Safety work in confined spaces and a focus on

their classifications under the National

Occupational Standard (NOS)

Mac Stephens

“For all of our languages we

can’t communicate”

Christie Moore - Songwriter

A ‘Confined Space’ is….

“Any place, including any Chamber, Tank,

Vat, Silo, Pit, Trench, Pipe, Sewer, Flue,

Well or other similar space in which, by

virtue of its enclosed nature, there arises a

reasonably foreseeable Specified Risk”

CONFINED SPACE ?

CONFINED SPACE ?

N.C. 1, 2, 3, 4.

Cat 1, 2, 3, 4.

Low, Medium, High

Class A, B, C, O

Class 1, 2, 3

Class 3, 2, 1

Category R

Confined Space, Restricted access, Enclosed Space, Gas-check area

United Kingdom Standards Agency

Confined spaces are generally classified as being

either low, medium or high risk areas

These can on occasions, be de-classified to enclosed

areas where a suitable risk assessment has been

carried out

The two main guides are set out in the Water UK

guidelines and the Energy and Utility Skills

guidelines.

Low risk shallow entry with adequate natural or

mechanical ventilation

access is simple and unobstructed and there is no likely

risk of flooding e.g. meter pits, stairwells, valve

chambers or booster-pumping stations

There is a MEDIUM risk that a specified hazard

may be present

Will require the use of Escape Breathing

Apparatus

Will have one or more persons positioned outside

the confined space with responsibility for

controlling entry and dealing with emergencies

Vertical entry normally using a ladder or man-riding winch, requiring fall protection and a means of assisted rescue e.g. Rescue winch

Horizontal entry such as walking or climbing or working away from the bottom of a vertical entry with limited use of a rescue line

Entry may involve more than one person

Non-standard entries making rescue difficult

It is likely that a hazard will be present at

sometime during the entry

May involve complex entry procedures with

specific control and rescue arrangements

Will entail the use of self-contained breathing

apparatus or airline, detection equipment and

resuscitation equipment

Will require the presence of personnel with

responsibility for dealing with emergencies