Japan's Ministry of Health, Labour and Welfare (MHLW) has published indoor air quality guidelines for 13 volatile organic compounds, including formaldehyde, toluene, xylene, and ethylbenzene. These guidelines apply to newly built or renovated buildings and are increasingly referenced in building handover documentation and facility management contracts.
Which compounds are covered by the MHLW guidelines? ¶
The 13 compounds in the current MHLW guidelines include formaldehyde (guideline value: 100 micrograms per cubic metre), toluene (260 micrograms per cubic metre), xylene (200 micrograms per cubic metre), ethylbenzene (3,800 micrograms per cubic metre), styrene (220 micrograms per cubic metre), and eight others. Formaldehyde is the most commonly exceeded compound in newly renovated spaces, particularly where urea-formaldehyde adhesives have been used in flooring or cabinetry.
How passive sampler testing works ¶
Passive samplers are small diffusion tubes that absorb VOCs from the air over a defined exposure period, typically 8 hours for the MHLW standard measurement. We post the sampler to your address with instructions for deployment. You place it in the room to be tested, leave it for the specified period, seal it, and return it by post. Laboratory analysis by GC-MS is completed within 10 working days of receipt.
When to test ¶
The MHLW recommends testing after construction or renovation work is complete and before regular occupancy begins. Summer is a relevant season for this: higher temperatures increase VOC off-gassing from adhesives and finishes, so measurements taken in summer represent a realistic worst-case for the year. Building managers who test in summer and meet the guidelines can be confident the space will be within limits in cooler months.
What the report includes ¶
The Indoor Air VOC Screen report lists the measured concentration of each target compound alongside the MHLW guideline value, with a clear indication of whether the result is above or below the guideline. For compounds that exceed the guideline, we include a brief note on likely sources and ventilation recommendations. The report is suitable for inclusion in building handover documentation.
The Indoor Air VOC Screen is priced at ¥41,000. During summer 2026, it is available as a free add-on with any material or water quality panel booking made before 30 September. Contact us at lab@driftcorelab.com to arrange.