Science departments should stop putting up imaginary barriers and get stuck in. John Tranter dispels some widely held myths about experiments
You can't do that - it's been banned for years! How often is this woeful cry heard in school science departments, especially when a new teacher arrives from another education authority and surveys the current scheme of work? In some schools, science teachers rarely try any new practical activities because they assume that fears of contravening health and safety regulations must apply, or are worried that they will have to fight off litigation if something were to go awry. But such teachers are quite, quite wrong.
You can dissect eyes, you can culture microbes from unwashed hands, you can use mercury and carry out the thermite reaction (preferably under water), you can charge pupils to high voltages with Van de Graaff generators.
Virtually no practical activities or chemicals of significance in science teaching are banned nationally. Even if an accident did happen, it would probably be the employer who would be pursued through the courts.
With a few, straightforward safety precautions, a science teacher's options are wide open. It is true that health and safety regulations do impose certain duties on teachers who are required to assess the risks of any hazardous substances or practicals that they plan to use or carry out. Yet risk assessment can, nevertheless, be really liberating. Having thought through what is involved, considered problems that might be caused by pupils' lack of skills or misbehaviour, and applied the necessary control measures to keep things healthy or safe, a teacher can happily proceed.
So what other widely-believed science myths should now be dispelled? No, cheek-cell sampling is not usually banned. Nor are investigations using saliva or urine. Human blood samples may be taken, if permitted by the employer (and quite a few now have given their permission). There are no restrictions on investigations with radioactive sources, other than the need to adopt sensible policies and precautions (it is arguably irresponsible not to use radioactive isotopes in educating future citizens and so help them to gain a rational understanding of the values and dangers of radioactive substances). The burning of peanuts is allowed, though it is highly prudent to use alternatives such as Cheesy Wotsits or Monster Munch if the school has a pupil with a nut allergy. Ninhydrin is not carcinogenic and can be used safely in amino acid chromatography. Formaldehyde solution is perfectly OK to use - with care - to kill microbes. It is possible to heat nitrates in the open laboratory without generating dangerous levels of fumes, though the room must be well ventilated and the amounts of nitrates that are heated must also be limited to less than 1g. Giant African land snails are permitted in the UK and do not cause meningitis (despite much recent misreporting in the US and elsewhere). And yes, the bacterium, E.
coli, can be cultured (using a "safe" strain, such as K12).
So are there any things that science teachers are not allowed to do? Well, benzene is banned and, therefore, it is not permitted to carry out fractional distillation using genuine crude oil (which contains small amounts of benzene) -a substitute must be used. You do need to be a bit careful with locusts - do not breed them all year round as this will increase the chances of becoming sensitised to dust from their cages. Model steam engines should not be used with liquid fuels, such as industrial methylated spirits. Old-fashioned radiant heaters, where it is possible to make direct contact with live components, must no longer be used.
These examples, however, are drawn from a very short list of "do nots" or "can nots", and the restrictions do not significantly limit most science teachers' freedom to excite and innovate. Only a few education employers may have imposed local "bans" on health and safety grounds. Now, the next time a colleague tells you "That's not allowed", in most cases you can reply "Oh, yes it is"!
* Teachers in all education authorities in the UK, other than Scotland, and most colleges and independent schools, are already members and can check out the truth of any myths and rumours currently circulating by contacting the CLEAPSS School Science Service Tel: 01895 251496 www.cleapss.org.uk
John Tranter is senior adviser, CLEAPSS School Science Service