Millions of People. Millions of Unanswered Questions.

Across the country, millions are living with allergies, asthma, chronic sinus conditions, and more complex illnesses. Public-health authorities have now acknowledged that damp and water-damaged buildings are associated with a range of adverse health effects, and that biological material can accumulate in indoor dust and become re-aerosolized through normal human activity.

For Many Families, the Search for Answers
Becomes a Journey.

Doctors. Tests. Specialists. Online communities.
Families searching for explanations, sometimes for years,
as they try to understand whether their environment
may be contributing to their health concerns.

They've Had Environmental Assessments. They've Had Structural Repairs.

They've spent tens of thousands of dollars, sometimes more.
The work has been completed. Yet questions remain about the environment in which they live. Their physician may still be concerned about ongoing exposure.

And Now They're Calling You.

“My doctor says I may still be exposed in my home. I've already had environmental assessments and structural repairs. Can you help me?”

In the first 20 seconds, can you demonstrate that you understand their concern?
More importantly, do you have the knowledge to investigate what may still be affecting their environment?

PEPN™ was created to bring people together in the search for answers.

THIS IS WHY PEPN™ WAS CREATED

Connecting People,
Knowledge and a
Higher Standard.

PEPN™ connects environmental professionals, affected occupants, and healthcare providers through more than 40 years of environmental science and over 400 peer-reviewed and clinical publications — advancing a unified, science-aligned approach to understanding, reducing, and verifying environmental exposure.

ENVIRONMENTAL
PROFESSIONALS Expanded knowledge.
Greater capability.
A SHARED PURPOSE Reducing environmental exposure
through science, standards,
and collaboration.
AFFECTED
OCCUPANTS Clearer understanding.
More informed decisions.
HEALTHCARE
PROVIDERS Improved communication.
A common language.
PEPN™  |  Purified Environments Provider Network

Where Environmental
Science Meets Human Health.

PEPN™ is advancing a science-aligned framework for identifying, reducing, and verifying biologically relevant environmental exposure within the built environment.

Find a PEPN Professional › Explore PEPN ›
01
Published
Science
02
Standardized
Assessment
03
Defined
Intervention
04
Objective
Verification
05
Professional
Accountability
Our Mission

Transforming How the Built Environment Is Understood.

To advance environmental health by transforming how the built environment is understood— moving beyond visible conditions and structural correction to identify, measure, reduce, and verify environmental exposure.

Through data, evidence, standards, and controls, PEPN™ is establishing a more accountable standard for the environments in which people live, work, learn, and recover.

Identify • Measure • Reduce • Verify
What Is PEPN?

A New Framework for Environmental Health.

PEPN™ — the Purified Environments Provider Network — is a professional environmental health organization advancing a science-aligned approach to understanding, reducing, and verifying biologically relevant exposures within the built environment.

We connect environmental assessment, intervention, verification, professional education, and accountability into a unified framework focused on one outcome: reducing environmental exposure.
01
Understand Characterize the environment and exposure pathways.
02
Reduce Address sources, reservoirs and exposure pathways.
03
Verify Measure whether environmental conditions improved.
Find Your Path

Environmental Health Connects All of Us.

PEPN brings occupants, healthcare providers, and environmental professionals into a shared framework — while preserving the distinct role of each.

01
For Occupants

I Need Help With My Environment.

If you're concerned about conditions in your home or building, PEPN helps you understand what a comprehensive environmental investigation should consider — and how to find qualified professionals who can help.

Understand environmental testing
Identify potential exposure pathways
Find a PEPN professional
Find Environmental Help ›
02
For Healthcare Providers

I Work With Environmentally Sensitive Patients.

PEPN provides healthcare professionals with a clearer understanding of the environmental investigation process, terminology, measurements, and verification methods used by trained environmental professionals.

Understand environmental findings
Improve clinician–environmental communication
Connect with environmental professionals
Explore Healthcare Resources ›
03
For Environmental Professionals

I Want to Advance My Practice.

PEPN supports environmental professionals who want to move beyond conventional inspection toward a structured, exposure-focused approach grounded in science, defined methods, verification, and professional accountability.

Learn the PEPN-HEART™ framework
Pursue MICRO CEEP™ certification
Join the PEPN professional network
Explore Professional Training ›

PEPN maintains a clear professional boundary: healthcare professionals evaluate and manage patients; environmental professionals investigate and manage buildings. PEPN helps create a common language between the two.

A Building Can Be Remediated. But Was the Exposure Actually Reduced?

