>>
Site Map
>>
Forums
>>
NVQ Level 4 OHSP
Forum module - topics in forum:
NVQ Level 4 OHSP -
Confined Spaces
I'm currently working my way through an nvq paper on confined spaces and I've come to a standstill. hopefully someone will be able to point me in the right direction.
I've been asked to "calculate the air requirements for a person in a confined space and include references to source"
any assistance would be a great help
Air requirements for Confined Spaces
Dear Craig,
The amount of oxygen in air is 21%; the lowest acceptable acceptable amount of oxygen in air is 16%. A person breathes 15-40 l/min dependant upon the work load. The amount of oxygen in breathed air is reduced by ~3% to around 18%. It should be noted that an oxygen content of 18% is generally used as a safety limit rather than 16%.
Assuming a 1 cu m, (1000 l) volume, then the available oxygen is 3% (21%-18%)of the total volume (30 litres). Assuming the person is working hard with a breathing rate of 40 l/min, the available oxygen will be used up in 45 secs.
Note that this does not take into account the presence ot toxic gases, mixing of the air, or the build up of carbon dioxide which increases breathing and confusion.
Hope that this helps for your assignment.
References:
Safety and Health in Confined Spaces Neil McManus ISBN 1-56670-326-3
Regards and good luck
Barry
