Safe Work in Confined Spaces, Third Edition - What has Changed?

How will this affect you?

  • More clarity
  • Real-life examples
  • Further guidance

The third edition of, Safe Work in Confined Spaces (L101) published by the HSE, which came into force 19th December 2014, has certainly made some changes for the better.

Our Consultants have examined the new document, and the paragraphs below detail the major updates and changes from the Second Edition to the Third Edition.

This edition brings the ACOP up to date with regulatory and other changes, and the guidance has been simplified to make the understanding and use of the document easier, particularly with clarifying the definition of a confined space.  The text and requirements of the regulations themselves have not been changed – a copy of the text of the regulations can be viewed online.

Definition and Meaning of Confined Space

Most of the changes and additions to the document can be found in the first section, titled “Meaning of ‘Confined Space’ “.

The definition of a confined space (Regulation 1) has remained the same, however the guidance accompanying the regulation has been extensively re-written and added to.  Examples which are easy to relate to and will significantly aid understanding have been added.  These include:

  •  areas that could be confined spaces,
  • areas that could be mistaken for confined spaces (e.g. those that are enclosed but where a specified risk is not present),
  • specific examples of specified risks (including several mentions of wood pellets),
  • new risks (including fire suppression systems and deliberately hypoxic environments). and
  • areas that can become confined spaces due to the storage of certain substances.

The addition of a flow chart to this section to help determine whether an entry should be classified as a confined space illustrates the text of the guidance, however it adds little more than a summary of the text preceding it.  Following through the process, the chart asks the reader three questions: is the area enclosed (or substantially enclosed), is there a specified risk inherently present in the space, and does the task introduce a specified risk?   This simple process highlights that in order for an entry to be classified as a confined space it needs to be both enclosed (or substantially enclosed) and there must be a specified risk (whether it be inherent or task based).

Where this section falls short is in offering guidance on the need to, and the practicalities of, applying the term, ‘reasonably foreseeable’, and also the important fact that whilst an area may not be a confined space, in accordance with the legal definition, it may be prudent to apply control measures typically associated with confined space entry. 

Plant and Equipment

Extensive changes and editions have been made to both the ACOP and the Guidance in paragraphs 181 to 193.  This section falls under the title “Plant and Equipment”, and gives guidance and instruction on the inspection, calibration and testing of equipment used in connection with confined space entries.  This includes, resuscitation equipment (resuscitators, AEDs and similar), lifting equipment and respiratory protective equipment.  Whilst this section gives a broad overview of the equipment likely to be used and touches on inspection and service requirements, there is little detail on the exact requirements.  A sample inspection / maintenance regime would have been useful here. 

Miscellaneous Changes

Elsewhere in the document some isolated changes and additions have been made that may affect those planning or working in confined spaces:

In relation to smoking – the following text has been added to the guidance in paragraph 133, "exclusion area for smoking to a suitable distance beyond the confined space, for example where there is a risk of explosion."

In relation to the provision of defibrillators (AED) - the following text has been added to the ACOP in paragraph 149 - "Rescue equipment will often include …   … first aid equipment including automatic external defibrillators (AEDs) and other resuscitation equipment."

In relation to accredited training or competency assessment – the following paragraph has been added, paragraph 164, "Regulated qualifications in emergency rescue and casualty recovery from confined spaces are available.  Regulated qualifications are delivered by training centres recognised by a regulated 'awarding organisation' (AO).  These AO's are regulated by the qualification regulators against standards for the design, delivery and award or qualifications.  As part of the required standards, AO's must have dedicated quality assurance processes to approve and monitor their recognised training centres". 

Final Thoughts

Throughout the new document, the use of bullet points and shorter paragraphs makes referencing individual sections easier and aids understanding.  The addition of examples and real life situations which the reader can relate to are also seen as a significant improvement.

The information supporting the definition of a confined space will certainly bring some clarity and will help the reader to identify their confined space entries with greater confidence.

However, we feel that the distinction between lower and higher risk entries and the requirement for control measures commensurate with risk is not given sufficient emphasis.  There is very little specific information within the document (understandably so) which may leave the reader frustrated and their specific questions unanswered.

Whilst the third edition of ‘Safe Work in Confined Spaces’ is a user friendly and useful document, we feel it should be read in conjunction with other documents which give may give the reader more clarity.  We suggest that the Water UK, 'Classification and Management of Confined Space Entries', and the City and Guilds 6150 Assessment Scheme – both of which give specific examples of best practice - are a good starting point.

Useful Information

The text of the regulations can be viewed at the website -

Safe Work in Confined Spaces (L101) can be purchased from HSE books or downloaded free of charge from their website -

The Water UK, Classification and Management of Confined Space Entries can be downloaded from their website - type ‘confined space’ into the search box.

For information on the City and Guilds 6150 Scheme email and we will send you our factsheet.

For further information on interpretation of the ACOP or advice on any other aspect of confined space safety feel free to email our consultants on