Finding a source and correcting damaged building materials are critical steps. But when environmental exposure is the concern, completing the work is not the same as demonstrating that the environment has measurably improved.

The question is no longer only, “Was the source corrected?” It is also, “What changed in the environment?”

Environmental remediation compared with objective post-intervention verification
Correction addresses the source. Verification asks whether measurable environmental conditions improved after intervention.
01
Source Was the underlying environmental source corrected?
02
Reservoirs Were accumulated biological reservoirs addressed?
03
Pathways Were environmental exposure pathways reduced?
04
Verification Do objective measurements show that conditions improved?

Completion and verification answer different questions. Completing remediation documents that corrective work was performed. Environmental verification evaluates whether defined conditions changed following that intervention. Both are important — but they are not interchangeable.

Closing the Loop

This Is Where PEPN-HEART™ Begins.

PEPN-HEART™ connects environmental investigation, characterization, intervention, cleaning, verification, and stabilization into a continuous framework — so the process does not simply end when the work is complete.

Discover PEPN-HEART™ ›
Next   •   The PEPN-HEART™ Framework
The PEPN-HEART™ Framework

Environmental Investigation Should Be a Continuous Process.

PEPN-HEART™ provides a structured framework for moving from environmental investigation through intervention and objective verification — connecting each stage rather than treating them as isolated events.

The goal is not simply to identify a problem. The process continues until environmental conditions can be evaluated after intervention.

01

Assess

Investigate the building, occupant concerns, environmental conditions, moisture, HVAC systems and potential exposure pathways.

›
02

Characterize

Integrate observations, measurements and laboratory information to characterize sources, reservoirs and pathways.

›
03

Intervene

Define corrective actions directed toward identified environmental sources and building conditions.

›
04

Clean

Address environmental reservoirs and residual contamination that may remain after source correction.

›
05

Verify

Reproduce defined measurements where appropriate to determine whether environmental conditions improved following intervention.

›
06

Stabilize

Support building conditions that reduce the likelihood of recurrence and maintain environmental improvements.

↻

Closing the Environmental Loop.

PEPN-HEART™ does not treat assessment, remediation, cleaning and verification as disconnected services. Information from each stage informs the next — and verification provides evidence for determining whether the environmental intervention achieved its intended outcome.

01

Follow the Exposure Pathway

Evaluate how environmental sources and reservoirs may interact with occupied spaces rather than evaluating findings in isolation.

02

Measure What Changes

Where appropriate, repeat defined measurements after intervention so improvement can be evaluated objectively.

03

Document the Outcome

Environmental work should produce a documented record connecting observations, actions and verification.

Explore the PEPN-HEART™ Framework ›
Why the Environment Matters

Behind Every Environmental Problem Is a Human Story.

Buildings are not investigated in isolation. They are the places where people live, work, learn, recover, and spend much of their lives. When environmental concerns arise, people need more than disconnected observations and laboratory results. They need a process that helps make environmental information understandable, actionable, and verifiable.

The building is the environment.
The person is the reason the environment matters.

01

What environmental conditions are present in the building?

02

How could those conditions interact with occupied spaces?

03

Did intervention measurably improve those conditions?

PEPN maintains a clear professional boundary. Healthcare professionals evaluate and manage patients. Environmental professionals investigate and manage buildings. PEPN helps establish a common environmental language that allows those disciplines to communicate more effectively.
Find a PEPN Professional Explore PEPN-HEART™
The Scientific Foundation

Built From Published Science. Organized for the Built Environment.

PEPN-HEART™ draws from decades of published research across environmental health, indoor air quality, building science, microbiology, exposure science, aerosol science, and related disciplines. PEPN brings those bodies of knowledge together within a structured environmental framework.

400+
Peer-Reviewed References

Scientific literature supporting principles incorporated throughout the PEPN framework and educational materials.

40+
Years of Research

Drawing from decades of research across environmental and building-related disciplines.

6
Core Disciplines

Multiple scientific fields brought together to examine the built environment.

From Literature to Practice

Science Does Not Live in a Single Discipline.

Environmental conditions within buildings are influenced by interacting systems: moisture, materials, ventilation, particles, biological reservoirs, occupant activity, and building operation.

Understanding those interactions requires looking beyond a single test result or environmental measurement.

PEPN-HEART™ organizes relevant scientific principles into a repeatable environmental process — from investigation through verification.

Opinions are everywhere. Know the published science.

01

Environmental Health

Understanding environmental conditions and potential routes of human exposure.

02

Building Science

Moisture, materials, pressure, ventilation and building-system interactions.

