CIH Certified Industrial Hygienist (CIH) MCQ 4

Question 1

Which dermal exposure route is most significant for organophosphate pesticide absorption in agricultural workers?

Accepted Answer

Dermal absorption through intact skin

Answer

Dermal absorption through intact skin is the predominant route of organophosphate exposure for field workers due to large surface area contact with residues.

Question 2

The Threshold Limit Value for a mixture of chemicals with similar health effects is calculated using which approach?

Accepted Answer

An additive formula: sum of (Ci/TLVi) must not exceed 1

Answer

For chemicals with additive effects, the mixture formula Σ(Ci/TLVi) ≤ 1 must be satisfied to ensure the combined exposure is acceptable.

Question 3

Which instrument is most appropriate for measuring real-time concentrations of combustible gases to assess explosion risk?

Accepted Answer

Catalytic bead combustible gas detector (CGI)

Answer

Catalytic bead combustible gas indicators (CGIs) measure % LEL in real time and are the standard tool for explosion risk assessment.

Question 4

A worker develops metal fume fever after welding on galvanized steel. The causative agent is fumes of:

Accepted Answer

Zinc oxide

Answer

Metal fume fever is most commonly caused by inhalation of freshly generated zinc oxide fumes from welding or cutting galvanized (zinc-coated) steel.

Question 5

Which control measure hierarchy level does administrative rotation of workers through high-noise areas represent?

Accepted Answer

Administrative controls

Answer

Rotating workers to limit their time in high-noise areas is an administrative control, the third tier in the hierarchy of controls.

CIH - Certified Industrial Hygienist Exam Practice Test

CIH - Certified Industrial Hygienist Exam Practice Test

CIH Certified Industrial Hygienist (CIH) MCQ 4