How must the construction of the ventilated cap or collar affect force transmission?

In the context of a ventilated cap or collar, the construction should be designed to ensure that the force applied does not transmit a blow to the valve. This is crucial for the integrity and functionality of the valve, as any sudden impact could lead to malfunction or damage. By preventing the direct transmission of force to the valve, the ventilated cap or collar acts as a protective shield, absorbing or dissipating the force. This ensures that the valve operates smoothly and remains intact during normal usage and under various conditions.

Regarding the other options, amplifying the force or redirecting it away from the cylinder could lead to unintended consequences for the valve's performance, and equalizing pressure on the valve does not address the concern of force transmission directly. Hence, the correct approach focuses on avoiding any blow to the valve, maintaining its operational integrity.