ACI Environmental & Worker Safety 5

Question 1

During a confined space entry to finish concrete in a deep vault, which atmospheric hazard must be tested FIRST before entry?

Accepted Answer

Oxygen level, followed by flammable gases, then toxic contaminants

Answer

Toxic contaminants first, then oxygen

Answer

Flammable gases only

Answer

Carbon dioxide concentration only

Question 2

What best management practice (BMP) must be installed downslope of concrete work to prevent alkaline runoff from leaving a construction site?

Accepted Answer

Concrete washout containment berms and sediment controls such as silt fences

Answer

Speed bumps to slow vehicle traffic

Answer

Temporary asphalt pavement

Answer

Wooden boardwalks

Question 3

Which standard sets the minimum requirements for the design and testing of eye and face protection used when handling wet concrete?

Accepted Answer

ANSI/ISEA Z87.1

Answer

ANSI Z89.1

Answer

ASTM F2413

Answer

NFPA 70E

Question 4

A finisher is using a gas-powered concrete saw in a partially enclosed area. Which atmospheric hazard is the primary concern?

Accepted Answer

Carbon monoxide buildup from combustion exhaust

Answer

Silica dust only

Answer

Nitrogen dioxide from rain reaction

Answer

Ozone from UV exposure

Question 5

When curing compounds are sprayed on fresh concrete, which PPE is MOST critical to prevent respiratory sensitization?

Accepted Answer

A supplied-air respirator or NIOSH-approved organic vapor respirator with P100 filter

Answer

Safety glasses only

Answer

Standard N95 dust mask

Answer

Hearing protection

Question 6

What is the maximum noise exposure level (dBA) permitted by OSHA for an 8-hour workday without hearing protection?

Accepted Answer

90 dBA

Answer

85 dBA

Answer

100 dBA

Answer

80 dBA

Question 7

Which form of silicosis is associated with very high silica exposures over a short period (weeks to 5 years) and carries the worst prognosis?

Accepted Answer

Accelerated silicosis

Answer

Chronic silicosis

Answer

Complicated silicosis

Answer

Pleural silicosis