445365.pdf (49.66 MB)
The effects of protective clothing and its properties on energy consumption during different activities
thesis
posted on 2011-01-28, 14:18 authored by Lucy E. DormanThere are many situations where workers are required to wear personal
protective clothing (PPC), to protect against a primary hazard, such as heat
or chemicals. But the PPC can also create ergonomic problems and there
are important side effects which typically increase with rising protection
requirements. The most extensively studied side effect is that of increased
heat strain due to reduced heat and vapour transfer from the skin. Less
studied is the extra weight, bulk and stiffness of PPC garments which is
likely to increase the energy requirements of the worker, reduce the range of
movement and lead to impaired performance.
Current heat and cold stress standards assume workers are wearing light,
vapour permeable clothing. By failing to consider the metabolic effects of
actual PPC garments, the standards will underestimate heat production and
therefore current standards cannot be accurately applied to workers wearing
PPC. Information on the effect of the clothing on the wearer and the
interactions between PPC, wearer and environment is limited.
Data was collected to quantify the effect of PPC on metabolic load based on
the properties of the PPC for the EU THERMPROTECT project (GERD-CT-2002-00846). The main objective of the project was to provide data to allow
heat and cold stress assessment standards to be updated so that they need
no longer exclude specialised protective clothing.
The aim of this thesis was to investigate the effect of PPC and its properties
on energy consumption during work. For this purpose, the effects of a range
of PPC garments (Chapter 3), weight (Chapter 4), number of layers and
material friction (Chapter 5) and wet layers (Chapter 6) on energy
consumption whilst walking, stepping and completing an obstacle course
were studied. The impact of PPC on range of movement in the lower limbs
was also investigated (Chapter 7).
The main findings were; a) Increased metabolic cost of 2.4 - 20.9% when
walking, stepping and completing an obstacle course in PPC compared to a
control condition. b) An average metabolic rate increase of 2.7% per kg
increase in clothing weight, with greater increases with clothing that is
heavier on the limbs and in work requiring greater ranges of movement. c)
4.5 to 7.9% increase in metabolic cost of walking and completing an
obstacle course wearing 4 layers compared to a single layer control
condition of the same weight. d) Changes in range of movement in PPC due
to individual behavioural adaptations. e) Garment torso bulk is the strongest
correlate of an increased metabolic rate when working in PPC (r=0.828,
p<0.001). f) Garment leg bulk (r=0.615), lower sleeve weight (r=0.655) and
weight of the garment around the crotch (r=0.638) are also all positively
correlated with an increased metabolic rate. Total clothing weight and
clothing insulation had r values of 0.5 and 0.35 respectively.
This thesis has confirmed the major effect of clothing on metabolic rate, and
the importance of including this effect in standards and models.
Funding
Loughborough University
Assessment of thermal properties of protective clothing and their use
European Commission
Find out more...History
School
- Design and Creative Arts
Department
- Design
Publisher
Loughborough UniversityRights holder
© Lucy Ellen DormanPublication date
2007Notes
A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.EThOS Persistent ID
uk.bl.ethos.445365Language
- en
Supervisor(s)
George HavenithQualification name
- PhD
Qualification level
- Doctoral
This submission includes a signed certificate in addition to the thesis file(s)
- I have submitted a signed certificate