31 year old victim taken to hospital after attack on Thursday night.
'Spit Guards' Given To Herts Police
Hertfordshire Police have introduced specially-made hoods to protect officers and members of the public from criminals who spit.
Officers across the county will now be equipped with the covers, made from light, see-through fabric, which can be put over the heads of suspects who are acting aggressively.
Personal Safety trainer Adam Hawes said: "Being spat at is one of the most disgusting things that can be experienced by the public, officers and staff and in some cases can be dangerous.
"These spit guards will only be put on a person who has been spitting at the public or officers or is threatening to spit."
The spit guards are seen as a safer alternative than using a piece of the offender's clothing or a custody blanket to cover their face.
Hertfordshire police said they were being rolled out across a number of forces.
Both robberies happened within 20 minutes of each other on Wednesday night.
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