A practical car explosion on a film set, the body lifting in a bloom of fire

The Wolf Safety Series

The Practical
Effects Bible

How fire, water, wind, explosions, blood, and rigging are really done on set, and how to do them without anyone getting hurt.

Explore the effects Watch the reel

Physical FX · Shot in-camera · Safety first

77+Feature credits
35Years on set
11Patents

SFX Department

The Effects

Every physical effect on a film set, broken down by the people who rig them. Pick one and it opens to that chapter below.

01 · Fire

Fire & Pyrotechnics

Controlled flame, fireballs, and the licensing that keeps them safe.

Read the chapter →
02 · Explosions

Blowing Up Cars

How a car body lifts and blooms into fire on a single cue.

Read the chapter →
03 · Water

Rain & Water

Rain towers, tanks, and nozzles that actually read on camera.

Read the chapter →
04 · Air

Wind

Fans sized from a soft breeze to a full storm.

Read the chapter →
05 · Atmos

Fog, Smoke & Cryo

Haze, ground fog, dry ice, and carbon dioxide jets.

Read the chapter →
06 · Injury

Blood & Squibs

Bullet hits, blood, and the look of a wound, built safely.

Read the chapter →
07 · Rigging

Rigging & Load Handling

Slings, shackles, and the math that holds the load.

Read the chapter →
08 · Safety

Safety & Permits

Extinguishers, distances, and the rules that do not bend.

Read the chapter →

Watch · Reel

See it work

Practical effects only make sense in motion. Here is a look at the work on set.

Who made this

The Authors

Three generations of effects work, from the concert stage to the back lot to the next class of technicians.

Steve Wolf at the Special Effects Unlimited shop

Steve Wolf

Special effects · Stunts · Author

Steve Wolf has built physical effects for film and television for more than thirty-five years, with over seventy-seven feature credits and eleven patents in fire suppression and combustion. He coordinates stunts, designs pyrotechnics, and has hosted science programs for Discovery and the History Channel, among them What Destroyed the Hindenburg and Houdini's Last Secrets. He also serves as an expert witness on firearms, pyrotechnics, and on-set safety. He created the Wolf Safety Series to put what the trade knows into plain language.

Stunt & SFX coordination · TV host · Expert witness
stevewolfexpertwitness.com

Tommy Betts teaching at a black powder mortar

Tommy Betts

Pyrotechnics · Fire FX instructor

Tommy Betts runs pyrotechnics for Pink's world tours, where cues fire within feet of the artist and have to land on the beat, every night, safely. He is the lead effects instructor at Stunt Camp, teaching mortars, squibs, and fire stunts to the next class of technicians. For years he presented the Science in the Movies show, both alongside Steve and on his own, turning real on-set effects into live demonstrations for audiences.

Pyrotechnics · Fire FX instructor
IMDb: Roughrider (2012)

Dashton Wolf as a toddler running a snow machine on a foam-covered playgroundOn set at age two

Dashton Wolf

Special effects coordinator

Dashton Wolf grew up on his father's sets and has been around effects work since he was two, the age in this photograph, running a snow machine at full tilt. He made his on-camera debut as a baby in the 2005 short Bending Light and now works as a special effects coordinator in his own right.

Special effects coordinator
IMDb: Bending Light (2005)

Read the full guide

Every chapter, with photographs from the shop and the set and the safety doctrine behind each effect. Read it right here, then take the print and Kindle editions to set.

Start reading The Wolf Safety Series

The Guide

The whole book

Every chapter, photograph, and safety rule, in one place.

Order the gear

Equipment

Every tool and material named in the book, with a direct Amazon order link. Regulated pyrotechnic and high-voltage items are listed but not linked.

As an Amazon Associate, Steve Wolf earns from qualifying purchases.

Atmosphere · Fog, Haze, Smoke

Water-based fog machine

Ground fog, room haze, atmosphere

Amazon ↗

Fog fluid (water-based)

Refill for fog and smoke units

Amazon ↗

Haze machine

Thin even atmosphere to reveal light beams

Amazon ↗

Haze fluid

Refill for hazers

Amazon ↗

Wind

High-velocity drum fan

Storm and strong wind on set

Amazon ↗

High-velocity floor fan

Breeze to moderate wind, hair and wardrobe

Amazon ↗

Rain & Water

Pump-up sprayer (Hudson type)

Small wet-downs and touch-ups

Amazon ↗

Submersible transfer pump

Recirculating water for rain rigs and tanks

Amazon ↗

Brass adjustable hose nozzle

Wet-downs and spray patterns

Amazon ↗

Heavy-duty garden hose

Water supply runs

Amazon ↗

Dust, Dirt & Debris

Fuller's earth

The standard movie dust for haze, puffs, impacts

Amazon ↗

Ground cork granules

Lightweight flying debris that will not injure

Amazon ↗

Peat moss

Drifting dirt and ground cover

Amazon ↗

P100 respirator

Required when powder is in the air

Amazon ↗

N95 dust masks

Light powder protection

Amazon ↗

Blood, Slime & Makeup

Stage blood (Ben Nye)

