With the rapid increase in the number of high-rise buildings in cities, the safety hazards and scene limitations of the traditional "spider man" manual hanging rope cleaning mode have become increasingly prominent. The use of drones equipped with intelligent cleaning devices for cleaning has gradually become an important solution in the field of high-rise building cleaning, thanks to its flexible adaptation to irregular buildings and the advantage of reducing the risk of high-altitude operations. At present, the drone cleaning industry is in a transitional stage from technology promotion to large-scale application, and the number of professional service providers continues to grow. However, industry operating norms and service standards have not been fully unified, resulting in frequent legal disputes during contract signing and performance. This article reviews common legal risks in drone cleaning building contracts from a practical perspective and proposes targeted solutions.

1、 Performance disputes and resolution strategies arising from unclear service content and subject matter agreements

In the process of signing a drone cleaning contract, the two parties often have vague agreements on core contents such as "cleaning scope", "quality standards", "equipment and consumables responsibilities", and "operating conditions", which leads to disagreements during the performance stage regarding "whether obligations have been fulfilled" and "who is responsible", and even leads to litigation. The specific dispute scenarios can be divided into three categories:

（1） Common Disputes

1. Unclear definition of cleaning scope and quality standards

Building facade cleaning is not just about "surface cleaning", but involves a dual definition of "spatial scope" and "quality standards". If the contract only provides a general agreement on "cleaning the exterior facade of the building" and does not include "hidden cleaning areas" such as advertising board brackets, waistline carved grooves, etc., the entrusted party may only clean the visible surface, and the principal may refuse to pay the final payment for "missing key parts"; In addition, the subjective expression of "cleanliness meets standards" is extremely strong. The acceptance criteria should be quantified as much as possible in the contract, and the acceptance method should also be clear to avoid a deadlock where the trustee considers it qualified and the client considers it defective.

2. Ambiguous attribution of responsibility for equipment and consumables

Drone cleaning of buildings relies on specialized drone equipment and consumables such as cleaning agents. If the responsibility for the failure and quality commitment of such items are not clearly defined, it will result in additional losses that cannot be recovered. When a drone is damaged due to signal interference, accidental interference from building tenants, or other issues, the trustee may claim that the equipment damage is caused by the operating environment and request the client to share the losses; If the entrusted party uses non neutral cleaning agents that cause the glass coating to peel off or the stone to fade, the entrusting party will find it difficult to recover due to the lack of agreed quality standards for consumables and liability for damages.

3. The homework time and scene restrictions have not been refined

Drone operations are subject to dual restrictions of weather and airspace. If the contract does not specify the "operational conditions" and "responsible parties", it is easy to cause delays in performance. In terms of weather, specific wind force levels and weather conditions should be agreed upon to avoid accidents caused by forced operations by the entrusted party in adverse weather conditions or delays in construction due to frequent weather shutdowns; In terms of airspace, according to Article 19 of the Interim Regulations on the Management of Unmanned Aerial Vehicle Flights, airport clearance zones and flights around government agencies need to be declared in advance. As the party operating the drone, the entrusted party is more familiar with the declaration process, so it should be clearly agreed that airspace declaration is the responsibility of the entrusted party.

（2） Solution ideas

1. Clearly define the cleaning scope and quality standards

The contract shall be accompanied by a building elevation drawing (indicating the hidden cleaning area), and the cleaning standards can be agreed upon in accordance with the high-altitude exterior wall cleaning service specification (SB/T10737-2012). It should also be agreed that "both parties shall be present together during the acceptance, and the written confirmation form shall prevail".

2. Define equipment and consumables responsibilities

Clearly state that the entrusted party shall bear the cost of equipment maintenance and replacement on their own. Consumables must be specified in terms of brand, model, and quality standards, and must be confirmed in writing by the entrusting party before use to avoid building damage caused by consumable issues.

3. Refine homework conditions and responsibilities

It is agreed that "wind force ≤ Level 5, no rainstorm and thunder are operational weather" (can be adjusted according to the actual situation), and the entrusted party shall suspend operation beyond this condition; The airspace declaration is the responsibility of the entrusted party. If the declaration fails and causes delay, the entrusted party shall pay a penalty of 0.5% of the total contract amount per day.

