UNIVERSITY OF SOUTH AFRICA (UNISA)
College of Engineering, Science and Technology
⋄
Occupational Hygiene: Recognition,
Evaluation and Control
Assignment 3 — Semester 2, 2026
⋄
Module Code: MNO2608
Module Name: Occupational Hygiene
Assignment No.: Assignment 3
Due Date: September 2026
Semester: Semester 2, 2026
Submitted in partial fulfilment of the requirements for MNO2608: Occupational Hygiene
at the University of South Africa.
, UNISA | MNO2608 Occupational Hygiene: Assignment 3
Question 1: Wood Dust Exposure in the Sanding Section
The sanding section of the furniture factory presents a classic occupational hygiene problem:
a physical health hazard generated continuously by the work process itself, compounded by
weak administrative control and inconsistent use of personal protective equipment. Wood
dust becomes hazardous once particles from sanding operations become airborne, and it
is associated with eye, nose and throat irritation, dermatitis, and long- and short-term respi-
ratory effects including reduced lung capacity and occupational asthma (OSHA, 2024). The
absence of any occupational hygiene survey in three years means management has been
operating without objective exposure data, which is itself a governance failure that this inves-
tigation must correct.
1.1 Identification and Classification of Workplace Hazards
Occupational hygiene classifies hazards into five broad categories: physical, chemical, biolog-
ical, ergonomic and psychosocial. Applying this framework to the sanding section identifies
the following hazards, each carrying a five-mark weighting that requires both identification
and justification rather than a bare list.
The primary hazard is a chemical/physical hazard in the form of airborne wood dust. Dust
generated by sanding is a particulate contaminant that behaves as an inhalation hazard once
it becomes airborne in the breathing zone of workers, and the excessive dust observed during
the inspection confirms that generation is exceeding whatever local control exists. Wood
dust is classified by the International Agency for Research on Cancer as a substance associ-
ated with cancer of the nasal cavity and paranasal sinuses, in addition to irritant and allergic
effects (Barcik and Gasparik, 2019).
A second hazard is poor housekeeping, which functions as a hazard multiplier rather than
a hazard in its own right. Accumulated dust on floors, ledges and equipment represents a
secondary source of re-entrainment into the air whenever it is disturbed, and dry sweeping in
particular resuspends settled particles that a worker has already been exposed to once. Good
housekeeping in a wood dust environment requires wet cleaning methods or vacuum extrac-
tion rather than dry sweeping precisely because sweeping recreates the airborne exposure
the extraction system was meant to remove (MSC Industrial Supply Co., 2023).
A third hazard is inadequate and inconsistently used respiratory protective equipment. This
Page 1 of 12
College of Engineering, Science and Technology
⋄
Occupational Hygiene: Recognition,
Evaluation and Control
Assignment 3 — Semester 2, 2026
⋄
Module Code: MNO2608
Module Name: Occupational Hygiene
Assignment No.: Assignment 3
Due Date: September 2026
Semester: Semester 2, 2026
Submitted in partial fulfilment of the requirements for MNO2608: Occupational Hygiene
at the University of South Africa.
, UNISA | MNO2608 Occupational Hygiene: Assignment 3
Question 1: Wood Dust Exposure in the Sanding Section
The sanding section of the furniture factory presents a classic occupational hygiene problem:
a physical health hazard generated continuously by the work process itself, compounded by
weak administrative control and inconsistent use of personal protective equipment. Wood
dust becomes hazardous once particles from sanding operations become airborne, and it
is associated with eye, nose and throat irritation, dermatitis, and long- and short-term respi-
ratory effects including reduced lung capacity and occupational asthma (OSHA, 2024). The
absence of any occupational hygiene survey in three years means management has been
operating without objective exposure data, which is itself a governance failure that this inves-
tigation must correct.
1.1 Identification and Classification of Workplace Hazards
Occupational hygiene classifies hazards into five broad categories: physical, chemical, biolog-
ical, ergonomic and psychosocial. Applying this framework to the sanding section identifies
the following hazards, each carrying a five-mark weighting that requires both identification
and justification rather than a bare list.
The primary hazard is a chemical/physical hazard in the form of airborne wood dust. Dust
generated by sanding is a particulate contaminant that behaves as an inhalation hazard once
it becomes airborne in the breathing zone of workers, and the excessive dust observed during
the inspection confirms that generation is exceeding whatever local control exists. Wood
dust is classified by the International Agency for Research on Cancer as a substance associ-
ated with cancer of the nasal cavity and paranasal sinuses, in addition to irritant and allergic
effects (Barcik and Gasparik, 2019).
A second hazard is poor housekeeping, which functions as a hazard multiplier rather than
a hazard in its own right. Accumulated dust on floors, ledges and equipment represents a
secondary source of re-entrainment into the air whenever it is disturbed, and dry sweeping in
particular resuspends settled particles that a worker has already been exposed to once. Good
housekeeping in a wood dust environment requires wet cleaning methods or vacuum extrac-
tion rather than dry sweeping precisely because sweeping recreates the airborne exposure
the extraction system was meant to remove (MSC Industrial Supply Co., 2023).
A third hazard is inadequate and inconsistently used respiratory protective equipment. This
Page 1 of 12
