With the improvement of health awareness, electrical stimulation devices such as Tens unit (transcutaneous nerve electrical stimulator) and EMS Massager (electrical muscle simulator) have gradually come into the public view. This type of device stimulates nerves or muscles through microcurrents and is widely used in scenarios such as pain relief, promoting muscle recovery, and body massage. However, while consumers enjoy the convenience of technology, they can't help but have doubts about the safety of the devices. Recently, authoritative institutions and industry experts have provided professional answers to hot issues such as "whether electrical stimulation is safe" and "the critical point of current intensity of four-channel physiotherapy devices".

Authoritative certification: The safety of electrical stimulation equipment is well documented

In fact, the safety of electrical stimulation equipment has long been internationally recognized. Take transcutaneous electrical nerve stimulation (TENS) as an example. Its working principle is to release low-frequency electrical pulses through electrode patches on the skin surface to block the transmission of pain signals to the brain. According to the standards of the International Electrotechnical Commission (IEC), the output current of household TENS devices must be strictly controlled within a safe range, typically not exceeding 0.5mA to 2mA. This value is far below the human body's tolerance threshold for current. Experimental data show that when used properly, the TENS device does not cause damage to nerves or muscles; instead, it can effectively relieve acute or chronic pain.

In addition, the "General Requirements for Basic Safety and Performance of Transcutaneous Acupoint Electrical Stimulation Devices in Traditional Chinese Medicine" (ISO/NP24996), led by the China Academy of Chinese Medical Sciences, has been approved for international project initiation. This standard clearly stipulates the current intensity, frequency range and safety performance of electrical stimulation equipment. This measure not only provides safety guarantees for consumers, but also promotes the international development of electrical stimulation technology.

Four-channel physiotherapy device: How to Define the critical point of current intensity?
For multi-channel physiotherapy equipment (such as four-channel physiotherapy devices), the control of its current intensity is particularly crucial. Take the DLZ-C medium-frequency therapy instrument as an example. This device adopts a four-channel eight-channel design. Under the reference load (500Ω), the maximum output current is 100mA. However, in actual use, the output intensity of the instrument can be adjusted step by step within the range of 0-99 steps, and the increment of each step does not exceed 1mA or 1V. This design ensures that users can flexibly adjust the current intensity according to their tolerance level, avoiding discomfort caused by excessive current.

It is worth noting that the critical point of current intensity of the four-channel physiotherapy device is not a fixed value, but is closely related to the location of use, individual differences and therapeutic purposes. For example, for patients with chronic pain such as periarthritis of the shoulder and tennis elbow, doctors usually recommend starting with a low current intensity and gradually increasing it to the maximum value that the patient can tolerate. For patients with muscle atrophy or nerve damage, electrical stimulation treatment should be carried out under professional guidance to ensure safety and effectiveness.

Technological Breakthrough: Safe Practice of Transcranial direct current stimulation (tDCS)
In addition to TENS and EMS technologies, transcranial direct current stimulation (tDCS), as an emerging neuroregulatory method, has shown broad application prospects in fields such as cognitive ability improvement and depression treatment in recent years. Unlike TMS (Transcranial magnetic stimulation), tDCS releases weak direct current through scalp electrodes and only acts on active neurons, without causing risks such as epilepsy. Research by the National Institutes of Health (NIH) in the United States indicates that under appropriate electrode and conductive paste conditions, A current density not exceeding 25.46A/m² and a duration of less than 20 minutes are both within the safe range.

Domestic clinical trials have further verified the safety of tDCS. Taking the current intensity of 1mA as an example, the simulation experiment shows that the maximum value of its current density is only 0.13A/m², which is only 1/200 of the NIH standard. Furthermore, through magnetic resonance imaging (MRI) observations, it was found that after the subjects received tDCS stimulation for 30 minutes to 1 hour in the safe mode, no abnormal phenomena such as tissue edema or imbalance of the blood-brain barrier occurred in the brain.

Application scenarios: Diversified exploration from body massage to rehabilitation therapy
The application scenarios of electrical stimulation equipment are constantly expanding. In the field of body massage, TENS and EMS technologies have become popular choices for sports recovery and muscle relaxation. For example, when athletes use EMS Massager for muscle activation after training, it can accelerate lactic acid metabolism and alleviate muscle soreness. In rehabilitation treatment, electrical stimulation devices are used for the functional recovery of patients with hemiplegia after stroke, spinal cord injury, etc.

Take spinal cord electrical stimulation therapy (SCS) as an example. This technique implants electrodes on the lateral side of the spinal cord through minimally invasive surgery and uses weak pulses to block pain conduction. Clinical data show that SCS therapy is highly safe and has almost no side effects on the human body. Patients will only feel a slight numbness. This technology offers new treatment options for patients with chronic pain.

Experts suggest: Use electrical stimulation equipment scientifically
Although electrical stimulation devices are relatively safe, experts still suggest that consumers must follow the following principles before using them:

Choose regular products: Give priority to purchasing equipment that has passed international certifications such as ISO and CE, and avoid using "three-no" products.
Read the manual: Thoroughly understand the current intensity, frequency range and contraindications of the equipment. Do not use it beyond the range.
Gradual progress: Start with a low intensity when using it for the first time and gradually increase it to an appropriate level to avoid discomfort caused by excessive current.

Professional guidance: For special groups (such as pregnant women, patients with heart disease, and epilepsy patients), it should be used under the guidance of a doctor.

Future Outlook: A Mutual pursuit of safety and innovation
With the continuous advancement of technology, electrical stimulation equipment is developing in a safer and smarter direction. For example, the new EMS Massager has integrated biometric technology and can automatically adjust the current intensity according to the user's muscle state. The transcutaneous acupoint electrical stimulation device, in combination with the theory of meridians in traditional Chinese medicine, provides personalized treatment plans for patients with chronic pain.

It can be foreseen that under the regulation of authoritative standards, electrical stimulation equipment will play a greater role in fields such as body massage and rehabilitation treatment, safeguarding human health. As long as consumers maintain rational cognition and use it scientifically, they can enjoy the convenience of technology while staying away from safety risks.