El Salvador Imposes Air Quality Monitoring Standards

El Salvador has established permissible limits for atmospheric emissions to protect public health and the environment, specifically targeting air immission concentrations across its national territory, under RTS 13.01.03:26 CALIDAD DEL AIRE AMBIENTAL. INMISIONES ATMOSFÉRICAS. LÍMITES PERMISIBLES

EL SALVADOR – AIR QUALITY

El Salvador Sets National Air Quality Standards

New permissible limits for atmospheric emissions apply nationwide.

22 Jun 2026 Distribution date

What changed

Monitoring mandated for ambient air immission concentrations across the national territory.

Products must comply with ambient air immission limits, including air purifiers and industrial exhaust systems.

Specific exclusions apply to indoor air quality and emissions from mobile or stationary sources.

Who it affects

Suppliers of air control devices must ensure products meet the new ambient air standards.

Key dates

22 Jun 2026 — distribution date; full implementation expected.

El Salvador — ambient air quality standards and monitoring requirements

Compliance Answer: Permissible Limits for Atmospheric Emissions in El Salvador under RTS 13.01.03:26

Direct Answer

El Salvador establishes legally binding permissible limits for atmospheric immission concentrations under Reglamento Técnico Salvadoreño RTS 13.01.03:26: CALIDAD DEL AIRE AMBIENTAL. INMISIONES ATMOSFÉRICAS. LÍMITES PERMISIBLES¹. These limits apply nationwide to protect public health and the environment, targeting seven criteria pollutants: PM₂.₅, PM₁₀, ozone (O₃), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), carbon monoxide (CO), and total suspended particles (PTS). Compliance is enforced by the Ministry of Environment and Natural Resources (MARN)¹.

Regulation Analysis

1. Scope and Applicability

Applies to: Monitoring of atmospheric immission concentrations across El Salvador’s national territory¹.
Exclusions: Indoor air quality, emissions from fixed or mobile sources¹.

2. Permissible Limits for Criteria Pollutants

The regulation sets maximum concentration thresholds for seven pollutants, measured under Normal Conditions of Pressure and Temperature (CNPT: 101.3 kPa, 25°C)¹. Limits are defined for annual averages and short-term periods (e.g., 24-hour, 8-hour, or 1-hour averages), as detailed in Table 1 below:

Pollutant	Unit	Annual Limit (µg/m³)	Short-Term Limit (µg/m³)	Measurement Period
Sulfur dioxide (SO₂)	µg/m³	80¹	365¹	24 hours
Carbon monoxide (CO)	µg/m³	N/A	10,000¹	8 hours
Nitrogen dioxide (NO₂)	µg/m³	100¹	150¹	24 hours
Ozone (O₃)	µg/m³	60¹	120¹	8 hours
Total Suspended Particles (PTS)	µg/m³	75¹	260¹	24 hours
PM₁₀	µg/m³	50¹	150¹	24 hours
PM₂.₅	µg/m³	15¹	65¹	24 hours

Notes:

PM₂.₅ and PM₁₀ are inhalable particulate matter with diameters ≤2.5 µm and ≤10 µm, respectively¹.
PTS includes all suspended particles regardless of size¹.
Conversion formula: To convert ppm to µg/m³ at CNPT, use:

µg/m³ = ppm × Molecular Weight × 40.8714¹.

3. Monitoring and Compliance Requirements

A. Measurement Methodology

Sampling periods: Must account for climatological/seasonal variations, operational cycles of emission sources, and local conditions (e.g., meteorology, topography)¹.
Frequency:
- New projects: Establish a baseline (pre-project conditions) and conduct weekly sampling during construction¹.
- Operational phase: Frequency, location, and sample size determined by MARN-approved monitoring programs¹.
Monitoring locations:
- Gases (e.g., CO, NO₂, O₃): Sampling inlets must be 3–15 m above ground and >10 m from trees¹.
- Particulates (PTS, PM₁₀, PM₂.₅): Sampling inlets 2–15 m above ground and >10 m from trees¹.
- Avoid interference: Sampling sites must be >10 m from unpaved roads, sports fields, or bare lots and not near air conditioning vents, generators, or chemical storage¹.
Separation between samplers:
- PTS/PM₁₀: 2–4 m (gravimetric method)¹.
- PM₂.₅: 1–4 m (gravimetric method)¹.

B. Classification of Monitoring Scales

Monitoring is categorized by coverage radius and purpose (see Table 3):

Classification	Description	Coverage Radius
Personal exposure	Equipment carried by individuals	1–2 m¹
Micro	High-concentration areas near emission sources	2–100 m¹
Median	Specific zones within an area	100–500 m¹
Neighborhood (local)	Conditions within a zone of an area	500 m–4 km¹
Urban	Entire urban area	4–100 km¹

C. Dispersion Modeling

Baseline establishment: New projects must complete a baseline study (including atmospheric dispersion modeling) within 2 years of MARN authorization¹.
Model requirements:
- Use Gaussian dispersion models incorporating annual meteorological variations, topography, emission source characteristics, and wind roses¹.
- Predict high-concentration zones and source influences¹.

D. Conformity Assessment

Authority: MARN (in coordination with other agencies) verifies compliance through annual monitoring plans, denunciations, emergencies, or judicial requests¹.
Laboratories:
- Must use accredited methods for analysis¹.
- Transitional period: Laboratories have 5 years from RTS publication to achieve accreditation; during this period, they must demonstrate technical competence to MARN¹.
Methods: Accepted techniques include automated instrumental methods (e.g., UV photometry for O₃, chemiluminescence for NO₂) and gravimetric methods for particulates¹.

4. Enforcement and Legal Framework

Primary law: Ley de Medio Ambiente (Decree No. 233, 1998) and its amendments¹.
Secondary regulation: Reglamento Especial de Normas Técnicas de Calidad Ambiental (Decree No. 40, 2000)¹.
Penalties: Not specified in RTS 13.01.03:26; refer to Ley de Medio Ambiente for enforcement actions¹.

5. Key Deadlines and Timelines

Requirement	Deadline	Authority	Source
RTS 13.01.03:26 enters into force	6 months after publication in Diario Oficial¹	MARN	¹
New projects: Baseline study completion	2 years from MARN authorization¹	Project owner	¹
Laboratory accreditation	5 years from RTS publication¹	Laboratories	¹

Summary Answer

El Salvador’s RTS 13.01.03:26 establishes nationwide permissible limits for seven atmospheric pollutants (PM₂.₅, PM₁₀, O₃, NO₂, SO₂, CO, PTS) to protect public health and the environment¹. Compliance requires systematic monitoring (with specific sampling heights, locations, and frequencies), dispersion modeling for new projects, and accredited laboratory methods¹. Enforcement is led by MARN, with a 5-year transition period for laboratory accreditation¹. The regulation aligns with Ley de Medio Ambiente and excludes indoor air, fixed sources, and mobile sources¹. For full details, refer to the Diario Oficial publication (August 26, 2003)¹.

Sources

↩ WTO TBT notification 26-03223 — El Salvador https://members.wto.org/crnattachments/2026/TBT/SLV/26_03223_00_s.pdf