PCV (positive crankcase ventilation), the first smog device mandated to be installed in cars beginning in 1964. PCV captures blowby gases escaping into the crankcases below the pistons and redirects the toxic blowby gases back into the intake manifold through a series of large rubber hoses and a pulsing valve. New PCV hoses are airtight and works well until several years later when the rubber hoses tend to lose it pliabilty (sealing quality) at the ends . I suggest that all new cars more than 2 or 3 years old should be required to install clamps to tighten all the ends of the PCV related rubber hoses to ensure that the PCV system still functions as effectively as when new. This may add costs to the annual smog check but it can save us far more in reduced pollution related health costs. Blowby gases escaping through slightly loose PCV hoses from high atmospheric pressures inherent in the crankcases at high speeds is not to be taken lightly. The pulsing PCV valve cannot capture all of the blowby gases because most of the blowby gases willl seek less resistance through the loose PCV hose end connections and escaping there before it goes through the PCV pulsing valve. The pulsing PCV valve is not capable of high volume due to its restricted design to preserve the vaccuum levels needed in the intake manifold to facillate air / gas mixutre efficiently. it is of utmost importance for EPA to revisit present PCV technology and review for any design improvements that will ensure that PCV system be more reliable than what we have today which is an embrassment . Our PCV technology remains unchanged since 1964. As matter of factly, about half of our smog still comes from blowby gases escaping through worn out PCV hose connections that are never tightened by smog check technicians . it is not a requirement at all except for visual inspection. There is still no test to see if existing PCV hose connections are tight connected in each inspected car. I tightened PCV hose connections voluntarily myself.. Frankly speaking , I am somewhat surprised that EPA still has not paid enough attention to the PCV hose connections in our exisitng car fleet . It is a rather shocking omission on EPA's own behalf.. I hope that the EPA will pay closer attention then.