Translation:Overview of Industrial Testing Outcome of Respiratory Organs Personal Protection Equipment

by Kirillov VF, Filin AS, Chirkin AV

State Budgetary Educational Institution of Higher Professional Education «I.M. Sechenov Moscow State Medical University», 119991 Moscow, RF

Abstract: The article presents information about studies that had been performed to assess the effectiveness of personal respiratory protection (RPD) in the workplace environment for the last 45 years. These data necessitate a revision of fundamental provisions of the respirators selection depending on a known degree of air pollution in the breathing zone.

Key words: respirator, RPD (Respiratory Protective Devices), the Protection Factor, personal sampler, harmful gases and aerosols.

In the workplace, in those cases where it is impossible to apply the technological, technical and sanitary preventive measures (or their low efficiency) [59] for the protection of workers from harmful substances in workplace air in concentrations exceeding the PEL, use RPE. To adequately protect people working in hazardous conditions, requires information on the effectiveness of respiratory protective equipment of various types (designs). In RF, the employer can get it from the state standards (GOST) (which define the quality requirements for certified RPE), directory of manufacturers and publications in the technical literature, in which the coefficients are specified protection respirators different designs.

It is important to emphasize that the choice of appropriate respiratory protective equipment in Russia use protection factors (PF - the ratio of the concentration of contaminants outside the mask of concentration under the mask), obtained from the certification tests in the laboratory. This approach has been generally accepted in the developed countries about 30 years ago. However, the identification of cases of occupational diseases with the correct selection and use of the serviceable respirators, convinced specialists less RPE efficiency in industrial environments with respect to efficiency in the laboratory [15]. This prompted for more research to determine the PF of respirators not only in the laboratory but also in the production environment.

Table 1 presents a brief description of a number of studies carried out to determine the coefficients of protection RPE in the workplace.

Table 1. Brief description of the research that was conducted to determine the protection coefficients of respirators in the workplace