03

Microbiology

Biological organisms, fragments, reservoirs and environmental indicators.

04

Exposure Science

Examining how environmental agents may move from sources toward occupied environments.

05

05

Aerosol & Particle Science

Understanding airborne particles, transport, filtration and deposition within buildings.

Understanding airborne particles, transport, filtration and deposition within buildings.

06

Indoor Air Quality

Ventilation, filtration, humidity and environmental conditions within occupied spaces.

From Evidence to Environmental Practice
Published Research Peer-reviewed findings across relevant disciplines
→
PEPN-HEART™ Scientific principles organized into a structured framework
→
Environmental Practice Defined investigation, intervention and verification

An important distinction: PEPN-HEART™ is a professional environmental framework developed by PEPN. Individual scientific publications cited by PEPN support specific scientific principles and findings; their inclusion should not be interpreted as an endorsement of PEPN, PEPN-HEART™, or every element of the framework by the authors or institutions of those publications.

Explore the Scientific Foundation ›
One Integrated Environmental System

More Than a Protocol. An Environmental Health Ecosystem.

PEPN connects a science-aligned framework, professional education, certification, research collaboration, and professional governance into an integrated system designed to advance more consistent environmental investigation, intervention, and verification.

01
The Organization

PEPN™

The Purified Environments Provider Network advances environmental health through science-aligned frameworks, professional education, collaboration, and accountability.

Primary Role Framework development, professional education, collaboration, and organizational leadership.
About PEPN ›
›
02
The Framework

PEPN-HEART™

The structured environmental framework connecting investigation, characterization, intervention, cleaning, verification, and stabilization.

Primary Role A repeatable environmental process connecting assessment through post-intervention verification.
Explore PEPN-HEART™ ›
›
03
Professional Certification

MICRO CEEP™

Professional education and certification for environmental practitioners trained in environmental exposure concepts and the PEPN biological exposure system.

Primary Role Professional education, competency development, examination, and certification.
Explore Training ›
›
04
Research & Professional Governance

Governance Research Alliance

The Governance Research Alliance supports the continued development of PEPN through professional collaboration, research review, framework refinement, implementation guidance, and professional accountability.

Primary Role Research review, framework development, professional collaboration, implementation, and accountability.
Explore the Alliance ›
How the Pieces Fit Together

PEPN™ establishes the system. PEPN-HEART™ defines the framework. MICRO CEEP™ develops professional competency. The Governance Research Alliance supports research review, framework development, implementation, and professional accountability.

A Framework Is Only as Strong as Its Implementation.

PEPN is designed to connect published scientific principles with defined environmental methods, professional education, objective verification, ongoing research review, and professional accountability.

Explore PEPN-HEART™ Professional Training
Standards & Verification

Completion Is Not the Same as Verification.

Correcting a source is essential. But when the objective is reducing environmental exposure, the process should also ask whether measurable environmental conditions changed following intervention.

The Verification Principle

Do not simply document that work was completed. Document what changed.

01

Define

Establish the environmental conditions, observations, measurements, and sampling design used to characterize the original environment.

02

Intervene

Correct identified sources, building conditions, reservoirs, and relevant exposure pathways according to the defined scope.

03

Reproduce

Reproduce the original sampling or measurement design sufficiently, where appropriate, to permit meaningful comparison.

04

Compare

Compare post-intervention observations and measurements with the established environmental baseline.

05

Document

Document the findings, limitations, remaining conditions, and whether defined environmental objectives were achieved.

Question One

Was the Work Completed?

Completion documentation addresses whether the defined corrective actions were performed.

✓
Was the identified source corrected?
✓
Were affected materials addressed?
✓
Were defined cleaning actions performed?
✓
Was the corrective scope documented?
Question Two

What Changed in the Environment?

Environmental verification asks a different question: whether defined environmental conditions measurably changed following intervention.

✓
Were relevant measurements repeated?
✓
Were sampling conditions sufficiently comparable?
✓
Did defined environmental indicators improve?
✓
Are remaining conditions and limitations documented?
The PEPN-HEART™ Principle

Post-intervention verification should reproduce the original environmental sampling and measurement design sufficiently, where appropriate, to permit meaningful comparison between pre-intervention and post-intervention conditions.

Environmental verification evaluates environmental conditions and the results of environmental intervention. It does not diagnose medical conditions, determine individual clinical outcomes, or establish that a building caused an occupant's symptoms.

Explore PEPN-HEART™ Find a PEPN Professional
Professional Education & Certification

Learn the Framework. Advance the Practice.

