Almost two-thirds of NHS staff were unaware of the new legislation on safe staffing levels which came into effect last month, according to a survey from the union Unison.
The survey also found that 89% had not received training on the regulations, which began on April 1.
Meanwhile, about eight in ten staff said they did not have confidence in the existing procedures for dealing with staffing levels.
The survey was carried out in March, before the new law came into force, with 3,781 people responding.
The Health and Care (Staffing) Act was passed in the Scottish Parliament in 2019, but its implementation was delayed – in part due to the coronavirus pandemic.
It is the first legislation in the UK to set out requirements for safe staffing levels across both the health and care sectors.
Health secretary Neil Gray hailed April 1 as a “significant day” as the law came into effect.
Unison said many incidents of short-staffing in the NHS are not being reported as the existing recording tool, Datix, is time-consuming and cumbersome.
Matt McLaughlin, Unison Scotland’s head of health, said: “The government has had over four years to prepare for this new law, yet guidance was only made available four days before it became law.
“There’s a direct link between staffing levels and high quality outcomes for patients.
“Our members repeatedly tell us they do not have enough staff or enough time to give patients the care they need and deserve.
“In wards where they do meet staffing requirements, there is often not the correct skill mix to meet patients’ needs. This puts patients’ safety at risk and puts staff in unacceptably stressful situations.
“The reality is that staff don’t believe things are safe and NHS staff are left picking up the slack while no one holds their hospitals accountable.”
He added: “The Scottish Government does not have a true picture of the scale of the short-staffing situation in the NHS as incidents of short-staffing are chronically under-reported – staff simply do not have the time. And an obvious weakness is that key support staff are not included.
“The Act is potentially a powerful tool for driving up standards – but it can only make a difference if people know how to use it.
“And when incidents are reported, there is help from health boards to fix the situation.”
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