Film-grade blood for hits and wounds

Amazon ↗

Film blood (Kryolan)

Alternate blood formulation

Amazon ↗

Methyl cellulose

Thickener for blood, slime, and fluids

Amazon ↗

Vegetable glycerin

Blood base, tears, wet-look, fog base

Amazon ↗

Scar wax

Wounds and prosthetic blending

Amazon ↗

Distilled water

Fluid base for blood and fog mixes

Amazon ↗

Molds, Casting & Creature Rigs

Silicone rubber (Smooth-On)

Mold-making and skins

Amazon ↗

Urethane resin (Smooth-On)

Cast rigid and flexible parts

Amazon ↗

Foam latex kit

Creature skins and appliances

Amazon ↗

High-torque RC servo

Drives faces, limbs, and joints

Amazon ↗

Servo brackets and mounts

Mounting servos in an armature

Amazon ↗

RC transmitter and receiver

Radio control for puppeteers

Amazon ↗

Bowden cable and housing

Cable-driven puppet motion

Amazon ↗

Breakaway

Sugar glass / breakaway kit

Safe shatter glass for stunts

Amazon ↗

Breakaway glass mold

Cast bottles and panes

Amazon ↗

Snow & Ice

Biodegradable faux snow

Falling and dressed snow

Amazon ↗

Cotton batting roll

Pre-dressed accumulated snow

Amazon ↗

Gypsum / marble dust

Snow texture and ground dressing

Amazon ↗

Rigging & Load Handling

Galvanized aircraft cable

Wire rope for rigs and pulls

Amazon ↗

Wire rope clips

Cable terminations

Amazon ↗

Copper swage sleeves (NicoPress type)

Pressed cable loops

Amazon ↗

Swaging tool

Press the sleeves

Amazon ↗

Wire rope thimbles

Protect cable eyes

Amazon ↗

Galvanized turnbuckles

Tensioning rigs

Amazon ↗

Screw-pin anchor shackles

Rated connection points

Amazon ↗

Rigging swivels

Prevent cable twist

Amazon ↗

Electric chain hoist

Lifting and flying loads

Amazon ↗

Heavy-duty ratchet straps

Securing loads and rigs

Amazon ↗

Locking carabiners (Petzl)

Rated connectors

Amazon ↗

Descender (Petzl)

Controlled descents

Amazon ↗

Rigging pulleys

Line redirects and mechanical advantage

Amazon ↗

Static rope

Rigging and fall lines

Amazon ↗

Pneumatics & Gas Control

Air pressure regulator

Set and hold working air pressure

Amazon ↗

Pneumatic air cylinder

Drives rams and mechanisms

Amazon ↗

Pneumatic solenoid valve

Fire pneumatic effects on cue

Amazon ↗

Air line and quick connects

Plumb the air system

Amazon ↗

CO2 regulator

Meter carbon dioxide for jets and chilling

Amazon ↗

Nitrogen regulator

Inert pneumatic and cryo work

Amazon ↗

Plumbing · Gas & Water Lines

Black iron pipe and fittings

Gas and high-pressure runs

Amazon ↗

Brass ball valves

Positive shutoff

Amazon ↗

Brass nipples

Short threaded connectors

Amazon ↗

Pipe thread sealant (pipe dope)

Seal threaded joints

Amazon ↗

Liquid-filled pressure gauge

Read system pressure

Amazon ↗

PTFE thread tape

Seal NPT threads

Amazon ↗

Electrical · Effects Power & Wet-Set Safety

GFCI breaker

Ground-fault protection for wet effects

Amazon ↗

Portable GFCI

Inline protection on location

Amazon ↗

Weatherproof electrical box

Outdoor and wet-zone connections

Amazon ↗

Cam-Lok power connectors

High-amperage distribution

Amazon ↗

12-gauge extension cords

Heavy power runs

Amazon ↗

Battery RGB LED tube

Practical effects lighting

Amazon ↗

Fire Safety & Standby

ABC fire extinguisher

General fire watch

Amazon ↗

CO2 fire extinguisher

Electrical and clean-agent standby

Amazon ↗

Welding / fire blanket

Smother and shield

Amazon ↗

Tools & Personal Gear

Cordless screwdriver (Milwaukee)

Everyday build and rig work

Amazon ↗

Lineman's pliers

Wire and cable work

Amazon ↗

Multi-tool (Leatherman)

On-belt everyday carry

Amazon ↗

Leather work gloves

Hand protection

Amazon ↗

Safety glasses

Eye protection, mandatory near effects

Amazon ↗

Ear protection

Around mortars and machinery

Amazon ↗

Flashlight

Set and rig inspection

Amazon ↗

Gaffer tape

Universal set tape

Amazon ↗

MIG welder

Fabricating rigs and mounts

Amazon ↗

Professional Rental or Supply

Specified in the book but stocked by rental houses and specialty suppliers rather than Amazon.

