Category

Hazardous materials

Gas masks for halogens

Halogen gases or vapors

Gas masks for organic compounds

Organic compound vapors

Gas masks for carbon monoxide

Carbon monoxide

Gas masks for ammonia

Ammonia

Gas masks for sulfur dioxide

Sulfur dioxide

Type

Form and scope of application

Front or back mounted type gas mask

It is composed of a canister, a breathing tube, inhalation valve(s), a facepiece, exhalation valve(s), and head harness. Clean air filtered by the canister is inhaled from the inhalation valve(s) through the breathing tube , and exhaled air is exhausted from the exhalation valve(s) to outside atmosphere, and is used in the atmosphere where the concentration of the gases or vapors is less than 2 % (3 % for ammonia).

Chin -style gas mask

It is composed of canister(s), inhalation valve(s), a facepiece, exhalation valve(s) and head harness. Clean air filtered by the canister(s) is inhaled from the inhalation valve(s), and exhaled air is exhausted from the exhalation valve(s) to outside atmosphere, and is used in the atmosphere where the concentration of the gases or vapors is less than 1 % (1.5 % for ammonia).

Chemical cartridge respirator

It is composed of chemical cartridge(s), inhalation valve(s), a facepiece, exhalation valve(s) and head harness. Clean air filtered by the cartridges(s) is inhaled from the inhalation valve(s), and exhaled air is exhausted from the exhalation valve(s) to outside atmosphere. It is used in the atmosphere where the concentration of the gases or vapors is less than 0.1 %, and is not used for emergency.

Type

Form

Full-face facepiece

It covers whole face.

Half mask facepiece

It covers only nose and around mouth.

Parts

Tests

Requirements

Head harness and its mounting base of the facepiece

(Pulling Test)
Each combination of head harness and its mounting base of the facepiece is pulled with tension force of 50 Newton for full-face type facepiece, with tension force of 25 Newton for half mask facepiece, and investigated whether breakage or separation is caused.

Breakage or separation on both parts must not be caused.

Breathing tube of front or back mounted type gas mask and its mounting base of the facepiece

(Pulling Test)
Breathing tube and its mounting base of facepiece is pulled by the force of 98 Newton.and investigated whether breakage or separation is caused

Breakage or separation on both parts must not be caused.

Part

Requirements

Gas filter

(Canister and Chemical cartridge

1. Filter material must be packed tightly and not exposed to outside.

2. It must be provided with filter material to capture particulates, if the gas mask has the function to prevent wearer's exposure to particulates.

Inhalation valve

It must work reliably and quickly even for weak breathing.

Exhalation valve

1. It must work reliably and quickly even for weak breathing, at both wet and dry conditions of the valve and the valve seat.

2. When the inside and outside pressures of the gas mask is in equilibrium, the exhalation valve must be kept close tightly, whichever the facepiece is directed to.

3. It must be protected by cover or alike measures so that damage is not caused by forces given from outside.

Head harness

1. It must have appropriate length and elasticity, and the length of harness must be easily adjusted.

Breathing tube

1. It must have appropriate elasticity for expansion and contraction of length, and must cause no inconvenience in airflow when it is bent into variety of forms.

2. It must cause no problem in airflow when it is pressed by chin or arm.

3. The length must be long enough to cause no restriction of head movement.

Test procedures

Requirements

(Test of air tightness)

The air tightness of front or back mounted type gas masks, chin-style gas masks and chemical-cartridge respirators, is tested as follows. First, the exhalation valve(s) and the other end of a breathing tube connecting to the facepiece are closed for a front or back mounted type, or the exhalation valve(s) and the connection port(s) of a facepiece for canister(s) or cartridge(s) are closed respectively by putting a sealing piece(s), and then the facepiece is mounting onto a dummy head of the tightness test equipment. The facepiece is covered with a cloth wetted with an alcohol solution of phenolphthalein. Then, by sending air containing ammonia into the facepiece until the inside pressure reaches at 980 Pascal, color change of the cloth into red is investigated to find the parts where the air tightness is broken on the facepiece.

No leakage shall be detected.

(Test of inhalation resistance)

This test measures the difference between inner and outer pressure of the facepiece putted on a dummy head during passing airflow at the rate of 40 liters per minute in the direction of inhalation. In this test, the canister(s) or cartridge(s) ( involving inhalation valve(s) when the inhalation valves are attached to the canister(s) or cartridges(s)) are removed from the facepiece. When the gas mask has a breathing tube, the pressure difference is measured with the tube bent at 180 degree.

The pressure difference shall not exceed 70 Pascal for front or back mounted type gas masks, and 50 Pascal for chin-style gas masks and chemical cartridge respirators, respectively.

