UNIVERSITY OF SOUTH AFRICA
College of Science, Engineering and Technology
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
MNO2608: Occupational Hygiene
Assessment 3 | Semester 2, 2026
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
MNO2608
Module Code:
Occupational Hygiene
Module Name:
Workplace Hazard Investigation: Sanding
Essay Topic:
Section and Vehicle Spraying Workshop
Assessment 3
Assignment Number:
Semester 2, 2026
Semester:
September 2026
Due Date:
Submitted in partial fulfilment of the requirements for Occupational Hygiene, UNISA 2026
, UNISA | MNO2608 Occupational Hygiene: Assessment 3
Question 1: Hazard Investigation in the Sanding Section
The sanding section presents a classic occupational hygiene case in which a recognised car-
cinogen and asthmagen has been allowed to accumulate unchecked for years. Wood dust
is classified by the International Agency for Research on Cancer as a Group 1 carcinogen,
placed in the same category as asbestos and crystalline silica, with the strongest epidemio-
logical evidence pointing to sinonasal and nasopharyngeal cancer among hardwood workers
(IARC, 2012, cited in HSE Blog, 2026). The absence of an occupational hygiene survey for
three years, combined with visibly excessive airborne dust, poor housekeeping, and incon-
sistent respirator use, indicates that this exposure has never been anticipated, measured, or
controlled in line with recognised practice.
1.1 Identification and Classification of Workplace Hazards
Four distinct hazard categories can be identified in the sanding section, each requiring a
different control strategy.
Chemical hazard: airborne wood dust. Wood dust generated by sanding is a particulate
chemical hazard. Beyond its nuisance-dust properties, hardwood dusts such as oak, beech,
mahogany, walnut, birch, elm, and ash carry specific carcinogenic and asthmagenic potential,
while softwood dusts are more strongly associated with occupational asthma (OSHA, n.d.).
This is the hazard most directly implicated in the reported coughing and breathing difficulty.
Physical hazard: mechanical and particulate emission. Sanding equipment emits dust at
high velocity from spinning abrasive surfaces, and the machinery itself typically generates
noise levels that compound respiratory strain with hearing risk; both are physical agents
arising from the mechanical action of the process (OSHA, n.d.).
Safety hazard: poor housekeeping. Accumulated wood dust on floors and surfaces is a slip,
trip, and fire/explosion hazard. Settled combustible dust is itself used by hygienists as an
indicator of inadequate local exhaust ventilation (LEV) performance (Fransman et al., 2024).
Organisational/administrative hazard: absence of a hygiene programme. The lack of an
occupational hygiene survey for three years, together with inconsistent enforcement of respi-
rator use, reflects a systemic management failure rather than an isolated technical fault. This
is a hazard in its own right because it removes the feedback loop that would otherwise detect
and correct the technical failures above (Fransman et al., 2024).
Page 2 of 11
College of Science, Engineering and Technology
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
MNO2608: Occupational Hygiene
Assessment 3 | Semester 2, 2026
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
MNO2608
Module Code:
Occupational Hygiene
Module Name:
Workplace Hazard Investigation: Sanding
Essay Topic:
Section and Vehicle Spraying Workshop
Assessment 3
Assignment Number:
Semester 2, 2026
Semester:
September 2026
Due Date:
Submitted in partial fulfilment of the requirements for Occupational Hygiene, UNISA 2026
, UNISA | MNO2608 Occupational Hygiene: Assessment 3
Question 1: Hazard Investigation in the Sanding Section
The sanding section presents a classic occupational hygiene case in which a recognised car-
cinogen and asthmagen has been allowed to accumulate unchecked for years. Wood dust
is classified by the International Agency for Research on Cancer as a Group 1 carcinogen,
placed in the same category as asbestos and crystalline silica, with the strongest epidemio-
logical evidence pointing to sinonasal and nasopharyngeal cancer among hardwood workers
(IARC, 2012, cited in HSE Blog, 2026). The absence of an occupational hygiene survey for
three years, combined with visibly excessive airborne dust, poor housekeeping, and incon-
sistent respirator use, indicates that this exposure has never been anticipated, measured, or
controlled in line with recognised practice.
1.1 Identification and Classification of Workplace Hazards
Four distinct hazard categories can be identified in the sanding section, each requiring a
different control strategy.
Chemical hazard: airborne wood dust. Wood dust generated by sanding is a particulate
chemical hazard. Beyond its nuisance-dust properties, hardwood dusts such as oak, beech,
mahogany, walnut, birch, elm, and ash carry specific carcinogenic and asthmagenic potential,
while softwood dusts are more strongly associated with occupational asthma (OSHA, n.d.).
This is the hazard most directly implicated in the reported coughing and breathing difficulty.
Physical hazard: mechanical and particulate emission. Sanding equipment emits dust at
high velocity from spinning abrasive surfaces, and the machinery itself typically generates
noise levels that compound respiratory strain with hearing risk; both are physical agents
arising from the mechanical action of the process (OSHA, n.d.).
Safety hazard: poor housekeeping. Accumulated wood dust on floors and surfaces is a slip,
trip, and fire/explosion hazard. Settled combustible dust is itself used by hygienists as an
indicator of inadequate local exhaust ventilation (LEV) performance (Fransman et al., 2024).
Organisational/administrative hazard: absence of a hygiene programme. The lack of an
occupational hygiene survey for three years, together with inconsistent enforcement of respi-
rator use, reflects a systemic management failure rather than an isolated technical fault. This
is a hazard in its own right because it removes the feedback loop that would otherwise detect
and correct the technical failures above (Fransman et al., 2024).
Page 2 of 11
