best placed away from open windows and direct sunlight and other heat sources. 

What are the Chemicals Used in Storm Glass?

To determine the toxicity of storm glasses, you need to know the chemicals they contain.

In most cases, you will find a combination of certain chemicals, such as:

  • Alcohol or an ethanol/water solution
  • Potassium nitrate
  • Ammonium chloride
  • Camphor
chemical camphor oil

In the old days, camphor oil, was extracted from camphor laurels.

Modern storm glasses are more likely to contain synthetic camphor oil made from turpentine which is from the same group of plant oils.

Camphor is one of three solids dissolved into the alcohol to form a clear solution. 

The other two are salts. Ammonium chloride, (NH4Cl), which is slightly acidic, and potassium nitrate, (KNO3) which is used in fireworks, fertilizer and rocket propulsion. 

What is the Liquid in a Storm Glass?

It’s a liquid that looks and acts like water, although it is a solution of equal parts water and ethanol, a natural grain alcohol.

In commercially mass-produced storm glasses, this mix is preferred since it reliably produces crystals and is relatively inexpensive.

The formation of salt crystals was thought to be triggered by changes in air pressure and temperature together.

salt crystal

Although unlikely, there may still be some truth to this.

However, crystals are unable to form in any solution that is in some way dirty or contaminated.

If nothing else, the alcohol keeps the unit sterile which may help its crystal-forming reliability.

Fact: Bespoke storm glasses tend to stick with tradition and use more alcohol even real vodka.  

Are the Chemicals in a Storm Glass Toxic?

No. The chemicals in a storm glass are not classed as toxic. The solution inside isn’t poisonous, although the components are irritants.

This is especially true for camphor, which could cause problems if ingested, splashed in the eyes, or left on the skin.

volume of camphor oil

Camphor oil, is a plant extract that has been long exploited for its properties and is still used in things like:

  • Muscle warming balms
  • Make up
  • Pesticides
  • Varnishes

When used correctly, camphor is perfectly safe. 

The Idea of using Storm Glass

Fitzroy came up with a reference chart that linked weather conditions to the state of the solution, or rather, the extent to which the salts had condensed out of the solution to form crystals.

How accurate the chart is hasn’t been investigated under scientific conditions although many lay people have tested it, claiming it makes accurate predictions about half the time.

It is easy to see why using storm glass weather predictors would be popular.

Linking weather conditions to a liquid’s clarity sort of makes sense, and it is easy to use as well.

For instance:

  • A clear liquid means clear weather.
  • A cloudy liquid means cloudy weather is coming, maybe rain.
  • Small dots in the liquid predict foggy weather.
  • Cloudy with small particles forecast thunderstorms or snow, if it is cold enough.
  • Large flakes in the liquid indicate incoming overcast skies with rain or snow.
  • Crystals at the bottom predict frost underfoot.
  • Threads near the top mean there is wind on the way.

The Accuracy of Storm Glass

accuracy of storm glass

The only problem with the chart is that it works on the premise that changes in atmospheric pressure can always affect chemical changes in a liquid.

And the liquid in this case is held in a sealed container. But, the premise is not always true.

This leaves storm glasses entirely dependent on detecting changes in temperature, which could sometimes be down to the weather.

But, they are more likely due to heat changes in the storm glass’ immediate location.

This is what renders them somewhat unreliable as weather-predicting devices.    

What To Do if You Break a Storm Glass?

One reason storm glasses have seen a recent resurgence in popularity is that they can be very aesthetically pleasing.

Setups come in all sorts of shapes and sizes.

storm glass broken

It is the solution being in a sealed container that is important, what the container looks like is not, which has allowed for a certain amount of creativity.

These days storm glasses are admired more as works of art or quirky ornaments and great conversation pieces at dinner parties.

It is quite like as they were at the height of their fame in the 1930s. But accidents happen. 

Things to Do When You Break Your Storm Glass

The first thing to do if a unit gets broken is open a window for ventilation.

The fumes will dissipate much faster and make it safer to deal with the practicalities of broken glass and spilt solution.

If left, the ethanol will evaporate off first, leaving the water, which will take longer.

The camphor and salts will eventually be left as particle solids that can be dusted or vacuumed away.

However, leaving a spill with irritants, such as camphor, isn’t always a sensible solution, especially if there are animals and children around.

In this case, cleaning it up with a warm soapy solution will neutralize the camphor and lift and trap the salts in its viscous solution.

It is best to wear gloves. 

How to Dispose of a Storm Glass

how to dispose storm glass

Broken storm glass should be disposed of in the same way as any broken glass.

However, this time, wearing gloves is an absolute must. Camphor or alcohol in a fresh cut will sting and be extremely painful.

With that in mind, the glass pieces should be carefully wrapped and taken for recycling in a suitably labeled container.

Fact: Do not place storm glass near a heating or cooling unit, and test its performance in different locations to find the best place for accurate results. 


Is storm glass liquid dangerous? In most cases, it is not. A storm glass is a sealed airtight unit and safe to use in normal circumstances.

However, if a glass does get broken, breathing in the fumes wouldn’t be a good idea.

The reason is that it still contains chemicals, which are usually safe in most cases, but you should still avoid mishandling.