As we said at the start of the last school year, few parents would see wearing ties at school as a safety issue. Millions of children have been wearing ties as part of their uniform for years without any problems.
Simple precautions such as removing the tie during laboratory work or around machinery make sense. But if the concern is really about children fighting, while clip-on ties may help, the real issue is discipline.
So HSE doesn't ban school ties - it's up to schools to make their own decisions about uniforms.