Scalpels can be reused
One in four hospital trusts in England is failing to meet national standards on the cleanliness of surgical equipment, a watchdog has reported.
The Healthcare Commission found that the number of trusts with satisfactory decontamination standards fell by 7% last year.
Specialists said the failure put patients at higher risk of infection.
The Department of Health said it was working with trusts and decontamination companies to improve matters.
Many types of surgical equipment, such as scalpels, can be reused over and over again, but must be completely cleaned then sterilised before the next patient.
The Healthcare Commission standard states that trusts should ensure that proper decontamination is happening, and that risks are "well managed".
This means they need the right procedures and facilities in place to minimise the risk of unsterilised equipment reaching the patient.
Under the Healthcheck scheme, trusts declare whether they are meeting the standard, producing paperwork to support this, and one in five are then inspected by the commission to make sure.
Last year, 77.3% of trusts said they were meeting the standards, compared with 84.8% the previous year.
The Association for Perioperative Practice, which works to improve the standard of care offered during and after operations, said these were the worst results since the Healthcare Commission's new "NHS Healthcheck" was launched.
It said that moves which meant fewer hospitals carried out their own decontamination, sending the work to "supercentres" catering for many different hospitals, could be contributing to the low quality.
Diane Gilmour, from the association, said the results were "extremely concerning".
"Of all the core standards examined by the Healthcare Commission, this is by some way the poorest performance.
"Failure to reach these standards puts patients at risk, and if this downward spiral continues the repercussions for patients care could be severe."
A spokesman for the Healthcare Commission it was "concerned" by the performance of some trusts.
"This decline could be because trusts are now much more aware of what they need to do to meet best practice.
"This involves decontamination away from treatment and clinical areas and preferably in an accredited specialised facility or at least in a dedicated room meeting essential requirements.
"From April next year, every NHS trust will need to comply with requirements on infection control in order to be registered with the new Care Quality Commission.
"The results of the annual health check show that some trusts need to strengthen their systems before they can be confident they will meet requirements of registration."
A spokesman for the Department of Health said it was addressing the issue.
"We have invested over £200 million in improving decontamination services in the NHS in England since 2001 and we will continue to support Trusts to provide the highest standards of decontamination of instruments as part of their drive against healthcare associated infection.
"We are helping PCTs to draw up a local action plans where necessary and we are working closely with both them and the private sector provider to resolve any issues."