The Confined Spaces Regulations 1997 set three core duties for any confined space work, including cleaning: avoid entry where the job can be done from outside, follow a safe system of work where entry is unavoidable, and put adequate emergency arrangements in place before work starts — sourced directly from HSE guidance. Silos, tanks, pits, ducts and vessels commonly meet the legal definition of a confined space, which changes how cleaning has to be planned and carried out.
What counts as a confined space?
HSE's guidance covers spaces that are substantially, though not always entirely, enclosed, where there is a reasonably foreseeable risk of serious injury from hazards such as a lack of oxygen, toxic or flammable atmosphere, free-flowing material, or difficulty escaping. Silos, storage tanks, vessels, pits, ducts, sumps and some sewers and drains are typical examples relevant to industrial cleaning.
The first duty: avoid entry
The Regulations' first requirement is to avoid entry to a confined space altogether where the work can be done from outside — for example by cleaning through an external access point, or using long-reach or remote equipment. Entry is only justified once that has genuinely been ruled out.
The second duty: safe system of work
Where entry cannot be avoided, work must follow a safe system of work covering atmospheric testing before and during entry, ventilation, isolation of the space from product, power or other hazards, the right PPE and RPE, and continuous communication between the entrant and a trained standby person outside. The Approved Code of Practice, L101, sets out how to assess and plan for this in detail, including who is fit and competent to enter for the specific task.
The third duty: emergency arrangements
Adequate emergency arrangements have to be in place before work starts, not improvised if something goes wrong — including rescue equipment and a trained standby person able to raise the alarm and begin rescue without themselves entering the space unprotected. Attempted rescue without the right arrangements is a recurring cause of multiple fatalities in confined space incidents.
How this applies specifically to cleaning
Cleaning inside a silo, tank or vessel is exactly the kind of confined space work the Regulations cover — it is our job to run the risk assessment, method statement, atmospheric testing and standby arrangements as standard, not to treat the space as an ordinary cleaning task with a permit added on.