Strictly speaking "First Aid" can only be provided in a workplace by those persons who have completed an HSE approved course and have a valid, current, certificate.
The reqirements for first aid in your school or college are set out in The Health and Safety (First-Aid) Regulations 1981. This says that you must:
Assess your first aid needs - determine how many first aiders you need and if they need any special taining. There is guidance in the document about how to judge the numbers and there is unlikely to be any need for specialised training.
Appoint someone to take charge of the first aid - this includes looking after the equipment, facilities and calling the emergency services. No formal training is needed for this. There can be more than one person and this would be a good idea as an appointed person must be on site whenever people are at work.
Provide an adequate number of suitable first-aid kits - what these contain is not mandated in law but guidance can be found in Appendix 2 of the regulations.
Provide at least one trained first aider - There is no legal requirement for all workplaces always to have trained first-aiders but given the size of schools and colleges, the number of people present and some of the activities that take place it should be seen as essential: especially in secondary schols or colleges. The number of first aiders is flexible. You just need to make sure that there is always someone on site who can reach an incident in good time.
In many such incidents in the laboratory, time is of the essence. Action should be taken by staff on the spot, even if they are not recognised First Aiders. These actions are know as Immediate Remedial Measures.
This is not pressuring anyone into attempting medical treatment they know little about. For insctance, normally, only a qualified First Aider should carry out cardiac pulmonary resuscitation (CPR) and other specialised techniques.
Taking action can simply mean call for a first aider and stay with the casualty. But there are some simple measures that can be carried out that will minimise the harm caused before the first-aider arrives. Details of these can be found from the pages below.