2、 The dilemma of infringement recovery caused by vague division of safety responsibilities and its solution ideas

Unmanned aerial vehicle high-altitude operations involve three risks: third-party safety, construction safety, and operator safety. If the contract does not clearly define the division of responsibilities, once an accident occurs, the commissioning party may be implicated and bear joint and several liability. If both parties shirk responsibility at this time, it will result in extremely high recovery costs. Based on the tort liability section of the Civil Code, the specific dispute scenarios are as follows:

（1） Common difficulties

1. Joint and several liability for third-party damages

Drones falling due to operational errors or equipment malfunctions may result in injuries to pedestrians and damage to vehicles on the ground. If the contract does not specify that the entrusted party is the first person responsible for safety operations, and does not require them to take safety protection measures (such as setting up warning areas or assigning personnel to guide the flow of people), the entrusting party may be identified as jointly infringing due to "selection negligence" and "failure to fulfill supervision obligations", and shall bear joint and several liability for compensation.

2. Difficulty in determining responsibility for damage to building structures

Scratching the curtain wall by drones, infiltration of cleaning agents causing mold growth on the wall, and damage to the insulation layer by high-pressure spraying during homework can easily lead to "responsibility shifting". It is difficult to distinguish whether the damage is caused by aging of the building itself or improper operation. At the same time, there is also controversy over the compensation standards - the trustee claims "compensation based on maintenance costs", while the client demands "compensation based on restoration standards". Scratching the curtain wall may also result in the inability of the building to function properly, causing the client to suffer rent or other additional losses.

3. Dispute over the boundary of responsibility for the safety of entrusted personnel

If the staff of the entrusted party have accidents during the operation, and the contract does not specify the responsibility boundary, the entrusting party may be claimed to have "safety hazards in the provided work site" and shall bear supplementary compensation liability. According to the Work Injury Insurance Regulations, the trustee, as the employer, should have borne the responsibility of work injury insurance, but in practice, additional disputes often arise due to "site liability".

（2） Solution ideas

1. Clarify how to bear responsibility for causing damage to a third party

The contract stipulates that the entrusted party shall set up physical isolation and warning signs in the work area, arrange dedicated personnel to maintain order on site; if the work causes damage to a third party, the entrusted party shall bear full compensation liability, and the entrusting party shall not bear joint liability. At the same time, the entrusted party is required to purchase high-altitude work liability insurance with a coverage of not less than 1 million yuan to cover potential risks.

2. Standardize the identification and compensation of building damage

Both parties shall jointly take photos of the exterior facade of the building for certification before the operation, entrust a professional organization to issue a material testing report, clarify the types of cleaning agents that can be used, and agree that "if the building is damaged due to the operation, the entrusted party shall repair it according to the standard of 'restoring to the pre operation state', and the repair plan shall be confirmed by the entrusting party, and the cost shall be borne by the entrusted party". If the client suffers rent or other additional losses due to scratching the curtain wall, the client has the right to claim compensation from the trustee for such losses.

3. Divide personnel safety responsibility boundaries

The entrusting party shall only provide a work site that is suitable for normal use, and the removal of obstacles and safety protection measures within the site shall be the responsibility of the entrusted party. If the entrusted party's staff are injured at work, the entrusted party shall bear the liability for work-related injury insurance, and the entrusting party shall not be liable for compensation (except for intentional or gross negligence of the entrusting party).

3、 Common disputes and solutions regarding intellectual property ownership and trade secret protection

Drone cleaning involves "technical secrets" (such as drone control systems, cleaning path optimization algorithms) and "data rights" (such as operational images). If the contract does not clearly define ownership and protection clauses, it is easy to cause infringement or leakage disputes, and such disputes result in extremely high costs of rights protection due to the "difficulty in providing evidence".

（1） Common Disputes

1. Leakage and infringement risks of technical secrets

The drone of the entrusted party may carry independently developed core technologies, which belong to the "trade secrets" protected by the Anti Unfair Competition Law (must meet the three requirements of "not known to the public, having commercial value, and taking confidentiality measures"). If the contract does not stipulate confidentiality obligations, the client may obtain technical secrets by requesting technical parameters, dismantling equipment, retaining operation records, and even leaking them to competitors.

2. Disputes over ownership and use of homework images

The building facade images captured during drone operations include detailed structures and equipment layouts, which may involve the client's trade secrets. According to Article 19 of the Copyright Law, if the copyright ownership of a commissioned work is not agreed upon, it shall belong to the commissioned party. However, in practice, the commissioning party often claims that the image should belong to the commissioning party as it is generated to complete the commissioned affairs; At the same time, the trustee may use the images for their own promotion, resulting in damage to the rights and interests of the principal.

