WHO have issued advice here:

https://www.who.int/emergencies/diseases/novel-coronavirus-2019/advice-for-public/when-and-how-to-use-masks

Safe removal of PPE doesn't just apply to masks. More than one study has shown that those wearing the single-use gloves that are found in healthcare, laboratories, etc., may on removing the gloves contaminate their hands with what is on the outside surface of the gloves. When providing practical glove removal training it is not unsual to find that even after having seen a demonstration of the correct removal technique over half will still contaminate their hands. In one study (Glove use among hairdressers: difficulties in the correct use of gloves among hairdressers and the effect of education, Oreskov KW, Søsted H, Johansen JD, Contact Dermatitis, 2015) 100% of those in the study contaminated their hands. Even after having been shown how to remove their gloves 58% still contaminated their hands. It is why hand decontamination after glove removal is so important.

This 3rd person, needs to be in full PPE themselves and have access to some sharp scissors and a large spring top bin in close proximity, together with a misting spraygun, preferably on a 5 litre spray tank than a small spray bottle, as workers tend to get tied quickly and sometimmes develop hand cramps when tired. 

You may have already noticed, that wearing full PPE makes you tired quicker, so expect people to be frazzled, having the 3rd person cut off the PPE is often easier than struggling when tired.

Hi,

Good information on the NHS site about donning/doffing PPE.

https://www.england.nhs.uk/coronavirus/secondary-care/prevention/personal-protective-equipment-ppe/