Source1, year of publication	Kind of PF	Harmful substance; (nature and / or place of work); RPD	Number of
			participants	measurements
[29] 1974	E2	Coal dust; mine; 5 half-mask respirators	37	187
[62] 1974	E2	Cotton dust; textile factory; 3 half-mask respirators	5	16
[64 1975	E2	The dust of silicon dioxide; sandblasting; helmet with an air supply5	N6	N6
[50] 1976	W3	Sulfur dioxide; copper smelting; 3 elastomeric half-mask respirators	N6	76
[48] 1979	B4	Carbon monoxide; fire fighting; MSA breathing apparatus	>26	519
[10] 1980	-	Styrene; disposable half-mask respirators	4	16
[66] 1980	E2	Cadmium dust; production of cadmium and paint; half-mask respirators	9	27
[51] 1983	E2	Quartz dust; packing quartz; RPD with an air supply5	4	11
[65] 1983	E2	Lead; smelting of brass; respirator with an air supply5	7	16
[42] 1984	W3	Lead; production of lead; half masks with and without an air supply5	25	50
[21] 1984	W3	Aluminum dust, oxide fluorides; production of aluminum; 3 half-masks	60	75
[52] 1984	W3	Lead; melting and casting of ingots; helmets with an air supply5	12	23
[13] 1984	W3	Mercury; chlorine production, maintenance of equipment, disposable half-mask respirator	7	26
[18] 1984	W3	Aerosol of lead; elastomeric half-mask respirators	11	37
[20]2 1985	W3	Asbestos; removal of insulation from pipes and fire-retardant ceiling; half-mask respirators	17	84
[26] 1986	B4,E2	Lead; hood with air supply and filtering facepice	13	19
[39] 1986	E2	Solvents; different cleaning; 3 elastomeric half-mask respirators	6	23
[55] 1986	W3	Aerosol of lead; production of batteries, helmets with an air supply5	12	47
[20]5 1986	W3	Asbestos; production of brakes; helmet with an air supply5	5	9
[61] 1987	W3	Dust; production of dry mixtures; filtering facepice	7	19
[70] 1987	B4	Organic substances; removal of paint; full facepiece masks	8	47
[20]16 1987	W3	Aluminium, titanium & silicon; grinding and polishing; filtering facepice	3	>9
[20]28 1987	W3	Silicon; shipbuilding; airline respirator with an air supply5	4	15
[7] 1989	PF	Asbestos; removal of insulation; helmet with an air supply5	N6	N6
[20]2А 1989	W3	Lead; smelting of lead; full facepiece masks	13	20
[20]20 1989	W3	Iron and silicon; abrasive machining of castings; airline respirator with an air supply5	N6	39
[69] 1990	W3	Asbestos; stripping; 3 full facepiece masks	~6	~36
[24] 1990	W3	Styrene; manufacture of products made of fiberglass; half-masks	13	63
[20]14 1990	W3	Dust of aluminum; production of aluminum; filtering facepiece	5	23
[20]15 1990	W3	Lead and zinc; cast brass; filtering facepiece	17	62
[20]18 1990	W3	Lead; production of lead; full facepiese respirators with an air supply5	20	55
[20]27 1990	W3	Steroid in pharmaceutical company; helmets with an air supply5	N6	60
[30] 1991	КЗ	Lead chromate, cadmium sulfide; production of dyes; 3 half-masks	11	44
[27] 1992	E2	Dust with radioactive components; half-mask respirators	23	27
[20]1С 1992	W3	Iron, manganese, titanium and zinc; welding and abrasive preparations; shipbuilding; filtering facepieces	N6	32
[23] 1993	W3	Benzo(a)pyrene; 3 elastomeric half-mask respirator and respirator with an air supply5	22	38
[46] 1993	B4, E2	Styrene; shipyard; elastomeric half-mask and supplying air respirators	10	10
[11] 1993	B4	Lead; manufacture of acid batteries; filtering facepiece	85	N6
[71] 1993	W3	Manganese dioxide; manufacture of batteries; filtering facepiece	>12	70
[20]19 1992	W3	Quartz; the dismantling of the oven; airline respirator with an air supply5	4	37
[31] 1993-4	W3	Manufacturing of paints, batteries, flame retardants, smelting of lead; filtering and elastomeric half-mask	30	180
[20]1B 1994	П3	Lead, cutting ships; cadmium dust, paint production; half-masks	36	N6
[67] 1995	E2	Dust, endotoxins; agricultural farms; RPD with and without air supply5	221	N6
[75] 1996	W3	Dust titanium and chromium; painting of aircraft; 3 elastomeric half-masks	22	36
[54] 1996	W3	Zinc and lead; foundry; elastomeric and filtering half masks	26	66
[14] 1996	B4	Lead; removing of old paint; respirators with an air supply5	22	N6
[63] 1998	W3	Asbestos; removal of insulation; respirators with an air supply5	N6	32
[53] 1998	W3	The dust of iron and calcium; steel plant; elastomeric and filtering half masks	17	54
[47] 1999	B4, E2	Styrene; manufacture of ships; respirators with an air supply5	4	N6
[8] 1999	W3	Filling powder fire extinguishers; measured penetration SF6 gas; a full-face mask	15	15
[25] 2000	B4, E2	Styrene; elastomeric half mask	7	N6
[68] 2000	E2	Lead; metallurgical plant; half masks with and without an air supply5	N6	99
[72] 2000	W3	Styrene; shipbuilding; elastomeric half mask	19	46
[28] 2000	E2	Manganese; manufacture of batteries; filtering facepiece	~8	15
[58] 2001	W3	Strontium dust; sanding and primer; respirator with an air supply5	19	37
[20]26 2001	W3	Cadmium; manufacture of Nickel-cadmium batteries; hood with an air supply5	7	33
[73] 2002	E2	Benzo(a)pyrene; coke oven; elastomeric half-mask	9	27
[19] 2002	W3	Welding fumes; shipbuilding; 3 filtering facepieces	14	42
[74] 2003	W3	Dust of compounds of iron; steel plant; 2 elastomeric half-mask	15	55
[9] 2004	W3	Cement dust; manufacture of concrete products; filtering facepiece	15	74
[41] 2005	W3	The dust generated by agricultural harvester; filtering facepiece	1	~30
[40] 2005	W3	Dust, fungi and microbes; agricultural farms; 2 filtering facepieces	21	N6
[32] 2007	W3	Lead; lead production; a full-face mask	18	52
[22] 2007	B4, E2	Xylene and ethylbenzene; painting of ships; elastomeric half-masks	18	49
[35] 2007	W3	Dust of compounds of iron; steel plant; half mask respirator	12	49
[34] 2007	W3	The dust of magnesium and aluminum; machining; filtering half mask	5	53
[33] 2008	W3	Dust strontium and manganese; grinding of an aircraft; respirators with an air supply5	5	~5
[36] 2009	W3	Lead, production of acid batteries; elastomeric half mask respirator	10	45
[38] 2010	W3	Dust; various agricultural works; filtering and elastomeric half-mask	22	N6
[17] 2012	E2	Aerosol of polycyclic aromatic hydrocarbons; coke production; helmet with an air supply5	N6	N6
Effective PF		18 studies	>381 participants	>526 measurements
Workplace PF		45 studies	>569 participants	>1853 measurements
Biomonitoring		9 studies	>193 participants	>644 measurements
Total (1974-2012): 70 available studies; > 1141 participants; > 3061 measurements.

1 – The subscript corresponds to the number of that study, which is described in detail in the review [20]. The list of studies: - the index in the table (page source); authors /source (date).

- 1B (page 34051); C. Coulton, H. Mullins and J. Bidwell / Report at: American Industrial Hygiene Conference and Exposition (AIHCE) (1994).

- 1C (p. 34051); C. Coulton and H. Mullins / Report at conference: AIHCE (1992).

- 2 (p. 34052); T. Nelson and S. Dixon / Report at conference: AIHCE (1985).

- 2A (p. 34058); C. Colton, A. Johnston et al / Report at conference: AIHCE (1989).

- 5 (p. 34062); W. Albrecht, G. Carter et al / Report at conference: AIHCE (1986).

- 14 (p. 34057); C. Colton, A.R. Johnston et al / Report at conference: AIHCE (1990).