（2） Solution ideas

1. Strengthen the protection of technical secrets

The contract clearly states that "the drone control system, algorithms, technical parameters, etc. of the entrusted party are trade secrets, and the entrusting party shall not obtain, copy, use or disclose them; the entrusting party shall not dismantle or test the entrusted party's equipment without authorization; after the completion of the operation, the entrusting party shall delete all information related to the entrusted party's technology", and the confidentiality obligation shall be extended for at least 3 years after the termination of the contract; The agreement states that if the client infringes, they shall compensate the trustee for direct losses (such as research and development costs, project loss losses) and liquidated damages.

2. Clarify the ownership and scope of use of homework images

The copyright of the architectural images captured by unmanned aerial vehicle operations shall belong to the commissioning party; the commissioned party may only use the images for the acceptance and archiving of this cleaning project, and shall not use them for promotion, bidding, or disclosure to third parties; The entrusted party is required to deliver all images to the entrusting party within 15 days after the completion of the assignment, and delete any copies retained by themselves (except for those approved by the entrusting party).

4、 Payment and settlement disputes and resolution strategies

The payment of drone cleaning contracts often leads to disputes due to "unclear payment nodes", "unclear settlement basis", and "missing warranty deposit agreements", especially in scenarios where the acceptance period for high-altitude operations is long and there are special workload calculations. Both parties are prone to disputes over whether the payment terms are met, resulting in the occupation of funds or a setback in performance enthusiasm.

（1） Common Disputes

1. Improper connection between payment nodes and acceptance

If the contract only stipulates "payment of final payment after completion of cleaning" and does not specify the acceptance period and time limit for raising objections, the client may delay the final payment for a long time on the grounds of "incomplete acceptance"; On the contrary, if it is agreed that "50% of the payment will be made in advance before entering the site for work", but the entry time limit and preliminary performance obligations of the entrusted party are not bound, the entrusted party may delay the start of work after receiving the advance payment, resulting in loss of funds occupied by the entrusting party.

2. Disputes over workload accounting and price adjustment

Drone cleaning may lead to price adjustment disputes due to actual pollution levels in the building exceeding the estimated workload in the contract, or the client temporarily increasing the scope of local cleaning. If the accounting standards for workload changes are not agreed upon, the trustee may claim additional fees based on actual working hours, and the principal may refuse to pay with the excuse of "not agreed in advance", resulting in a settlement deadlock.

3. Decoupling the warranty deposit from subsequent maintenance responsibilities

Some contracts do not specify warranty deposit clauses, or the conditions for returning warranty deposit are unrelated to the "cleaning effect maintenance period". If the cleaning agent residue causes the wall to become dirty within a short period of time (such as within 2 months) after cleaning, or if the local dust accumulation is not cleaned due to operational negligence, the client cannot request the entrusted party to rework by temporarily withholding the quality guarantee deposit, and must bear additional cleaning costs.

（2） Solution ideas

1. Link the nodes of installment payment with the acceptance progress

After signing the contract, a 30% advance payment shall be made, 40% shall be paid upon completion of 70% of the cleaned area (subject to the signing of the mid-term acceptance form by the client as the payment condition), 20% shall be paid within 7 days after the overall acceptance is qualified (subject to the signing of the overall acceptance form by the client), and the remaining 10% shall be used as a quality guarantee deposit (with a warranty period of 2 months and no interest refund for any problems caused by cleaning work). At the same time, it is agreed that the client shall organize acceptance within 24 hours after receiving the mid-term acceptance notice, and within 2 hours after receiving the overall acceptance notice. Failure to accept within the deadline shall be deemed as recognition of the cleaning effect.

2. Accounting rules for changes in agreed workload

The contract clearly states that "the degree of building pollution shall be based on the images and inspection reports jointly taken by both parties before the operation. If the actual pollution level exceeds the estimate and leads to an increase in working hours, the commissioned party shall submit a written change application (with working hour accounting basis attached). The commissioning party shall decide whether to confirm within 2 days. After the commissioning party confirms in writing, additional fees shall be added according to the unit price agreed in the contract"; The contract should clearly stipulate that if the cleaning scope is temporarily increased during the cleaning process, the on-site responsible personnel of the commissioning party shall sign and confirm the increased cleaning scope and fee amount to avoid disputes afterwards.

