The relevant regulations are the Health and Safety (First Aid) Regulations 1981. This guidance to the regulations sets out the difference between a 'first aider' and an 'appointed person':
In any company, the number and type of first aid personnel would be based on an assessment. In assessing need, employers need to consider:
- workplace hazards and risks;
- the size of the organisation;
- the organisation's history of accidents;
- the nature and distribution of the workforce;
- the remoteness of the site from emergency medical services;
- the needs of travelling, remote and lone workers;
- employees working on shared or multi-occupied sites;
- annual leave and other absences of first aiders and appointed person
Whilst the regulations do not give specific personnel numbers, the guidance does give suggested numbers of first aid personnel: