Metropolitan Police response cars will carry equipment that will help officers to better deal with calls to acid attacks, the force said.
It comes after a recent spike in corrosive substance attacks, with more than 400 being carried out in the six months up to April this year, according to figures from 39 forces in England and Wales.
Some Met police cars will now carry five-litre bottles of water, with a full roll-out expected in the coming weeks.
The force is also looking at providing each borough with a kit, which as well as water would include protective eyewear and gloves.
A Metropolitan Police spokesman said: "We have been guided by the NHS, and the key treatment for these injuries is to flush the injury with lots of water."
He added that officers would also be receiving first aid training specific to dealing with acid attacks.
The Government is also looking at a new strategy to crackdown on acid attacks following a recent spate of high-profile incidents, including five assaults that were linked in London earlier this month.
The Home Office said it will work with police and the Ministry of Justice to assess whether powers available to the courts, including sentencing, are sufficient.
Home Secretary Amber Rudd has indicated acid attack convictions could soon carry life sentences.