3. Bind the warranty deposit and maintenance responsibility

The starting time of the warranty period shall be calculated from the day after the signing of the overall qualified acceptance certificate by the commissioning party. If there are quality problems such as wall backflow or missing cleaning parts during the warranty period, the commissioned party shall arrive at the site for cleaning within 48 hours after receiving the notice, and the cost shall be borne by the commissioned party. If the commissioned party fails to repair within the time limit, the commissioning party may entrust a third party to repair on its own, and the cost shall be deducted from the warranty deposit. The shortfall may be recovered from the commissioned party

5、 Contract termination and post settlement disputes and resolution strategies

The performance period of the drone cleaning contract may be extended due to factors such as weather, airspace approval, technical failures, etc. If the contract does not specify the "termination situation" and "post termination responsibility", it is easy for one party to unilaterally terminate the contract, which may lead to disputes such as "settlement of the cost of the already performed part", "equipment evacuation loss", "expected benefit compensation", etc. Especially in the scenario where the entrusted party has invested special equipment and the commissioning party has planned the subsequent building use plan, improper post termination handling will lead to the expansion of losses for both parties.

（1） Common Disputes

1. The conditions and procedures for unilateral termination are ambiguous

If the contract does not specify "specific circumstances for unilateral termination", the trustee may claim termination of the contract due to "long-term inability to pass airspace declaration" or "failure of the commissioning party to provide necessary operating conditions (such as temporary power outages causing equipment to be unable to charge)", but cannot prove "force majeure or breach of contract by the other party"; The entrusting party may unilaterally terminate the contract due to the fact that the entrusted party has repeatedly cleaned but still fails to meet the standards, without prior notice, resulting in the idle consumables and equipment prepared by the entrusted party and causing losses.

2. Dispute over settlement of expenses after termination

When the contract is terminated, how to calculate the completed cleaning workload, whether to return the prepaid amount, and how to compensate for the equipment and consumables costs invested by the entrusted party often become the focus of disputes. For example, the trustee has completed 50% of the workload, but the principal refuses to pay the corresponding amount as "not meeting the acceptance criteria"; After the entrusting party prepays 30% of the payment, the entrusted party only enters the site to debug the equipment without actually cleaning it. The entrusting party requests a full refund of the prepayment, and the entrusted party claims to deduct the transportation and debugging costs of the equipment.

3. Unclear division of responsibility for aftermath disposal

After the termination of the contract, is there a clear agreement on the time limit for the evacuation of the entrusted party's unmanned aerial vehicle equipment and remaining consumables, does the entrusting party need to provide evacuation assistance, and who is responsible for the temporary protection of the already operated area? If there is no clear agreement, it may result in storage fees for equipment being stranded on site or additional compensation for damage to the already operated area.

（2） Solution ideas

1. Clarify the circumstances and procedures for unilateral termination

List the situations in the contract that can be unilaterally terminated, such as failure to enter the site for work within 15 days due to reasons not attributable to the entrusted party, such as weather, airspace approval, etc; The principal fails to pay the advance payment as agreed for more than 10 days and still fails to pay after being urged; Force majeure or changes in circumstances such as the prohibition of drone operations due to policy adjustments, or significant changes in building structures that prevent the continued performance of contracts. At the same time, it is agreed that "unilateral termination shall be terminated by sending a written notice to the other party 5 days in advance, stating the reasons and basis for termination, and the contract shall be terminated upon receipt of the notice".

2. Refine the cost settlement rules after termination

After the termination of the contract, both parties shall jointly calculate the completed workload within 3 days and pay the corresponding fees according to the agreed unit price in the contract (refund for overpaid payments and make up for any shortfall); If the specialized equipment already invested by the entrusted party is only used for this project and cannot be reused, the entrusting party shall compensate according to the depreciation value of the equipment (calculated based on the ratio of the contract performance period to the expected total construction period); if the remaining unused consumables are of the designated brand or model by the entrusting party, the entrusting party shall purchase them at the purchase price.

3. Clarify the responsibilities and time limits for handling the aftermath

After the termination of the contract, the entrusted party shall complete the evacuation of equipment and consumables within 5 days, and the entrusting party shall provide necessary assistance such as site access and power connection; If the trustee fails to evacuate on time, they shall pay a daily venue occupancy fee of 500 yuan.

Conclusion

As an emerging industry in high-rise building maintenance, the healthy development of drone cleaning relies on the guarantee of standardized contract management. The parties to the contract should further clarify and agree on common issues in drone cleaning operations, such as service targets, division of safety responsibilities, intellectual property protection, payment and settlement of prices, and handling of post termination or termination matters, based on the general service contract, in order to avoid risks in advance. It is recommended that both parties entrust professional lawyers to participate in the review during the contract drafting stage, and refine the terms based on the actual project scenario. At the same time, industry associations are encouraged to develop unified service standards and contract templates, promote the transformation of the drone cleaning industry towards legal norms, ensure effective protection of the rights and interests of both parties, and achieve sustainable development of the industry.