Humidity Indicators (HIC) and MSL Level Control
How to read an indicator
The points are calibrated to percentages of relative humidity. It is read the point with the highest percentage changeThat is the level to which the content was exposed.
- No points changed. The packaging maintained the barrier and the component retains its shelf life.
- The low point changed. There was moisture, but below the critical threshold. The desiccant was checked and resealed.
- The high point changed. The component exceeded its storage condition. It is not assembled: it is baked first.
The change is irreversible, and therein lies its value: the indicator doesn't say how the packaging is now, it says where it passed. A package that was left in a yard for three days and then cooled down again looks the same as one that never left the warehouse; the indicator is what distinguishes them.
The MSL level: how much can be outside the packaging
Each moisture-sensitive component brings a MSL level assigned according to IPC/JEDEC J-STD-020. That number tells you how long it can stay out of the sealed packaging before it needs to be baked. It's a useful chart to keep handy:
- MSL 1 — apartment living unlimited, at ≤30 °C and 85% HR.
- MSL 2 — 1 year.
- MSL 2a — 4 weeks.
- MSL 3 — 168 hours (7 days).
- MSL 4 — 72 hours.
- MSL 5 — 48 hours.
- MSL 5a — 24 hours.
- MSL 6 — baking required before use.
From level 2a to 6, the reference condition is ≤30 °C and 60% relative humidity.
The clock starts ticking when the bag is opened, not when the material arrives. An MSL 3 opened on a Monday expires the following Monday; an MSL 5a lasts one shift. That's why the indicator and the opening log go hand in hand: without knowing when it was opened and what condition it was in, the MSL level is useless data.
The standard that defines handling—storage, transport, when to bake and how to reseal—is IPC/JEDEC J-STD-033.
What we handle
Have line indicators in different ranges and presentations, and we also work under specification: if your internal regulations or your client require a specific configuration of points, it is quoted.
They can be ordered in two ways:
- Loose consumable, so that you can integrate it into your own packaging process.
- Complete packaging as a serviceWe seal the component with a bag, desiccant, and indicator, and deliver it to you ready.
They are used in electronics to protect semiconductors and integrated circuits, in the storage of SMT components, and in laboratories or research centers where the custodial status must be certified.
The indicator alone does not protect anything.
This is the most common mistake: buying indicators and putting them in any old bag. The indicator is the witness of the system, not the system itself. For it to work, four things are needed together:
- ESD bag with moisture barrier. Without a barrier, the indicator is only measuring the air in the warehouse.
- Silica gel desiccant. It absorbs incoming moisture. The amount depends on the bag's area and the expected storage time.
- The indicator. The witness to whether the system held up.
- The sealing, with vacuum when applicable.
All four are ordered together in ESD consumables.
Request a quote for the consumable or the complete packaging
Tell us the MSL level of your components, the package size and the expected storage time, and we will suggest the appropriate combination of bag, desiccant and indicator. Contact us.
What to do when the indicator shows exposure
The indicator warns, it doesn't correct. If the high point has changed, there are three steps, and none are skipped:
- Do not mount the component. The heat from the reflow converts the absorbed moisture into vapor inside the encapsulation, causing internal delamination and microcracks that are not visible.
- Bake In accordance with J-STD-033. Time depends on the MSL level and the packaging. We offer this as a service. baking and drying.
- Reseal with new desiccant and indicator, in a barrier bag. The used indicator is not reused.
Buy humidity indicators online
The 3, 4, and 6-point Humidity Indicator Cards (HICs) are in the SBC Store packaging consumables, For example, the 3-point HIC and the 6-point HIC, Price per unit, VAT included, and shipping throughout Mexico. desiccant and the barrier bags They are in the same store.
Frequently Asked Questions
What does it mean for a component to be MSL 3?
That may be outside the sealed packaging 168 hours —seven days— at 30°C and 601% relative humidity before baking is required. The timer starts when the bag is opened.
Can the indicator be reused?
No. The color change is irreversible, and that's precisely what makes it reliable. It's replenished every time the package is resealed.
What happens if I install a component with the indicator changed?
The risk is internal delamination of the encapsulation during reflow. The defect is not visible, passes visual inspection, and only appears later in the field as an intermittent failure.
Does it work for assembled boards, not just for loose components?
Yes. A stored PCBA also absorbs moisture, and before reworking it, it must be dried, for the same reason.
Do they handle special configurations?
Yes. We have line indicators in various ranges and presentations, and we work to specification when a specific configuration is needed.
Do they sell just the indicator or the complete package?
Both: the loose consumable, or the complete sealed package as a service.
Where do they deliver?
From Guadalajara (Tlaquepaque, Jalisco) and Querétaro (El Colorado). Both plants provide national coverage and we can export.
Do you have components with the indicator already changed?
This is the most common problem and it has a solution: it's baked according to J-STD-033 and resealed. Send us the part number and MSL level and we'll tell you the drying time and what can be recovered. Contact us.