(Test of exhalation resistance)

This test measures the difference between inner and outer pressure of the facepiece putted on a dummy head during passing airflow at the rate of 40 liters per minute in the direction of exhalation. In this test, the air passes for inspiration should be closed.

The exhalation resistance shall not exceed 80 Pascal

(Test of air tightness of exhalation valve at work)

First, the exhalation valve with the valve seat is mounted on an air tightness test equipment, and then the decrease of the inner pressure of the valve is confirmed by drawing the inside air by a drawing pump at the rate of 1 liter per minute. Next, the inner pressure is adjusted at –1,470 Pascal against the atmospheric pressure, then the evacuation of the inner space of the valve is stopped, and then the time for the inner pressure to recover to the atmospheric pressure is measured. The capacity of the inner space of the exhalation valve seat shall be 50 cubic centimeters.

1. The inner pressure must quickly decrease when the inner air is drawn.

2. The time required for the inner pressure to be restored up to normal pressure must be longer than 15 seconds.

(Test of carbon dioxide concentration increase in inspired air)

In the atmosphere of 25 ± 5°C , the facepiece is put on a dummy head with the dimensions described in the following picture, and the connected artificial breathing apparatus is driven at the rate of 15 times a minute and 2.0 ±0.1 liters per stroke (The artificial breathing apparatus supplies exhalation air with 5.0% carbon dioxide.). During this procedure, the carbon dioxide concentration in the inspired air is measured until the concentration reaches a constant concentration. The same procedure is performed with the dummy head without a facepiece.

Dummy Head (in mm)

The difference of carbon dioxide concentrations in the inspired air at the two conditions with and without the facepiece must be lower than 1.0%.

Test procedures

Requirements

(Test of air-tightness)

This test investigates whether leakage is found or not after sending air into the canister or cartridge until the pressure in the canister or cartridge reaches at 1470 Pascal.

No leakage shall be detected.

(Test of inhalation resistance)

This test measures the difference between the pressures of the air flow before and after it passes through a canister or a cartridge at the rate of 40 liters per minute. The canister or cartridge to which an inhalation valve is attached is measured with the valve.

The pressure difference shall not exceed the values described in the Table below, according to the type of the gas mask to which the canister or cartridge is connected and with or without the function of filtration of particulates.

Category

Type of gas mask

Front or back mounted type gas mask

Chin-style gas mask

Chemical-cartridge respirator

For carbon monoxide

With particulate filtration function

S1 &L1

310

-

-

S2 &L2

320

-

-

S3 &L3

400

-

-

Without particulate

filtration function

280

-

-

For gases other than carbon monoxide

With particulate filtration function

S1 &L1

310

280

280

S2 &L2

320

290

290

S3 &L3

400

370

370

Without particulate filtering function

250

220

220

Remark: The value in this Table is in the unit of Pascal.

Test procedures

Requirements

(Test of service life)

Service life is measured, by supplying air containing the gas shown in the right column of the Table below into the canister or the cartridge, at the flow rate of 30 liter per minute, according to the type of the canister or cartridge shown in the left column of the same Table.

During the testing, the temperature and the relative humidity shall be, respectively, 20 °C± 2 °C and 50% ± 5%.

1. The case where a gas analyzer is used;

The air flow containing the test gas at the exit of the gas filter, which has passed through the gas filter, is led into the gas analyzer, and then the concentration of the test gas in the effluent is measured.

2. The case where gas absorption method is applied;

The air flow containing the test gas at the exit of the gas filter, which has passed through the gas filter, is led into the absorbing tube containing absorbing liquid, and then the test gas contained in the test air is absorbed, and the concentration of the test gas is measured.

The time required for the exit gas to reach at the concentration shown in the middle column of the Table below shall be longer than the time shown in the right column of the same Table, according to the kind of canister and cartridge shown in the left column of the same Table.

However, in the case of canister of front or back mounted type gas mask for carbon monoxide which shows an initial leakage of carbon monoxide within 5 minutes from the start of the test, the concentration of the test gas which has passed through the canister shall not exceed 100 ppm within 5 min from the start of the test due to no reaction or no absorption.