PEPN professional education moves beyond isolated testing and inspection concepts toward a structured understanding of environmental exposure, building systems, intervention, and objective verification.

MICRO Certified Environmental Exposure Professional CEEP Certification
Professional Certification

MICRO Certified Environmental Exposure Professional

MICRO CEEP™ provides a professional certification pathway for environmental practitioners seeking advanced education in environmental exposure concepts and the PEPN biological exposure system.

The training connects building science, environmental investigation, biological exposure concepts, environmental intervention, and verification within a structured professional framework.

PEPN Framework Education
MICRO Certification
CEEP™ Professional Credential
Professional Curriculum

From Environmental Findings to Environmental Understanding.

The curriculum is designed to help environmental professionals understand how individual findings fit within the larger environmental system.

01
Building Systems Moisture, HVAC, ventilation and building interactions.
02
Exposure Pathways Sources, reservoirs, transport and occupied spaces.
03
Environmental Testing Understanding sampling, measurements and limitations.
04
Intervention Connecting findings with environmental corrective action.
05
Verification Evaluating environmental conditions after intervention.
06
Professional Communication Clear environmental reporting across professional disciplines.
Professional Development Pathway
01
Education Complete professional training.
→
02
Examination Demonstrate understanding of course concepts.
→
03
Certification Earn the MICRO CEEP™ credential.
→
04
Professional Practice Apply environmental principles in practice.

Professional scope matters. MICRO CEEP™ education is focused on environmental investigation and environmental exposure concepts. Certification does not authorize medical diagnosis or treatment, nor does it replace professional licenses required by applicable state or local law.

Ready to Advance Your Environmental Practice?

Explore MICRO CEEP™ professional training and learn how PEPN-HEART™ connects environmental investigation, intervention, and verification.

Explore MICRO CEEP™ Training PEPN Professional Network
The PEPN Professional Network

Find Environmental Professionals Who Understand the Framework.

Environmental concerns can become complicated quickly. The PEPN professional network helps connect occupants, healthcare professionals, and other stakeholders with environmental professionals working within a structured, exposure-focused approach.

Connecting People & Professionals

Environmental Questions Need Environmental Expertise.

PEPN brings environmental professionals into a common framework built around investigation, exposure pathways, intervention, verification, and professional communication.

PEPN™
01

Structured Investigation

A broader environmental approach considering building conditions, potential sources, reservoirs, systems, and exposure pathways.

02

Defined Methods

Environmental observations, measurements, and sampling selected within a defined investigative framework.

03

Clear Communication

Environmental findings presented in language occupants and other professionals can more readily understand.

04

Verification Focus

Where appropriate, environmental conditions are reevaluated after intervention to determine what measurably changed.

A Shared Environmental Resource

Who Uses the PEPN Professional Network?

01

Occupants

Homeowners, tenants, and building occupants looking for environmental professionals who can investigate concerns within a structured environmental framework.

02

Healthcare Professionals

Clinicians seeking environmental professionals who can investigate buildings and communicate environmental findings while maintaining clear professional boundaries.

03

Environmental Professionals

Professionals seeking collaboration, referral relationships, education, and connection with others working within the PEPN environmental framework.

PEPN Provider Directory

Start With the Right Environmental Professional.

Use the PEPN provider directory to identify participating environmental professionals and review their listed services, credentials, geographic service areas, and professional information.

PEPN directory participation does not replace professional licensing requirements. Services, qualifications, credentials, licenses, and scope of practice may vary by provider and jurisdiction. Users should independently evaluate whether a professional is appropriately qualified and licensed for the services required.

Find a PEPN Professional Join the Professional Network
Purified Environments Provider Network

Understand the Environment. Change the Outcome.

Better environmental decisions begin with understanding what is happening within the built environment, addressing the conditions that matter, and verifying whether intervention produced measurable change.

01
Understand
02
Reduce
03
Verify
01

I Need Environmental Help.

Connect with environmental professionals who understand building conditions, exposure pathways, environmental investigation, intervention, and verification.

Find a PEPN Professional ›
02

I Want to Understand PEPN-HEART™.

Explore the environmental framework connecting assessment, characterization, intervention, cleaning, verification, and stabilization.

Explore PEPN-HEART™ ›
03

I Am an Environmental Professional.

Advance your understanding of environmental exposure concepts, the PEPN framework, and the MICRO CEEP™ professional certification pathway.

Explore Professional Training ›
The PEPN Standard

Identify what matters. Understand how it moves. Reduce the environmental burden. Verify what changed.

PEPN™ Purified Environments Provider Network