- 15 (p. 34057); C. Colton, H. Mullins & C. Rhoe / Report at conference: AIHCE (1990).

- 16 (p. 34058); A. Johnston and H. Mullins / Report at conference: AIHCE (1987).

- 18 (p. 34061); C. Colton and H. Mullins / Report at conference: AIHCE (1990).

- 19 (p. 34066); C. Colton, H. Mullins, & Bidwell / Report at conference: AIHCE (1992).

- 20 (p. 34065); A. Johnston, C. Colton et al / Report at conference: AIHCE (1989).

- 26 (p. 34064); D.V. Collia, et al. / Report at conference: AIHCE (2001).

- 27 (p. 34061); D. Keys, H. Guy and M. Axon / Report at conference: AIHCE (1990).

- 28 (p. 34065); A. Johnston, D. Stokes et al / Report at conference: AIHCE (1987).

2 - E (Effective protection coefficient, effective PF) is the protection factor of the respirator, which is measured in the workplace during the period of work without regard to employee uses a respirator all the time , or does not use a respirator all their working time.

3 - W (protection factor in the workplace, Workplace PF) - protection factor of the respirator, as measured in the workplace only in those periods of time when respiratory protective equipment is used continuously.

4 - B (Biomonitoring) - to determine the effectiveness of respirators experts compare the content of harmful substances or products of their decomposition in the blood, urine, etc people who used respirators and people not exposed to the harmful effects.

5 - a respirator with an air supply under the mask - not negative presure respirator.

6 - N (unknown) - no information

To conduct a systematic scientific measurement and estimation of results was developed related terminology [43-45], formalized in [49]; and carried out statistical processing of results of measurements ([60], etc.).

Measurements of the coefficients of the protection of respirators in the workplace showed that the effectiveness of respirators may be significantly reduced due to the leakage of unfiltered air under the mask through the gaps between it and the face. Gaps can occur because of insufficient proper selection and use of masks and mask slipping during operation.

Table 2 shows the differences in performance requirements to RPD most common types of certification in the laboratory, and the tightening limit the scope of their permitted use (MUC, APF), which occurred due to the discovery of a significant leakage of contaminated air through the gaps during the measurements in the workplace.

Table 2. Comparison of requirements for RPD different designs during their certification and minimum measured PF in the workplace; and the tightening of restrictions permitted area of use that have occurred on the basis of the measurement results of Workplace Protection Factors.

Type of RPD, country	Protection factors		Limit the scope of application
	Requirements for certification, or Nominal PF (2013)	The minimum protection factors of respirators, measured in the workplace	Old limitations (year)	(2013)
Full face mask, USA	≥ 250 0001	11,17 … [69]	≤ 100 PEL (1980)3	≤ 50 PEL4
Full face mask, UK	≥2000 (gas)2 or ≥ 1000 (aerosol)2		≤ 900 PEL (1980) [69]	≤ 40 PEL
A half-mask, USA	≥ 25 0001	2.2, 2.8, 4 …	≤ 10 PEL from 19654,5
Helmet with forced air supply, USA	≥ 250 0001	23, 28 …	≤ 1000 PEL (1992)3	≤ 25 PEL4
Breathing apparatus with air supply on demand, USA	≥ 250 0001	biomonitoring showed low efficiency	≤ 100 PEL (1992)3	≤ 50 PEL4

1. 42 Code of Federal Register Part 84 Respiratory Protective Devices
2. BS EH 136:1998 Full face masks. Requirements, testing, marking.
3. ANSI Z88.2 “Respiratory protection” (1980 and 1992).
4. US Standard 29 CFR 1910.134 ”Respiratory protection”
5. Bureau of Mines “Respirator Approval Schedule 21B” 1965

The studies have shown that the efficiency of the respiratory protective equipment in the workplace depends on : their design; the degree of training workers to use respirators; fit of the mask to the face; the mobility of the employee during operation; microclimatic conditions and other factors. For example, at an elevated temperature due to non-continuous application of high-efficiency respirators effect from their application could be missing (PF = 1.1; 1.2 [73], etc.). The risk of significant and unpredictable reduce the protective properties of common negative pressure respirators prompted to prohibit the use of such respirators (without constant positive pressure under the mask) when levels of air pollutio is, immediately dangerous to life and health IDLH (when short-term exposure can lead to acute poisoning, irreversible damage to the health and/or prevent evacuation, for example - because of the impact on the eye). The values of these concentrations in the RF is not installed, and it hurt to use the conventional methods of selection of respirators.

The results of the few RF studies evaluating the effectiveness of respiratory protective equipment at the workplace, or do not take into account the difference in the leakage of gas and aerosol [1,4], or substantially consistent with the results of foreign studies [2,3,5,6]. But they are not reflected in the sanitary and legislative documents of the RF, and selection of respirators in enterprises is not regulated by the state now.

Conclusions

1. It is necessary to develop selection criteria and requirements for the use of RPD, with the introduction of their substantive provisions in the sanitary legislation.
2. Such criteria should take into account the discrepancy of the declared coefficients of protection actually afforded to workers.
3. The existing RF system of certification of respirators do not provide effective protection of workers.

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