PRINTER'S NO. 469
THE GENERAL ASSEMBLY OF PENNSYLVANIA
SENATE BILL
No.
508
Session of
2025
INTRODUCED BY MASTRIANO AND BARTOLOTTA, MARCH 21, 2025
REFERRED TO AGRICULTURE AND RURAL AFFAIRS, MARCH 21, 2025
AN ACT
Prohibiting solar radiation modification or sunlight reflection
methods, cloud seeding and polluting atmospheric
interventions within this Commonwealth; imposing duties on
the Pennsylvania State Police and sheriffs; and imposing
penalties.
The General Assembly of the Commonwealth of Pennsylvania
hereby enacts as follows:
Section 1. Short title.
This act shall be known and may be cited as the Clean Air
Preservation Act.
Section 2. Definitions.
The following words and phrases when used in this act shall
have the meanings given to them in this section unless the
context clearly indicates otherwise:
"Air National Guard." The Pennsylvania Air National Guard, a
reserve component of the United States Air Force.
"Artificial intelligence" or "AI." A field of science and
technology encompassing systems and tools that can perform tasks
typically requiring human intelligence such as learning,
reasoning, pattern recognition and decision making, often
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
through computational techniques like machine learning and
neural networks.
"Cloud seeding." A type of weather engineering or
experimentation that may change the amount or type of
precipitation by dispersing chemicals such as dry ice, silver
iodide or trimethylaluminum into the atmosphere by means of
aircraft or ground generators.
"Entity." Any of the following:
(1) Individual.
(2) Trust.
(3) Firm.
(4) Joint stock company.
(5) Corporation, including a quasi-governmental
corporation.
(6) Nongovernmental organization.
(7) Partnership.
(8) Association.
(9) Syndicate.
(10) Municipality or municipal agency.
(11) Program.
(12) Fire district.
(13) Club.
(14) Nonprofit agency.
(15) Commission.
(16) University, college or academic institution.
(17) Department or agency of this Commonwealth.
(18) The Federal Government or any interstate or
international governance or instrumentality thereof,
including foreign, domestic and mercenary armed services or
region within the United States.
20250SB0508PN0469 - 2 -
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
(19) Artificial intelligence.
"Hazardous." A substance or physical agent by its nature
that is harmful to living organisms generally or to property or
another interest of value.
"Intervention." The act of interfering with weather
processes, altering atmospheric or environmental conditions or
releasing pollutants by methods, including, but not limited to,
solar radiation modification or sunlight reflection methods,
stratospheric aerosol injection, marine cloud brightening,
cirrus cloud thinning, weather modification, cloud seeding or
outdoor pollution dispersion modeling.
"Machine learning." The process in which a machine can learn
on its own without being explicitly programmed.
"Physical agent." An agent, other than a substance,
including, without limitation, RF/MW and other electromagnetic
radiation and fields, barometric pressure, temperature, gravity,
kinetic weaponry, mechanical vibration and sound.
"Pollutant." Any of the following:
(1) An aerosol, biologic, trans-biologic, genetically
modified agent, chaff, metal, radioactive material, acid,
alkali, chemical, chemical compound, contaminant,
microelectronic mechanical system, smart dust, smoke, soot,
substance, fume, vapor or air pollutant regulated by the
Commonwealth.
(2) A mechanical vibration, physical agent, particulate
or waste, including materials that may be recycled,
reconditioned or reclaimed.
(3) A solid, liquid, gaseous or thermal irritant.
(4) An artificially produced electric field, magnetic
field, electromagnetic field, electromagnetic pulse, sound
20250SB0508PN0469 - 3 -
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
wave, sound pollution, light pollution, microwave or ionizing
or nonionizing radiation.
"Polluting atmospheric intervention." An experiment or
intervention involving the release of pollutants, conducted by
any iteration of human, machine learning or artificial
intelligence, or any combination of human, machine learning or
artificial intelligence, that occurs in the atmosphere and may
have harmful consequences upon health, the environment or
agriculture.
"Pollution." The discharge, dispersal, deposition, release,
seepage, migration or escape of pollutants.
"Release." Any activity that results in the issuance of
contaminants such as the emitting, transmitting, discharging or
injecting of one or more nuclear, biological, trans-biological,
chemical or physical agents into the ambient atmosphere, whether
once, intermittently or continuously.
"Sheriff." A Pennsylvania sheriff, the Constitutional
officers responsible for county law enforcement.
"Solar radiation modification" or "sunlight reflection
method." An experiment in the Earth's climatic system involving
the release of pollutants that reduces the amount of sunlight
reaching the Earth's surface. The term includes the use of
interoperable, ground-based, airborne and space-based
facilities.
"Weather engineering." The deliberate manipulation of the
environment for purposes that include changing the weather or
climate by artificial means, typically involving the release of
pollutants into the atmosphere via cloud seeding, for small-
scale, large-scale and global-scale alteration of the
environment.
20250SB0508PN0469 - 4 -
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
"Weather modification." Changing, controlling or interfering
with or attempting to alter, change, control or interfere with
the natural development of cloud forms, precipitation,
barometric pressure, temperature, conductivity or other
electromagnetic or sonic characteristics of the atmosphere.
Section 3. Prohibited activity.
The Pennsylvania State Police or a sheriff shall immediately
issue a cease-and-desist order when cloud seeding or polluting
atmospheric intervention is suspected. The cease-and-desist
order under this section shall have the weight of a court order
and any violation shall be punished in accordance with section
5.
Section 4. Notice to cease Federal or foreign-approved
programs.
(a) Notice.--Government and armed forces projects must meet
all the requirements of this act. If an activity deemed
hazardous by this act has been approved, explicitly or
implicitly, by the Federal Government, the Pennsylvania State
Police or a sheriff shall issue a notice to the appropriate
Federal agency that the activity cannot lawfully be carried out
within or over this Commonwealth.
(b) Implementation.--The Pennsylvania State Police or a
sheriff is authorized to and shall implement this act,
determining whether violations have occurred and, if deemed
necessary, shall refer potentially prohibited activity to the
Air National Guard.
Section 5. Penalties and enforcement.
An entity that engages in a polluting atmospheric
intervention or uses an unmarked or unidentified aircraft or
other vehicle or facility to carry out a weather engineering or
20250SB0508PN0469 - 5 -
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
a polluting atmospheric intervention shall:
(1) Have committed a felony and shall pay a fine of not
less than $500,000 or be imprisoned for not less than two
years, or both.
(2) Be guilty of a separate offense for each day during
which prohibited activity has been conducted, repeated or
continued.
(3) Be deemed in violation and subject to any further
penalties of the act of January 8, 1960 (1959 P.L.2119,
No.787), known as the Air Pollution Control Act.
Section 6. Effective date.
This act shall take effect immediately.
20250SB0508PN0469 - 6 -
1
2
3
4
5
6
7
8
9
10
11
12