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How to Protect the PCBs
1114 1 Jan 04.2022, 13:47:24

In our daily life, it is manufacturers who mark the shelf life of foods. They are responsible for the quality of the foods and should follow any guarantees about the quality within the shelf life. Things happen the same with the PCB industry.

PCB Storage Conditions

Different from other productions, the storage condition of PCB requires a strict restriction on air and water contact. First, the vacuum seal of PCB boards can not be damaged, and operators should coat the box with a layer of bubble film. The bubble film has good water absorption capability and plays a good role in moisture-proof function. Also, placing some moisture-proof beads can achieve this purpose to some extent.


Figure 1 Importance of water-proof PCB coating

After sealing, the box should be stored off the ground and kept in a dry and ventilated place away from direct sunlight. Secondly, temperature and relative humidity control are essential within the standard range based on factory regulation. The storage time of PCB is not only related to its capability and the technology of manufacturers, but also it is correlated with producing place. 

When it comes to the PCB shelf time, PCB baking time, and PCB baking temperature, people should consider case by case what are the PCB manufacturer’s capability and technology? Where are they from? And, what’s the weather at that place?


Figure 2 PCB storage machine in PCBgogo

In the manufacturing process, it is premier for PCB manufacturers to apply a layer of three-proof paint on PCB boards in a long storage time. The role of the three-proof painting can prevent moisture, dust, and oxidation. In this way, the PCB shelf life will increase to 9 months. For example, the OSP PCB and gold immersion PCB generally have a shelf life of 6 months after packaging, while it will be three months if the PCB doesn’t use surface finish.

The shelf time of the PCB is related to the surface finish. PCB that taken Immersion gold and electroplated gold as a surface finish has the longest shelf time. Their storage time will last for two to three years under constant temperature and humidity conditions. High-standard PCB storage conditions benefit the service life of the electronic machine.

PCB Package

After the product inspection, the PCB board is vacuum packaged and stored for shipment. But why do manufacturers want PCB vacuum packaging? The following will briefly introduce the PCB storage methods and their shelf life.

1. Why should the PCB board be vacuum-packed

Although this is a small question in PCB manufacture, many of them still attach great importance to the method of PCB package. Once the PCB package seal improperly, the surface of the gold, tin, and pad parts will be oxidized and affect the soldering process, which is not conducive to production.


Figure 3 PCB vacuum-packed process 

2. How to store PCB boards

Bare PCB boards cannot directly contact air and water. As a result, the PCB vacuum package must not be broken. After adopting moisture measures, PCB manufacturers will classify, place the label, and seal the box. The box must be saved in a dry and ventilated place with partition walls and off the ground where avoiding sunlight. The best temperature and humidity should be at 23±3℃, 55±10%RH. 

Under such circumstances, PCB boards with the surface finish, such as immersion gold (ENIG), HASL, and immersion silver (Ag) can generally be stored for six months. And PCB boards with the surface finish, such as immersion silver (Ag), ENIG, and OSP can only be stored for three months in general.

The Storage Condition of PCB in PCB Assembly Process

1. Storage after SMT processing

Usually, the SMT boards will be placed in the factory about 1-3 days after processing, sometimes longer. For common PCB boards materials, the temperature is at 22°C~30°C, and the humidity is between 30%RH~60%RH, placed on an anti-static rack.


Figure 4 PCBA anti-static rack

However, the PCB board of the OSP process needs to be stored in a constant temperature and humidity cabinet. The temperature and humidity requirements are more stringent for OSP PCB. They should be soldered within 24 hours. Otherwise, the pads are easily oxidized.

2. Storage condition after PCBA testing

Generally, PCB will be quickly assembled after testing. In this case, the temperature and humidity are well controlled, and there is no need for too many requirements. However, if long-term storage is required, it can be coated with conformal paint and vacuum-packed. The ambient temperature is between 22~28℃, and the relative humidity is 30~60%RH.

Surface Finish


Storage Condition

Shelf Time

HASL(Hot air solder leveling)




Package:Vacuum (Desiccant included)

12 months

Immersion gold




Package:Vacuum (Desiccant included)

6 months

Immersion sliver (Ag)




Package:Vacuum (Desiccant included)

3 months





Package:Vacuum (Desiccant included)

3 months

Additionally, PCB and PCBA manufacturers are equipped better storage environment than general workshops. As a result, PCBA outsourcing is possible to leverage it into a kind of saving-money method for small companies, or middle-scale shops.

The Advantages of Choosing a PCBA Manufacturer

1. Fast Production Speed - Time-Saving

As we all know, small electronic companies have defects in production - It is difficult for them to guarantee the production time. If the PCBA products cannot finish on schedule, the company’s products would be affected. As a result, PCBA outsourcing is the greatest option for increasing production efficiency and ensuring timeliness. Furthermore, as an electronics firm, the objective should not be to participate in manufacturing but rather to grow the business and extend the client base in order to receive more orders and earn larger profits. 

Advanced equipment and expert employees are used by professional PCBA processing companies. They can assist small businesses in quick-turn manufacturing to support their business growth and help them establish a positive market reputation.

2. Maintain Productions Consistency - Low Failure Rate

Because thePCB assembly line needs to have a suitable environment, most electronics companies are unable to maintain the quality if they manufacture their own PCB assembly products. Besides, Investment in this environment necessitates a large sum of money, which is difficult for small businesses to get. They will inevitably select the whole manual production line. Under this premise, the production environment cannot be guaranteed, which will finally impact the quality of products. PCBA manufacturers will use the most advanced automatic equipment for production to ensure high-quality and cost-effective PCB assembly products. 

3. High-quality Components - Quality Guarantee

Using high-quality parts is the simplest way to ensure circuit board quality. It is impossible to obtain the highest quality parts at the lowest price if the electronics company is small and the order quantity is limited. The profit margin will be reduced as a result of this. As to a company, cooperating with a good reputation PCB and PCB assembly manufacturers helps ensure their interest. 

4. Cost Savings - The Most Considerable Reason

The primary reason why most electronics companies select PCBA outsourcing is cost. We all know it has something to do with product quality as well as a market competitive advantage. The larger the competitive advantage, the cheaper the price with better quality. On the other hand, even if the quality is superb, if the price is too high, the company will lose a lot of clients. As a result, the most significant advantage of PCBA outsourcing is its low cost. Companies may better invest in business expansion by outsourcing PCB assembly since they don't have to worry about PCB storage environment, technology, equipment, people investment, raw material acquisition, warehouse management, and so on.


At last, excellent PCB and PCB assembly manufacturers can achieve this effect efficiently. Therefore, when choosing a PCB and PCB assembly manufacturer, people must pay attention to whether the manufacturer has a high-quality guarantee, fabrication ability, production scale, and professionalism. 

PCBgogo has over 10 years of experience designing and fabricating them. From 1 piece to small-bacth PCB and PCB assembly manufacturing, PCBgogo expertise gives you the highest quality printed circuit boards you need and the quick turnaround time you demand. All the products meet UL certification and RoHS & REACH Standards. With 4 own factories in China, PCBgogo has the ability to manufacture prototypes as fast as 24 hours.


Figure 5 PCB vacuum sealing from PCBgogo

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