  • Lightning Strikes / Luminys fixtures. Dedicated lightning flash heads. Source: rent or buy through Luminys and lighting rental houses.
  • HMI fixtures and SkyPanels (ARRI). High-output set lighting. Source: grip and lighting rental houses.
  • Ritter aircraft-engine wind fans (Mole-Richardson). Large-scale wind. Source: Mole-Richardson and studio wind departments.
  • High-volume fire pumps (Hale, Darley). Rain-rig water at volume. Source: fire equipment suppliers.
  • Pyrotechnic-grade fog and flame (Le Maitre, Strictly FX). Licensed pyro and flame effects. Source: licensed pyrotechnic houses.

Licensed and regulated · not linked

Restricted pyrotechnic materials and high-voltage hazards. Acquisition and handling belong to a licensed pyrotechnician working under a permit. See Appendix C for the licensing pathway.

  • Squib detonators and electric squibs
  • Firing boxes, arming switches, and deadman pyrotechnic switches
  • High-voltage capacitor banks and lightning arc generators (Tesla coils)
  • Lycopodium powder, magnesium powder, and potassium nitrate
  • Petroleum fuel mixtures for fireballs
  • Black powder, flash powder, lift charges, and detonator cord
  • Cold-spark machines, flame projectors, and pyrotechnic fog cartridges

Firearms Safety at Home

Guns appear in this work every day. The same care that keeps a set safe keeps a home safe: guns and unsupervised children don't mix.

A curious child can find a gun in seconds, and a child can't tell a real firearm from a toy. The fix is the same one used on every professional set: store it so a child can't reach it, can't load it, and can't fire it.

Number 1Firearms are the leading cause of death for children and teens ages 1 to 19 in the United States.
4.6 millionChildren live in a home with a loaded, unlocked gun.
More than halfOf gun owners store at least one firearm unlocked.

Hiding Isn't Securing

A high shelf, a sock drawer, or the top of a closet isn't storage. Children climb, they explore, and they know the hiding spots better than you think. The only thing that stops access is a lock the child can't open.

The Secure Storage Standard

Step 1

Unload

Every firearm, every time. An unloaded gun can't fire by accident.

Step 2

Lock

Store the gun in a safe, lock box, or with a cable or trigger lock. The child can't reach what they can't open.

Step 3

Separate

Keep ammunition locked in a different place from the firearm. Two barriers are better than one.

Choosing a Method

Gun safe

The strongest option. Holds several firearms and resists both children and theft.

Lock box

Fast access for one firearm, with a key or a quick code. Good for a defensive gun you want close.

Cable lock

Threads through the action so the gun can't be loaded or fired. Often free from police departments.

Trigger lock

Blocks the trigger. Use it as a second layer, not as your only lock.

What the Failure Costs

When a child reaches an unsecured gun, the result is measured in seconds and it can't be undone. Secure storage is tied to lower rates of firearm injury and death among young people. It's the single most effective thing a gun owner can do.

From the witness stand

"I've reviewed the cases where a gun was left where a child could reach it. Every one of them was preventable. The lock costs less than the gun, and it's the part that saves a life."

Teach Children What to Do

Storage is the first defense. A child who knows what to do if a gun ever turns up is the second.

Even if you don't own a gun, your kids may encounter one at a friend's house. Every child needs age-appropriate gun safety lessons.
Stop

Freeze the moment you see a gun.

Don't Touch

A gun isn't a toy and isn't yours to handle.

Leave the Area

Walk away from the gun right away.

Tell an Adult

Find a grown-up you trust and tell them.

Common Questions

Doesn't a locked gun defeat the purpose of home defense?

No. A quick-access lock box opens in a second or two with a code or a fingerprint, so the gun stays ready for you and out of reach of a child.

My kids know not to touch guns. Isn't that enough?

Teaching matters, but it isn't a substitute for a lock. Curiosity wins in the moment, and the lesson can't load a gun back into a drawer. Do both.

What if I keep the gun unloaded but not locked?

An unloaded gun is safer than a loaded one, but a child can find ammunition and load it. Lock the firearm and store the ammunition separately.

Where can I get a lock?

Many police departments and sheriff's offices give away cable locks at no cost. Gun safes and lock boxes are sold at any firearms retailer.