The Schedule of Cost Components item 13 (h) is for 'protective clothing'. Although this is not defined it is generally considered to include a personal item of safety equipment worn by the individual which is a necessary part of their role, in compliance with The Personal Protective Equipment at Work Regulations 1992.
The test, therefore, is whether the item is required as a result of an assessed risk of a person's health and safety at work. It is also common for a company name or logo to be added to the item of PPE, which is generally considered to be an 'allowable' cost.
In your case, PPE (provided it is in compliance with the requirement of section 8 of The Personal Protective Equipment Regulations 2002) would certainly be 'allowed'. Fleeces for staff may well be classed as 'allowed' where working in temporary site accommodation conditions, unless other means are equally or more effective to control a risk (heating). Personalised shirts, however, would probably not be an 'allowed' cost as they would not be classed as 'protective clothing' required to be provided by an Employer, who is not obliged to 'dress' their employees.
Apply the test as to whether the item would be classed as 'protective clothing' for a particular role and also whether the item in question complies with section 8 of the 2002 Regulations.