SPIT and bite guards are being introduced to protect West Midlands police and the public.
The force says 231 officers last year were placed at risk of serious disease by being spat at.
They will only be fitted to detainees who has already spat or who threatens to spit, the force insists.
It adds victims have included PC Michael Bruce, based in Coventry, spat at by a violent man as he and his colleague PC Alan O’Shea were attempting to arrest.
The force said: “The pair were showered in spittle and blood, and faced an agonising six-month wait for continuous medical tests to final prove they were not infected with HIV, hepatitis and tuberculosis.
“The situation meant that Alan was unable to visit a relative who was undergoing chemotherapy, while Michael’s nine-year-old daughter and one-year-old son also had to be screened for hepatitis after he initially tested positive for the disease.
“Medics subsequently established that the test was wrong and he was given the all clear.”
Their attacker was handed a suspended sentence and fined by the court.
PC Bruce said: “I was a police officer who was just doing my job, and yet I ended up with a six month sentence as I waited for the results of the tests.”
West Midlands Police says the new guards – already used by 22 other forces nationwide – should also reduce the level of force employed by officers when detaining someone spitting.
It says it takes several officers to properly physically restrain the person, while they often have to improvise to protect themselves from spittle, blood and phlegm – such as by drawing down a detainee’s hood or riding up their jumper or t-shirt.
The spit guards are made from a loose-fitting, net-like material, with a reinforced section around the jawline.
The devices guarantee no mouth or airway blockage, says the force.
It adds that, when fitted, the wearer with be constantly monitored and the guard removed at the earliest opportunity.
Chief Constable Dave Thompson said: “The decision to introduce spit and bite guards into West Midlands Police is not one I’ve taken lightly.
“Some considerable work has gone into this and on the basis of everything I have seen, I believe this is absolutely the right decision.
“I acknowledge that some people will feel worried about their introduction.
“I want to reassure them that safeguards are in place and if they are used, this will be recorded. That data will be made available and will be scrutinised by local people.
“The Police and Crime Commissioner (PCC) will also hold me to account for the actions of my officers.”
PCC David Jamieson, said: “At a recent public consultation there was overwhelming support for this move. The force will use spit guards only when absolutely necessary.”
Officers have also been issued with surgical masks with an inbuilt eye shield similar to those worn by dentists.
The cost of the guards will be £11,000 and will take around three months to introduce.
