Safety Information

Expert Advice for Using Pneumatic Plugs and Gauges.

Working with pipe plugs can be dangerous. Please take it seriously

Working near pneumatic pipe plugs is extremely dangerous and can result in serious bodily injury or even death. According to OSHA standard 1926.21(b)(2), “The employer shall instruct each employee in the recogniti­on and avoidance of unsafe conditi­ons and the regulati­ons applicable to his work environment to control or eliminate any hazards of other exposure to illness or injury.”

Our safety instructions are written as a guide to help train and educate employers and their employees on the safe use of our pneumatic pipe plugs.

Be Aware of and Avoid the Danger Zones
A pipe plug’s danger zone is a funnel-shaped area directly in front of an inflated pipe plug. This danger zone also includes a funnel-shaped area coming out of the manhole where an inflated pipe plug is installed. The entire manhole should also be considered to be in the danger zone, and users should never be in a manhole containing an inflated pipe plug. [INSERT illustration of the danger zone] Users should never inflate a pipe plug while in any of the above described danger zones. We have a complete line of Fill Kit™ retrieval ropes that are designed to allow users to conduct their work safely outside of the above described danger zones.
Determine the Correct Plug Size
Plug Technologies’ pipe plugs are all rated for a specific size pipe or a defined range of pipe sizes. The front of each of our pneumatic plugs has the specified size or usage range clearly marked. Thus, users must always measure the inside diameter of the pipe to be plugged to verify that the plug’s defined usage range includes the pipe size you intend to plug. If the pipe you are trying to plug is shaped irregularly, such as egg-shaped or oval (anything other than round), contact Plug Technologies immediately for additional information regarding safe plugging of irregularly shaped pipes.
Calculate and Monitor Back Pressure
Users must always calculate the amount of back pressure a pipe plug will be subjected to in order to determine the correct plug for a specific application. Back pressure is the amount of air or water (head) pressure that the plug is holding back. This pressure can be behind the plug or in front of the plug. When holding back water, the head pressure can be determined by measuring the amount of water column that is above the plug’s center line. The back cover of our product catalog contains a useful conversion chart.

Example: If a plug is holding a column of water 15 feet high, then the plug would be holding back approximately 6.50 PSI (15 x .4335 = 6.5025 PSI).

When holding back air, back pressure must be monitored using a properly functioning pressure gauge. Users must monitor the back pressure to ensure that it does not exceed the back pressure rating of the pipe plug being used. All our pipe plugs have back pressure ratings molded onto the plug. The back pressure ratings are also included in our product catalog and can be found at our website,

Temperature and Chemical Considerations
The performance of a pneumatic pipe plug can be adversely affected by air temperature and the presence of certain chemicals. Our pipe plugs are manufactured with a high quality natural rubber. Natural rubber plugs are not designed to be used in temperatures exceeding 150⁰ Fahrenheit. Pipe plugs operating in an environment exceeding this temperature rating require an enhanced elastomer. Contact us for your elastomer options. Likewise, natural rubber plugs are not suitable for use in the presence of certain chemicals, which can have a severe adverse effect on the performance of a natural rubber plug. Users must determine what chemicals may come into contact with the pipe plug during the intended application. Always consult a natural rubber compatibility chart or contact PTI to ensure that the pipe plug being used is suitable for the anticipated chemical environment.
Personal Protection Equipment

All users, without exception, must wear personal protection equipment when using Plug Technologies pipe plugs, including, but not limited to: safety glasses, hard hats, hearing protection, and safety boots.

Proper Cleaning of the Pipe
Users must ensure the pipe being plugged is clear of all debris and foreign objects that may reduce the pipe plug’s ability to hold back pressure. Examples of debris and foreign objects typically encountered include, but are not limited to: dirt, rocks, effluent, algae, grease, and chemicals. Any type of material that is trapped between the pipe plug and the wall of the pipe can reduce the plug’s ability to meet the back pressure rating for that pipe plug. Our back pressure ratings are calculated by testing plugs in a clean and dry pipe environment. Pipe conditions other than clean and dry will reduce the published back pressure ratings for our plugs.
Proper Blocking/Bracing of the Pipe
A properly engineered blocking/bracing system must be installed to prevent the pipe plug from moving in the pipe during use. A properly installed blocking/bracing system must also be able to contain both the plug and all material behind the plug in the event of plug failure. Users should always consult with a qualified structural engineer to design the proper blocking/bracing safeguards. Failure to use a properly designed and installed blocking/bracing system could result in serious bodily injury or even death. Users should never use the eyebolts or retrieval ropes as a form of safety devices for the plugs. Eyebolts and the retrieval ropes are designed for lifting and lowering the plugs only and are not rated to tether the full amount of force that a plug can exert.
Proper Placement of the Plug into a Pipe
All pneumatic pipe plugs rely on 100% contact with the pipe wall to achieve proper performance. Thus, pipe plugs must be placed a minimum of one pipe diameter inside of the pipe being plugged.

Example: If you are installing a 12” plug it should be inserted a minimum of 12” inside of the pipe being plugged.

Strict compliance with this minimum plug insertion distance should prevent the pipe plug from protruding outside of the pipe and losing 100% contact with the pipe wall.

Proper Inflation of the Plug
All Plug Technologies pipe plugs have a required inflation pressure molded on the front of the plug. Pipe plugs must always be inflated to the stated inflation pressure. Both over-inflation and under-inflation will adversely affect the performance of the pipe plug and could result in failure of the plug, which could result in serious bodily injury or even death.


Pipe plugs should never be inflated to full inflation pressure unless they are properly installed inside of a pipe. Failure to have a pipe plug contained inside a pipe during inflation could result in serious bodily injury or even death.

Proper Deflation and Removal of the Plug
Prior to deflation of a pipe plug, users must ensure that all built-up pressure behind or in front of the pipe plug has been released. If the pipe plug has been properly blocked/braced to prevent plug movement, then slow deflation of the plug should allow the effluent to be gradually released in a safe manner. The pipe plug should only be removed from the pipe upon full deflation and full release of all pressure and/or effluent.


Deflation of a pipe plug while in one of the danger zones could result in serious bodily injury or even death.

Never Us a Defective Pressure Gauge
A properly functioning pressure gauge is vital to the safe use and operation of a pneumatic pipe plug. Improper handling or storage of a pressure gauge can cause faulty or improper functioning. Thus, pressure gauges should be inspected and tested before each use to ensure proper functioning. Refer to the gauge manufacturer’s operating and maintenance instructions for the proper operation, maintenance, handling and storage of your pressure gauge. Defective pressure gauges should immediately be disposed of and replaced.
Regular Inspection of Plug for Damage
Pipe plugs should be inspected regularly for any conditions that may adversely affect the plug’s overall performance, including the plug’s ability to hold inflation pressure or hold back pressure. Prior to and after any use, users must always inspect the plugs for cracks, punctures, cuts, abrasions, bulges, and corrosion. Never attempt to use a pipe plug that has visible damage or any irregularity.
Proper Storage and Cleaning of a Plug
Store pipe plugs in as close to the original cylindrical shape as possible and out of direct sunlight. Storage of a pneumatic pipe plug in direct sunlight will shorten the life of the plug and could result in premature failure. Plugs can be cleaned using a mild detergent and water.