At a glance
| Substance | Boiling point (approx.) | Filter type | AirGuard Pro filter |
|---|---|---|---|
| Methanol | 65 °C (just below) | AX (not in the range) | none in the range |
Methanol: what matters
Methanol boils at about 65 °C, just below the limit. Type A is therefore not suitable, an AX filter is needed. The AirGuard Pro range has none. With mixtures containing methanol the lowest boiling point counts.
Suitability by boiling point is explained in the guide Respiratory protection for solvents.
Mask and limits
Under DGUV Rule 112-190 the half mask AG360 is permitted up to 30 times the workplace exposure limit, the full-face mask AG700 up to 400 times. The workplace exposure limit of the substance is given in TRGS 900. The gas filter has its own limit as well: class 1 applies up to 0.1 vol.%, that is 1,000 ml/m³. The stricter value applies.
| Class | Maximum | AirGuard Pro |
|---|---|---|
| Class 1 | 0.1 % by volume (1,000 ml/m³) | AGA1E1, AGABEKK1, AGABEKK1P3 (bayonet) |
| Class 2 | 0.5 % by volume (5,000 ml/m³) | AGA2E2, AGABEK2, AGABEK2P3 (RD40) |
| Class 3 | 1.0 % by volume (10,000 ml/m³) | not in the range |
- Unknown concentration, incident, release: Without a known concentration there is no justified filter choice.
- Oxygen not certain: Filters supply no oxygen, the instructions for use name at least 19.5 vol.%. In tanks, pits and confined spaces an isolating device is needed.
- Filter replacement: Replace gas filters according to a fixed schedule, at the latest at odour, taste or irritation. See Changing filters.
How to proceed
- Read the safety data sheet: components (section 3), boiling point (section 9), workplace exposure limit (section 8).
- Determine type and class: The type depends on the substance, the class on the concentration.
- Risk assessment with the occupational safety specialist, see Respiratory protection duties.
- Check the face seal: a beard or sideburns prevent protection, see Face seal and beards.
If you know substance and concentration, the respirator finder leads to the matching combination. All substances at a glance: Substance directory.
Frequently asked questions
Which filter protects against methanol?
AX filters are intended for it, not type A. The AirGuard Pro range has no AX filter. Contact us or the occupational safety specialist.
Is an FFP mask enough against methanol?
No. FFP masks hold back only particles, no gases and vapours. You need a gas or combination filter.
Where do I find the limit value for methanol?
In TRGS 900 (workplace exposure limits) and in section 8 of the safety data sheet. More substance data is in the GESTIS substance database.
Sources
- GESTIS substance database (DGUV, IFA, Germany)
- DGUV Rule 112-190 “Use of respiratory protective devices” (Germany), November 2021 edition
- TRGS 900 Workplace exposure limits (BAuA, Germany)
- Hazardous Substances Ordinance (GefStoffV, Germany)
- Instructions for use and data sheets of the AirGuard Pro products
