Officers with the Metropolitan Police are to be quizzed on whether they want to carry a spit guard.
A survey by the Metropolitan Police Federation will ask members whether they have ever been spat at or bitten while on duty over the last two years – and whether they would want to have a guard at their disposal for protection.
Scotland Yard boss Cressida Dick has previously said using spit guards on the streets could make police officers more likely to get “a good kicking”.
The mesh hoods are used in Metropolitan Police custody suites around three times per week, but are not issued to Met officers on the beat, unlike those with British Transport Police on patrol in London.
Ken Marsh, chairman of the Metropolitan Police Federation, said officers “deserve as much protection as we can give them”.
He added: “It’s absolutely horrific to be spat at.
"My colleagues… don’t in any way deserve to go to work and be assaulted in this manner.
“Anecdotally we know officers are being spat at far too often – but we need to be able to take the evidence to the Commissioner’s office."
The Federation said details of the dangers and frequency of spitting attacks would help convince Ms Dick to issue them to all police officers in London.
Currently the Met uses spit guards in custody suites where several officers and supervisors are present.
Earlier in September, Ms Dick said using the guards in such an environment was very different to using them out on the streets.
She added: “Those of you who have real concerns about the guard would say that when you put it on somebody’s head it is potentially highly frightening and makes somebody feel very claustrophobic.
“It does create, in those who are looking at it being applied, a sense that this is an oppressive thing to do.”
The guards, used by 37 forces in England and Wales, have been criticised by human rights groups including Amnesty International, which called them “a cruel and dangerous form of restraint”.