Is it safe? August 20 2014, 0 Comments


Quite a few customers at the markets on the weekend, quizzed me over soap making methods and safety issues...highly unusual. The odd person occasionally asks some questions- a few...tweaked my curiosity.

Then my memory likes to wander around and search for relevant fragments…triggered by words/associations. So now it’s replaying that infamous torture scene from the movie “Marathon Man”, where Dr Szell (Sir Lawrence Olivier) asks Babe Levy (Dustin Hoffman), “Is it safe?”…before wielding the dental probe into Levy’s decaying tooth. How could anyone attend a dental appointment thereafter, without apprehension? My memory grabs on to trivia and files it away.

Apparently, various soap making workshops have been run recently in Brisbane, & the take home message from that exercise in my opinion is that not enough information has been passed on to attendees over the importance of safety practices in handling caustic soda...with children attending these workshops also. I've refused to run soap making workshops because of safety business insurance would be promptly terminated!

As I’ve explained before, a caustic soda (sodium hydroxide/NaOH)/water solution or ‘lye’ is required to make soap. NaOH is a highly corrosive, caustic and reactive chemical, and it should always be handled with appropriate safety precautions in place.

Caustic soda is produced from an electrolysed sodium chloride brine solution. This process works in much the same way that chlorine is produced for salt water swimming pools- the salt water being passed over the charged plates of the chlorinator cell which breaks down the salt into its natural components…one of which is chlorine.

Caustic soda is a strong alkali and highly corrosive. When it is used commercially, stringent safety precautions are required:
-       chemical resistant clothing/apron, shoes, protective gloves and safety glasses/face shield must be worn
-       the area must be fitted with a fume exhaust hood, safety shower and eyewash fountain
-       NaOH must be stored in a dry place- away from metals, and locked away from child access.

Now there are some clues that should be observed with good reason.

NaOH is:
-       both colourless and odourless
-       slippery when wet
-       exothermic, generating extreme heat when exposed to moisture…heat sufficient to cause skin burns on contact
-       capable of melting some plastics from the generated heat when mixed with water
-       unstable when combined with anything other than lukewarm water…if the water is either too hot or cold, a volcanic reaction can occur
-       corrosive as a generated vapour/mist, and a respiratory irritant…severely damaging nose, throat and lung tissues
-       highly corrosive and capable of dissolving animal proteins…causing severe skin burns on contact
-       reactant with several metals…causing the highly explosive and flammable hydrogen gas to form- only stainless steel can be contacted safely
-       capable of producing deadly carbon monoxide gas, when in contact with any sugar.

That’s quite an extensive list of cautionary notes to be mindful of whilst handling NaOH in soap making. Accidents happen…without question. I have visions of spilling the lye on the floor- then falling over on the slippery surface and having my clothes drenched in the burning solution…and unable to get up! Only once have I had an accident- a tiny NaOH grain went unnoticed on a fingertip while I worked. It burnt a tiny deep hole through all layers of skin quickly.

Never become complacent over handling this chemical. I am acutely aware of safety issues always- even after making soap daily for several years. I wear protective items. I mix the water and caustic soda outside in fresh air. I use thermometers. I keep a bottle and bowl of vinegar on the bench- ready to neutralise any splashes/spills. I have the security of a swimming pool a step away from the workroom to jump into immediately. I take no obvious risks ever- one splash of the solution in my eye could cost me my sight.

I have taken issue over soap making kits being sold and promoted as an activity to be done by children. I find this prospect outrageous. Even with adult supervision, accidents happen in a split second. Children do not develop acceptable levels of thought processing and physical co-ordination skills until after the age of 10 years.

Beyond the potential recipe for disaster in a child handling NaOH, a child is curious and impatient. Once the soap is mixed and poured, it is left to firm up for 24 hours. The process of saponification continues during this period. The soap mixture goes through various stages as the molecular changes occur. The mixture generates its own heat, and gradually goes in to a clear gel state- starting at the centre and gradually expanding outwards to the edges. During this period, the mixture is still highly corrosive- it could in fact be used as a paint stripper. Do you really want a child impatiently poking their finger in to the mixture to gauge how firm it is?

Anyone using caustic soda to make cold process soap for public sale is required to be registered with NICNAS- National Industrial Chemicals Notification Scheme, Australian Government Dept. of Health and Ageing. Anyone not registered is liable to hefty fines- $33K for an individual/$165K for a company. If a soap maker makes a mistake in their calculations or measurements of caustic soda, severe burns could result.

Soap makers are also required to carry product insurance to protect the buyer’s health interests. Unfortunately, soap is now viewed as a high risk insurance item- largely because of claims brought about through many body-washes, which have a high margin for error in mixing. Product insurance for soap has escalated- with few insurers prepared to cover soap/related products- with insurance costing me 40% of every sale. That doesn’t leave much scope for profitability in the equation.

So my take home message to those thinking about making their own soap…please take note of the safety issues surrounding the use of caustic soda. Never treat it casually…ever!

Some safety tips in soap making to always observe:
-       wear protective chemical resistant gear
-       work in a well ventilated space
-       measure ingredients accurately
-       only use hardened glass and stainless steel utensils
-       have ready access to a water supply for emergency use
-       have ready access to vinegar…the acid will neutralise the alkali caustic soda
-       use thermometers in both the lye solution and oils before mixing at same lowered temperature
-       add caustic soda SLOWLY to lukewarm water- if added too quickly, corrosive vapour will form…which should not be breathed
-       never add water to caustic soda…a volcanic eruption will occur, causing dangerous splashes- only add NaOH to water
-       wash hands thoroughly after soap making
-       wash equipment used in isolation of anything else
-       reserve any equipment used solely for soap making
-       keep caustic soda and poured soap mixture out of the reach of children.

As I’ve explained before, caustic soda- although used to make soap- does not exist in the final soap product. It is a part of a manufacturing process, and it is rendered inert within 24 hours of combining the ingredients…resulting in a solid soap salt and glycerine as a by-product instead.

Back to “Marathon Man” and its relevance to safety in soap making. Levy answers, “No, it’s not safe- it’s very dangerous- be careful.” The memory dots are connected!