# MSL Floor Life Reference Table (J-STD-020 and J-STD-033)

> Source: https://netray.co/tools/msl-floor-life-reference-j-std-033
> Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems.
> Section: Free Tools

## Short answer

Searchable table of moisture sensitivity levels 1 to 6 with floor life, soak conditions and the key dry pack handling rules from J-STD-033.

## Category

electronics

## Industry

Electronics Manufacturing

## Audience

- Process engineer
- SMT operator
- Electronics buyer
- Quality engineer

## Tool

**Kind:** worksheet

**Mode:** reference

**Columns:**

#### Item

**Key:** item

**Type:** text

#### Group

**Key:** group

**Type:** text

#### Floor life or requirement

**Key:** requirement

**Type:** text

#### Notes

**Key:** notes

**Type:** text

**Rows:**

**Item:** MSL 1

**Group:** Level

**Requirement:** Unlimited at 30 C / 85% RH or less

**Notes:** Soak for classification: 168 h at 85 C / 85% RH. No dry pack needed.

**Item:** MSL 2

**Group:** Level

**Requirement:** 1 year at 30 C / 60% RH or less

**Notes:** Soak: 168 h at 85 C / 60% RH. Dry pack required.

**Item:** MSL 2a

**Group:** Level

**Requirement:** 4 weeks at 30 C / 60% RH or less

**Notes:** Soak: 696 h at 30 C / 60% RH.

**Item:** MSL 3

**Group:** Level

**Requirement:** 168 hours at 30 C / 60% RH or less

**Notes:** Soak: 192 h at 30 C / 60% RH. Very common for BGAs and QFPs.

**Item:** MSL 4

**Group:** Level

**Requirement:** 72 hours at 30 C / 60% RH or less

**Notes:** Soak: 96 h at 30 C / 60% RH.

**Item:** MSL 5

**Group:** Level

**Requirement:** 48 hours at 30 C / 60% RH or less

**Notes:** Soak: 72 h at 30 C / 60% RH.

**Item:** MSL 5a

**Group:** Level

**Requirement:** 24 hours at 30 C / 60% RH or less

**Notes:** Soak: 48 h at 30 C / 60% RH.

**Item:** MSL 6

**Group:** Level

**Requirement:** Time on label (TOL)

**Notes:** Must be baked before use and reflowed within the time printed on the label.

**Item:** Floor life clock start

**Group:** Handling

**Requirement:** Starts when the moisture barrier bag is opened

**Notes:** Also starts if parts are removed from dry storage or the bag seal is found breached.

**Item:** Sealed bag shelf life

**Group:** Handling

**Requirement:** At least 12 months at 40 C / 90% RH or less

**Notes:** Measured from the bag seal date printed on the label.

**Item:** Humidity indicator card

**Group:** Handling

**Requirement:** Read immediately after opening the bag

**Notes:** If the indicator exceeds the stated threshold, follow the bake requirement before reflow.

**Item:** Dry pack contents

**Group:** Handling

**Requirement:** Desiccant, humidity indicator card and moisture barrier bag

**Notes:** Bag carries a caution label with MSL, floor life, peak reflow temperature and seal date.

**Item:** Reflow temperature

**Group:** Handling

**Requirement:** Do not exceed the peak body temperature on the label

**Notes:** Classification is tied to a peak temperature, often 245 C, 250 C or 260 C depending on package size.

**Item:** Resetting floor life

**Group:** Handling

**Requirement:** Bake per the J-STD-033 bake tables, or return to dry storage

**Notes:** Bake time depends on package body thickness, prior exposure and bake temperature. Use the current standard tables.

**Item:** Dry cabinet storage

**Group:** Handling

**Requirement:** At or below 10% RH

**Notes:** Parts held in a qualified dry cabinet can pause the floor life clock only as allowed by the standard.

**Item:** Resealing a bag

**Group:** Handling

**Requirement:** Fresh desiccant, fresh humidity indicator card, vacuum seal

**Notes:** Record the new seal date and remaining floor life on the label or in your MES.

**Item:** Accumulated exposure

**Group:** Handling

**Requirement:** Track every interruption in your floor life log

**Notes:** Add time out of the bag across loading, line stoppages and rework passes.

**Notes:** Summary reference only, not a substitute for the current IPC/JEDEC J-STD-020 and J-STD-033 documents. Always follow the label on the actual bag and your customer or quality system requirements.

## Content

**Intro:** Moisture sensitive devices crack, delaminate or pop when absorbed moisture flashes to steam in reflow. The MSL rating on the bag label tells you how long a part can sit on the shop floor. This table puts the levels and the key handling rules in one searchable page.

**Sections:**

#### How to use the table

**Body:** Search for the level printed on your bag, such as MSL 3, to see its floor life and classification soak. Then use the handling rows to answer the questions that come up on the line: when the clock starts, what the humidity card means, how to reseal and how to reset exposure by baking. Export it to PDF and post it near the SMT feeder prep area, or to Excel to build your own floor life rules for MES or the kitting process.

#### What the standards cover

**Body:** IPC/JEDEC J-STD-020 defines how a device is classified: it is preconditioned with a moisture soak at a stated temperature and humidity, taken through reflow, and checked for damage. J-STD-033 covers what you do with it afterward: packing, labeling, shelf life, floor life, baking and re-bagging. Floor life numbers here assume ambient at or below 30 C and 60% relative humidity. Hotter or more humid factory air shortens real tolerance, and a few percent RH matters more than most people expect.

**Bullets:**

- MSL 1 parts need no dry packing.
- MSL 2 to 5a parts need dry packing and a tracked floor life.
- MSL 6 parts must be baked before every use.

#### Common mistakes and ERP notes

**Body:** The usual failures are not knowing when the bag was opened, leaving partially used reels out overnight, and baking without recording the new baseline. Reels split across lines or shifts are especially risky. In ERP, store MSL level and floor life as item attributes, and in MES or a simple log record bag open time, time out and bake events per reel or tray. A reel that has run out of floor life should be quarantined with a nonconformance record, not just pushed through.

**Bullets:**

- Do not bake tape and reel packaging unless the packaging is rated for the bake temperature.
- Repeated bakes can oxidize leads and hurt solderability, so limit them.
- Label every returned reel with remaining floor life.

**Cta:** If you need MSL and floor life tracked against your ERP lots and reels, we can build a read-only view or a controlled log over your data. That is optional and the table above is complete on its own.

**Faq:**

#### What is the difference between MSL and floor life?

**Answer:** MSL is the classification level, 1 to 6, assigned by the component maker. Floor life is the number of hours or days the part may be exposed to factory air at 30 C and 60% RH before it must be reflowed or re-dried. Each MSL has a defined floor life.

#### Does floor life reset when I put parts back in a dry cabinet?

**Answer:** Only under the conditions the standard allows, typically a qualified dry cabinet or a bake. Simply returning parts to a normal storage shelf does not reset the clock. Use the bake and dry storage rules in the current J-STD-033 and keep a record.

#### What does MSL 6 time on label mean?

**Answer:** MSL 6 parts must be baked before mounting and then reflowed within the time printed on the label after removal from the bag. There is no standard floor life number, so the label for that particular part is the authority.

#### Do I need to track floor life for MSL 1?

**Answer:** No. MSL 1 parts are not moisture sensitive at 30 C and 85% RH, so there is no floor life limit. You should still follow ESD handling and storage rules, and check that the label really says MSL 1.

## Search terms

msl floor life chart, j-std-033 floor life, moisture sensitivity level table, msl 3 168 hours, msl levels explained, smd moisture sensitive handling, j-std-020 msl classification, floor life after opening bag

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