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Product category: Materials and components
News Release from: Enviro Tech Europe | Subject: Alternatives to Trike
Edited by the Engineeringtalk Editorial Team on 30 January 2006

Legislation and solvent cleaning in
Europe

Derek Carpenter examines the current state of European legislation affecting solvents for vapour degreasing in the light of the Solvent Emissions Directive.

For anyone dealing with solvents over the past 15 years it will have seemed a period of uncertainty and change For most people, manufacturing finished or semi-finished parts inevitably involved solvent cleaning using a vapour degreaser

For the UK at least this was the tried and tested method that could provide consistent results.

During the 1980s you could probably have split users product choice equally into the 1.1.1 trichloroethane or trichloroethylene (Trike) camps.

Then came concerns for the environment - in particular ozone depletion and its potential damage to our stratosphere.

As 1.1.1 trichloroethane had the greater ozone depletion potential and an atmospheric lifetime beyond 5 years it was phased out.

No absolute science existed at the time but a precautionary principle and the alternative availability of trichloroethylene seemed to provide a necessary response to an uncertain dilemma.

I'm often asked whether the move was for political or scientific reasons.

I believe the science was never validated, if it ever existed.

As the years have passed the precautionary principle has "ruled" and resulted in major debate about the solvent legislation that has followed.

No-one would wish to argue against responsible protection of environment, operators and the community around us.

It is of course reasonable to expect a full scientific argument to exist prior to regulation and this cannot always be assumed.

In the end of course we must ensure all legal obligations in law are met to protect our business and show our due diligence.

The trends driven by the European Parliament looks set to continue to provide challenges.

With a stated intention to test and approve 30,000 to 100,000 chemical products, Parliament's study prepares the UK for a loss of GBP 3.42 billion a year.

The fear remains that no budget exists to ensure a diligent scientific approach.

Inevitably our options to achieve chemical cleaning will decrease.

The precautionary principle may yet be held as the final word for legislation.

But I hope it never becomes a substitute for hard science.

Coming up to date, the majority of solvent users with a vapour degreasing system will be using trichloroethylene.

Others may have chosen methylene chloride or perchloroethylene as the other alternative chlorinated group, depending on where they are in Europe.

Beyond chlorinated solvents the fastest growing alternative comes from n-propyl bromide technology.

All are direct replacements for vapour degreasing.

At the outset we must understand one constant thread of solvent legislation - use less.

In time a typical solvent user will be 1 to 3 tonnes per annum.

That's the immediate challenge.

The days when companies used over 100 tonnes per annum are gone, and we can be grateful for that.

Trichloroethylene faces the most immediate issues.

Why? Because the legislation has been in place since 1999 and a response is now needed to meet the legal obligations outlined.

One piece of legislation in Europe is demanding everyone's attention: the Solvent Emissions Directive (1999/13/EC) has a serious impact on a user's continuing ability to use trichloroethylene.

Oddly, the Solvent Emissions Directive (SED) appears to have caused confusion - even though it originates from 1999.

One constant is that trichloroethylene must now be considered as carcinogenic, with an obligation to seek its elimination.

In general, the directive offers three choices of product classifications: R45 - may cause cancer; R40 - limited evidence of a carcinogenic effect; and R20 - harmful by inhalation.

Debates about the rights and wrongs of classifications can be contentious.

A risk phrase should be created where the potential risk might arise in "normal working circumstances".

At times it may appear that a hazard, albeit highly unlikely, has unfairly been issued a risk phrase.

In the end we are required to deal with the established rule of law.

Given the pressures on trichloroethylene, we should now be seeing some impact on its reduced use if the spirit of legislation is being upheld.

Looking at Western Europe, back in 1996 101,000 tonnes were in use.

By 2000 figures dropped to 74,000 tonnes and thereafter in 2001 to 62,000 tonnes (a decline of 53% in 6 years).

Latest figures available for 2003 are 38,000 tonnes with a realistic prediction for 2007 being below 10,000 (a 90% reduction over 11 years).

Even then, a permit for use will become necessary (as is currently the case in Scotland), in which special circumstances will need to apply.

The impact of legislation is clear.

The outcome brings product users back to assessing a suitable alternative.

This must always be measured by performance benefits but science is a guide to safety.

Most toxicological studies to consider safety profiles are performed on exposure to rats or mice.

These are important but no single study should ever make another void.

Risk assessment involves collecting as much data as possible to produce the best judgement.

The most popular alternative to chlorinated solvents has been n-propyl bromide.

One valuable comparative study by Dr Mark Stelljes acts as a very useful aid.

As a world renowned toxicologist with SLR International Corp (Concord, California) who specialises in risk assessment and management, he concluded a human in vitro bioassay study of commonly used cleaning solvents.

It is considered that this study marks the first time 1.1.1 trichloroethane, trichloroethylene, methylene chloride, perchloroethylene and EnSolv (stabilised n-propyl bromide) have been selected for an identical set of tests on human cells.

It assists on judgement of the relative human toxicity of these solvents.

Most toxic were trichloroethylene and perchloroethylene.

Least toxic were EnSolv (n-PB) and methylene chloride.

If you are a user of trichloroethylene, methylene chloride or perchloroethylene in excess of 1 tonne per annum (or any other VOC solvent as defined under SED in excess of 2 tonnes per annum), obligations exist under the directive.

1 tonne represents the following volumes: 685 litre trichloroethylene, 752 litre methylene chloride or 617 litre perchloroethylene.

Falling below these figures would provide the benefit of being exempt from this legislation.

Under Article 7 of the SED the most vital product considerations are: fitness for use; potential effects on human and occupational exposure; potential effects on environment; and economic consequences - in particular the costs and benefits of the options available.

If affected by SED obligations, users of Trike must aim at seeking an alternative in "the shortest possible time".

Other solvents with emissions targets must achieve the required standards, in some cases as low as 3ppm, no later than October 2007.

The natural outcome of needing to provide compliant systems has brought suitable products and engineering solutions closer together.

Machine manufacturers are co-operating with product manufacturers to produce a total solution by ensuring use of product will not exceed 1 tonne per annum.

It should never be forgotten that the greatest area of risk and losses on a vapour degreaser is the open top basket area.

Advice on SED, registration and obligations is usually available through a country's environment agency or equivalent.

Specialist advice and on hand technical support is valuable.

When seeking to understand the goals of legislation a good place to start is its principle.

It offers a sense of spirit behind it.

With the SED it is "to prevent or reduce the direct or indirect effects of volatile organic compounds (VOCs) into the environment, mainly into air and the potential risks to human health".

Never forget this extends to the community at large, as emissions go out to atmosphere.

So, consider now the need to establish any obligations, review your process, establish an action plan and carry it forward in the designated timescale which is now greatly reduced. Request a free brochure from Enviro Tech Europe ...

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