Answer:
Both technicians are correct
Step-by-step explanation:
For the safety and economical operation of any vehicle, there's an optimum pressure at which the vehicle's tires must be inflated. It is therefore very important to find the optimum pressure that is right for your vehicle.
On the sidewall of a tire, there's a pressure imprinted on it, usually below the bold letters of the manufacturer's name. This is the maximum pressure needed for a tire to carry its maximum load. It's usually called "cold pressure" because that's when tires are expected to be filled i.e when they're cold. However, this is not to say that the tires should be filled to this maximum pressure, it is discouraged in fact. When a tire is inflated to the maximum pressure, the lifespan of the tire decreases, a blowout can also occur.
There's usually a sticker on the driver's door, on which states the optimum or recommended pressure for a car's tires. This can also be found in the owner's manual, the fuel door or on the trunk lid.
This recommended pressure indicates the minimum amount of air pressure a car needs to carry its maximum load. At a lower pressure, the tires could undergo premature wear as a result of tire overloading or excess flexing.
Tires should be inflated to the recommended air pressure for safety and economical operation of a vehicle.