Respiratory protection

Types of equipment and selection criteria

Filtering devices do not supply oxygen. They may only be used when sufficient oxygen is assured throughout the work, the contaminant is known and its concentration is compatible with the filter capacity and the equipment’s protection factor. INSST selection guidance advises against using filtering devices below 19.5 percent oxygen by volume; reaching that level does not, by itself, mean the atmosphere is safe. For oxygen-deficient, unknown or immediately dangerous to life or health atmospheres, suitable atmosphere-supplying respiratory protection must be selected. Particle filters are classified as P1, P2, and P3 according to increasing efficiency (filtering facepiece respirators as FFP1, FFP2, and FFP3), and gas and vapor filters by type: A for organic gases and vapors with a boiling point above 65 °C; AX for those boiling at or below 65 °C; B for inorganic gases, excluding carbon monoxide; E for sulfur dioxide and other acid gases; K for ammonia and derivatives; SX for specified gases; NO-P3 for nitrogen oxides; and Hg-P3 for mercury. Types A, B, E and K have capacity classes 1, 2 or 3. Manufacturer instructions and restrictions must be observed. This classification contains no general-purpose carbon monoxide filter; filtering escape equipment must not replace suitable protection for work.

Atmosphere-supplying respiratory protection is required when the atmosphere is oxygen-deficient, the contaminant is unknown or lacks adequate warning properties, the concentration exceeds what a filter can handle, or confined-space work or emergencies involve hazardous atmospheres. The suitable air-line or self-contained equipment must be selected for the actual conditions and rescue arrangements. Air-line equipment relies on an external source of breathable air of controlled quality; self-contained breathing apparatus provides limited autonomy, determined by the cylinder’s capacity, and requires specific training.

The selection process begins with a risk assessment: identification of the contaminant and its physical form, estimated or measured concentration, applicable exposure limit, oxygen levels, task duration, physical exertion, environmental conditions, compatibility with other PPE, and user characteristics. The selected protection must reduce exposure below the limit value with a safety margin, using an assigned protection factor justified for the conditions of use. A nominal factor comes from laboratory tests and is not the protection expected at work; INSST recommends using it only to compare equipment types, and facial fit is crucial for equipment that relies on a tight seal against the face; facial hair, glasses, or an incorrect size negate the protection. Appendix 9 of the INSST technical guide on chemical agents and the respiratory protection portal explain selection and fit criteria.

Employer obligations and proper use

• Last measure. Royal Decree 773/1997 requires that PPE be used when risks cannot be avoided or sufficiently limited by technical means of collective protection or by measures, methods or procedures of work organization.
• Documented selection. Analysis and evaluation of risks, definition of the characteristics that the equipment must meet, comparison with the performance of available equipment and selection in accordance with marketing regulations, with consultation with the workers.
• Conformity. Equipment with CE marking in accordance with Regulation (EU) 2016/425 as category III PPE, with declaration of conformity and information leaflet from the manufacturer, and filters compatible with the equipment.
• Fit and testing. Article 5 of Royal Decree 773/1997 requires equipment to suit its wearer. As technical guidance, INSST recommends seal checks before each use and fit testing during initial selection and after relevant changes to facial characteristics.
• Training and information. Theoretical and practical training on risks, equipment limitations, placement, testing, use, maintenance, filter replacement and storage, with practical demonstrations.
• Maintenance and hygiene. Cleaning and disinfection, replacement of filters according to saturation, time or manufacturer’s instructions, inspection of valves and harnesses, protected storage and control of expiration dates; self-contained and air-line equipment require specific maintenance and checks.
• Individual use. The equipment is for personal use unless circumstances require shared use, in which case hygiene and health measures must be adopted.
• Health and fitness monitoring. Consideration of fitness for the use of equipment that involves physiological stress (respiratory resistance, weight, heat stress ), and monitoring of exposed individuals.

