How many half-value layers must be added to the primary beam to reduce its intensity to less than 20 percent of its original value?

You have just arrived on the scene of a motor vehicle collision in which a compact car was struck from behind by a delivery truck. The driver of the delivery truck is standing outside his vehicle talking to police when you arrive, but the driver of the car is still seated in the driver's seat. You have noted moderate damage to the rear of the car. For which of the following injuries should you

have the highest level of suspicion? A) Fractures of the lower extremities B) Abdominal injuries C) Chest injury D) Neck injury

What is the primary concern in determining placement of an aerial apparatus at a commercial or industrial structure?

A. Rescue B. Collapse C. Ventilation D. Exposures