Type of gas filter

Test gas

Type of gas filter

Concentration

(ppm)

Time

(min)

Kind

Concentration

Canister of front or back mounted type gas mask for halogens

Chlorine

0.5%

Canister of front or back mounted type gas mask for halogens

1

60

Canister of chin-style gas mask for halogens

Chlorine

0.3%

Canister of chin-style gas mask for halogens

1

15

Cartridge of chemical cartridge respirator for halogens

Chlorine

0.02%

Cartridge of chemical cartridge respirator for halogens

1

40

Canister of front or back mounted type gas mask for organic vapors

Cyclo hexane

0.5%

Canister of front or back mounted type gas mask for organic vapors

5

100

Canister of chin-style gas mask for organic vapors

Cyclo hexane

0.3%

Canister of chin-style gas mask for organic vapors

5

30

Cartridge of chemical cartridge respirator for organic vapors

Cyclo hexane

0.03%

Cartridge of chemical cartridge respirator for organic vapors

5

50

Canister of front or back mounted type gas mask for carbon monoxide

Carbon monoxide

1.0%

Canister of front or back mounted type gas mask for carbon monoxide

5

180

Canister of front or back mounted type gas mask for ammonia

Ammonia

2.0%

Canister of front or back mounted type gas mask for ammonia

50

40

Canister of chin-style gas mask for ammonia

Ammonia

1.0%

Canister of chin-style gas mask for ammonia

50

10

Cartridge of chemical cartridge respirator for ammonia

Ammonia

0.1%

Cartridge of chemical cartridge respirator for ammonia

50

40

Canister of front or back mounted type gas mask for sulfur dioxide

Sulfur dioxide

0.5%

Canister of front or back mounted type gas mask for sulfur dioxide

5

50

Canister of chin-style gas mask for sulfur dioxide

Sulfur dioxide

0.3%

Canister of chin-style gas mask for sulfur dioxide

5

15

Cartridge of chemical cartridge respirator for sulfur dioxide

Sulfur dioxide

0.03%

Cartridge of chemical cartridge respirator for sulfur dioxide

5

35

Remark: The unit ppm in this Table shows one millionth in volume.

(Test of particulate filtering efficiency)

For the gas masks with the function of particulate filtration, the particulate filtering efficiency is measured by the measurements of the particle concentration of the test air flow before and after it passes the canister or cartridge incorporating the particulate filter, and by the succeeding calculation in use of the following equation. The particles used for the test of particulate filtering efficiency is either of the following two kinds chosen depending on the kind of the particulate filter. The particle size distribution of the test particles is represented by the count median diameter.

Particulate filtering efficiency (%) =

Concentration before passing - (mg/cubic meter)	Concentration after passing (mg/cubic meter)	X 100
Concentration before passing (mg/cubic meter)

1. The case where the test particle is sodium chloride;

The concentrations of sodium chloride in the test flow before and after passing through the gas filter are continuously measured with a sodium chloride concentration measuring instrument with the light scattering method. The count median diameter of the particle size of sodium chloride shall be from 0.06 micrometer to 0.10 micrometer and the geometrical standard deviation of the particle size distribution shall be less than 1.8. The air flow containing sodium chloride at the concentration lower than 50 mg per cubic meter with the variation range less than 15% is made pass through the canister or the cartridge at the flow rate of 85 liters per minute until the cumulative sodium chloride supplied to the filter reaches at 100mg. The particulate filtering efficiency is calculated for the maximum concentration of sodium chloride in the air flow downward the canister or the cartridge during the test.

Type

Particulate filtering efficiency (%)

S1

80.0

S2

95.0

S3

99.9

2. The case where the test particle is dioctyl phthalate;

The concentrations of dioctyl phthalate in the test flow before and after passing through the canister or the cartridge are continuously measured with a dioctyl phthalate concentration measuring instrument with the light scattering method. The count median diameter of the particle size of dioctyl phthalate shall be from 0.15 micrometer to 0.25 micrometer and the geometrical standard deviation of the particle size distribution shall be less than 1.6. The air flow containing dioctyl phthalate at the concentration lower than 100 mg per cubic meter with the variation range less than 15% is made pass through the canister or the cartridge at the flow rate of 85 liters per minute until the cumulative dioctyl phthalate supplied to the filter reaches at 200mg. The particulate filtering efficiency is calculated for the maximum concentration of dioctyl phthalate after passing the canister or the cartridge during the test.

2. The case where the test particle is dioctyl phthalate;

The particulate filtering efficiency during the test duration shall be exceeding the value described each in the right column of the Table below, according to the type of the gas filter described in the left column of the same Table.

Type

Particulate filtering efficiency (%)

L1

80.0

L2

95.0

L3

99.9

Type

Color

Gas filter for halogens

Grey and Black (to be shown by two layers)

Gas filter for organic vapors

Black

Gas filter for carbon monoxide

Red

Gas filter for ammonia

Green

Gas filter for sulfur dioxide

Orange

Remark: For gas mask having particulate filtering function, a white line on the side face of the canister or cartridge shall show the location of the filter incorporated within the canister or cartridge.