Specific situations

• Asbestos and carcinogens. Equipment with a high protection factor in accordance with specific regulations, fit testing, limited usage times and decontamination.
• Silica and dust. Selection depends on the contaminant and residual exposure after engineering controls. For machining quartz agglomerates, INSST NTP 890 specifies FFP3 respirators or P3 filters, including during wet working; protection must be sufficient for actual exposure. FFP2 or P2 must not be assumed suitable for respirable crystalline silica simply because it is a dust.
• Confined spaces. Prior measurement of oxygen and contaminants, forced ventilation and, when the risk persists, air-line or self-contained breathing apparatus, with external monitoring and rescue.
• Biological agents and healthcare. FFP2 or FFP3 filtering facepiece respirators against biological aerosols, distinct from surgical masks, which are medical devices and not PPE.
• Welding and metal fumes. Equipment with particle filters and, where gases are present, combined filters, or motorized equipment integrated into the welding screen.
• Emergencies and fires. Self-contained breathing apparatus for intervention and short-duration escape equipment for evacuating areas with a risk of gases.

Organizational application: how to manage respiratory protection

1. Identify in the risk assessment the tasks and positions with inhalation exposure that could not be sufficiently controlled and define the type of equipment needed for each one.
2. Select equipment using documented criteria (contaminant, concentration, oxygen, protection factor, duration, compatibility, user characteristics) and consult with workers.
3. Perform fit tests for equipment that depends on facial sealing and assign each person their model and size.
4. Train users with practical demonstrations and record the training; train those responsible for supervising use.
5. Establish the maintenance program: cleaning, filter replacement, inspections, storage and expiration dates, with records for each piece of equipment.
6. Monitor actual usage at workstations and correct deviations (use without adjustment, saturated filters, deteriorated equipment).
7. Review the selection in the event of changes in exposure, products, or the results of measurements and health surveillance.

Preventive management software allows you to associate each job and task with the assigned respiratory protection equipment, record deliveries, fit tests and training, plan filter replacements and inspections, and maintain traceability of each piece of equipment.

Limits and common mistakes

1. Using respiratory protection instead of eliminating or reducing exposure with technical and organizational measures.
2. Use filtering equipment in atmospheres with oxygen deficiency, unknown contaminants, or concentrations exceeding the filter’s capacity.
3. Choosing the type or class of filter without identifying the contaminant, or using particle filters instead of gases and vapors.
4. Ignoring facial fit: hair, glasses, unsuitable sizes, or lack of fit testing.
5. Prolonging the use of saturated or expired filters and neglecting cleaning and storage.
6. Delivering the equipment without practical training or supervision of its use.

Royal Decree 773/1997 sets selection, use and maintenance obligations; INSST technical guides on PPE and chemical agents and its respiratory protection portal provide technical criteria. This entry is for information.

Regulatory and reference framework

• Royal Decree 773/1997, of May 30. Use by workers of personal protective equipment: selection, use, maintenance, training and consultation.
• Regulation (EU) 2016/425 on personal protective equipment . Marketing requirements and conformity assessment of PPE, including respiratory protection.
• Royal Decree 374/2001, of April 6. Chemical agents; hierarchy of measures and use of PPE as a last resort.
• Technical guide for the use of personal protective equipment by workers (INSST, 2022) . Criteria for the application of Royal Decree 773/1997.
• NTP 787: Respiratory protection equipment: identification of filters according to their types and classes (INSST) . Types, classes and color code of filters.
• Respiratory protection (INSST) . Thematic portal with selection and use criteria, PPE information sheets, technical standards and documentation.

The UNE-EN standards 149 (self-filtering masks), 140 (half masks), 136 (full-face masks), 143 (particle filters), 14387 (gas and combined filters), 12941 and 12942 (powered equipment) and 137 (self-contained equipment) define the requirements for each type of equipment; Royal Decree 665/1997 and Royal Decree 396/2006 contain specific requirements for carcinogens and asbestos .